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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="us-gaap_ScheduleOfStockByClassTable"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany" xlink:label="dei_EntityEmergingGrowthCompany"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AreaOfLand" xlink:label="us-gaap_AreaOfLand"/>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other research and development costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2021 employee stock purchase plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand And Twenty One Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand And Twenty One Employee Stock Purchase Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2021 Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of license revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of License Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost of License Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumReceivedOnLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Premium Received On License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumReceivedOnLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Premium Received On License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumReceivedOnLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Premium Received On License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Amount [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PurchasesUnderThePurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase Commitment, Remaining Minimum Amount Committed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PurchasesUnderThePurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchases Under the Purchase Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PurchasesUnderThePurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purchases Under the Purchase Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Mature in one year or less</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNoncontrollingInterestPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Noncontrolling Interest Policy Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNoncontrollingInterestPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNoncontrollingInterestPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redeemable Noncontrolling Interest Policy Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Inputs, Level 2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetProductRevenueAndAccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Product Revenue and Accounts Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetProductRevenueAndAccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net Product Revenue and Accounts Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetProductRevenueAndAccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Product Revenue And Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_KY_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Kentucky</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_KY_lbl" xlink:role="http://www.xbrl.org/2003/role/label">KENTUCKY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option Indexed to Issuer's Equity, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value by Liability Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Temporary Equity, Ending Balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Temporary Equity, Beginning Balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares Issued and Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Segmen tReporting Policy Policy TextBlock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents, end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents, beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash equivalents, amortized cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other adjustments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other adjustments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherAdjustmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other adjustments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Shares, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share Purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleReportToBoardFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardOfDirectorsOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board of Directors Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from redeemable convertible preferred stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of Series B redeemable convertible preferred shares, net of issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Redeemable Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeographicBasisCountryOfDomicileMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Country Of Domicile [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeographicBasisCountryOfDomicileMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographic Basis, Country of Domicile [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additions based on tax positions related to current year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccountsReceivableCreditLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Credit Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccountsReceivableCreditLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accounts Receivable, Credit Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccountsReceivableCreditLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, credit losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNonControllingInterestTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of redeemable non-controlling interest.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNonControllingInterestTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Non Controlling Interest [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RedeemableNonControllingInterestTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average grant date fair value of options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneAchievementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Achievement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneAchievementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone Achievement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneAchievementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Achievement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontOfCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Upfront of cash payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontOfCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront of Cash Payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontOfCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">upfront of cash payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontOfCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront of cash payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementRelatedPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement Related Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementRelatedPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License Agreement Related Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementRelatedPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License agreement related payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental stock compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increases recorded to income tax provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Increase in Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwardsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Loss Carryforwards [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwardsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Loss Carryforwards [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateOfUpfrontLicenseFeeReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Of Upfront License Fee Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateOfUpfrontLicenseFeeReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate Of Upfront License Fee Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateOfUpfrontLicenseFeeReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Of Upfront License Fee Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskThirdPartyOversightAndIdentificationProcessesFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents, fair value disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Money market funds, included in cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Valuation allowance as of end of year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Valuation allowance as of beginning of year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Less: valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LeaseForCorporateOfficeFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease For Corporate Office Facility Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LeaseForCorporateOfficeFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease For Corporate Office Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LeaseForCorporateOfficeFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease For Corporate Office Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Federal Statutory Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. federal statutory tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GoingConcernPolicyTextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Going Concern</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GoingConcernPolicyTextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Going Concern [Policy TextBlock]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GoingConcernPolicyTextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Going Concern [Policy TextBlock]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementThirdPartyEngagedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Third Party Engaged [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Documents Incorporated by Reference [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Documents Incorporated by Reference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RoyaltyFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty fee payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RoyaltyFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Fee Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RoyaltyFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty fee payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Percent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share-based Payment Arrangement, Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Jurisdiction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TakedaAssetAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Takeda Asset Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TakedaAssetAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Takeda Asset Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TakedaAssetAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Takeda Asset Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoods_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Finished Goods, Gross</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Inventory</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRepurchaseOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Repurchase of Private Placement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UncertainTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Uncertain Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UncertainTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Uncertain tax positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Cash Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate Cash Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based compensation by share based payment arrangement non vested options granted during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Basic and Diluted Net Loss Per Share Attributable to Common Shareholders/Stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securities Continuous Unrealized Loss Position More Than Twelve Months Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Continuous Unrealized Loss Position More Than Twelve Months Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized losses 12 months or greater fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nontaxable or nondeductible items</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss per share - basic</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InvestmentAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InvestmentAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InvestmentAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of Shares, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of Shares, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Maturities of Our Available-for-Sale Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfMaturitiesForAvailableForSaleSecuritiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Maturities For Available For Sale Securities Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfMaturitiesForAvailableForSaleSecuritiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Maturities For Available For Sale Securities Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfMaturitiesForAvailableForSaleSecuritiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Maturities For Available For Sale Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdditionalMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdditionalMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Milestone Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdditionalMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DotOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">DOT -1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DotOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">DOT One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DotOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">DOT One.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Domestic Tax Jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Percent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Orphan drug credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Orphan drug credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additions based on tax positions related to prior year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_XOMALicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">XOMA License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_XOMALicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">XOMA License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_XOMALicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">XOMA License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred Finance Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Finance Issuance Costs policy.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Finance Issuance Costs policy text block [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Finance Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Retained Earnings (Accumulated Deficit), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Retained Earnings (Accumulated Deficit), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Retained Earnings (Accumulated Deficit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-Based Compensation Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefitsPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Changes in Unrecognized Tax Benefits, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefitsPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Changes in Unrecognized Tax Benefits, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefitsPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in unrecognized tax benefits, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Well-known Seasoned Issuer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Well-known Seasoned Issuer</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeiture</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase Price Per Share</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MerckLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Merck License Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MerckLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Merck License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MerckLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Merck License Agreement [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SummaryOfPerformanceStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of Performance Stock Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Milestone Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Milestone Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued milestone liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseContractualTermAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Contractual Term [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseContractualTermAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Class A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Class A</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee Lease Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. federal statutory tax rate, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securitie Continuous Unrealized Loss Position Less Than Twelve Months Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securitie Continuous Unrealized Loss Position Less Than Twelve Months Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized Losses Less Than 12 Months, Fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research And Development Agreements Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts Receivable, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_NC_lbl" xlink:role="http://www.xbrl.org/2003/role/label">NORTH CAROLINA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_NC_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">North Carolina</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskRoleOfManagementTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Role of Management [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnamortizedStockBasedCompensationForStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unamortized stock-based compensation for stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnamortizedStockBasedCompensationForStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unamortized stock-based compensation for stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnamortizedStockBasedCompensationForStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unamortized stock-based compensation for stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityRelatedTrancheLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity Related Tranche Liability [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityRelatedTrancheLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary Equity Related Tranche Liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityRelatedTrancheLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Related Tranche Liability [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Paid, by Individual Jurisdiction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NasdaqStockMarketMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nasdaq Stock Market [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NasdaqStockMarketMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nasdaq Stock Market [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NasdaqStockMarketMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nasdaq Stock Market</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Fair Value of The Incentive Shares Estimated Using An Option Pricing Model</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unvested common shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unvested common shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unvested Common Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested common shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyAccrualAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Loss Contingency Accrual, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyAccrualAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Loss Contingency Accrual, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyAccrualAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency Accrual</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyAccrualAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Termination and cancellation charges payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyAccrualAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Litigation amount awarded from other party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskMateriallyAffectedOrReasonablyLikelyToMateriallyAffectRegistrantFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashEquivalentsUnrealizedGains_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash equivalents, unrealized gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashEquivalentsUnrealizedGains_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Equivalents, Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashEquivalentsUnrealizedGains_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash Equivalents Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteRedeemablePreferredStockIssuePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteRedeemablePreferredStockIssuePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note, Redeemable Preferred Stock, Issue, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsStateTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsStateTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, State Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SamuelBlackmanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Samuel Blackman [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SamuelBlackmanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Samuel Blackman [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SamuelBlackmanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Samuel Blackman [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardCommitteeOrSubcommitteeResponsibleForOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonSharesPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Shares Purchase Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonSharesPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Shares Purchase Agreement [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ViractaLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Viracta License Agreement Member</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation, State and Local Income Tax, Amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Address, State or Province</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested restricted stock units at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unvested restricted stock units at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Unvested restricted stock units at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Series B redeemable convertible preferred shares for cash, net of issuance costs of $243, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Noncontrolling Interest [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock, capital shares purchase an additional for future issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterials_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Raw Materials, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterials_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Raw materials</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State and local income taxes, net of federal income tax effect, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">License revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Share-based Compensation Expense Recorded in The Accompanying Condensed Consolidated Statements of Operations and Comprehensive Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other adjustments, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securitie Continuous Unrealized Loss Position Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securitie Continuous Unrealized Loss Position Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon exercise of stock options, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Tax Assets and Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Deferred Tax Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Third-PartyCROCMOAndOtherThird-PartyClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Third-Party CRO, CMO and Other Third-Party Clinical Trial Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Third-PartyCROCMOAndOtherThird-PartyClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Third-Party CRO, CMO and Other Third-Party Clinical Trial Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Third-PartyCROCMOAndOtherThird-PartyClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Third-party CRO, CMO and other third-party clinical trial costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConcentrationOfCreditRiskAndOtherRisksAndUncertaintiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration of Credit Risk and Other Risks and Uncertainties [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConcentrationOfCreditRiskAndOtherRisksAndUncertaintiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Concentration of Credit Risk and Other Risks and Uncertainties [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConcentrationOfCreditRiskAndOtherRisksAndUncertaintiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration Of Credit Risk And Other Risks And Uncertainties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Research and Development Expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred revenue, current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue, Current</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Credit Carryforwards, Research</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalized R&amp;D Section 174 Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OptionRepricingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option Repricing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OptionRepricingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Option Repricing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OptionRepricingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Option Repricing</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwardsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Loss Carryforwards [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ExternalCostsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External costs:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ExternalCostsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">External Costs [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashEquivalentsUnrealizedLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash Equivalents Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestEquityPreferredCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Carrying value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestEquityPreferredCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestEquityPreferredCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable convertible preferred shares, no par value; no shares authorized, issued and outstanding at December 31, 2021; 22,851,257 shares authorized, issued and outstanding at December 31, 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Recognition, Milestone Method, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payment received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesIssuedAsAResultOfConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common stock shares issued as a result of conversion of temporary equity into permanent equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesIssuedAsAResultOfConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Shares Issued As A Result Of Conversion Of Temporary Equity Into Permanent Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesIssuedAsAResultOfConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock Shares Issued As A Result Of Conversion Of Temporary Equity Into Permanent Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Grant date fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted Average Grant Date Fair Value, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementMilestonePaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement Milestone Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementMilestonePaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License Agreement Milestone Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementMilestonePaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License agreement milestone payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization Of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Class B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Class B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Inputs, Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand and twenty one stock incentive plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">2021 Stock Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyOneStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand And Twenty One Stock Incentive Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of fair value, assets and liabilities measured on recurring basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product revenue, net [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IpsenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ipsen License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IpsenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Ipsen License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IpsenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ipsen License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_VolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Volume Weighted Average Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_VolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Volume Weighted Average Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_VolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Volume weighted average price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SprintBioscienceAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sprint Bioscience Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SprintBioscienceAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sprint Bioscience Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SprintBioscienceAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sprint Bioscience Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net operating loss carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidByIndividualJurisdictionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Paid, by Individual Jurisdiction [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 8)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Leases [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CentralAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Central America [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CentralAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Central America</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted Average Grant Date Fair Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average Grant Date Fair Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested restricted stock units at December 31, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unvested restricted stock units at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcess_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Work in Process, Gross</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Present value of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating Lease, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquitySharesConvertedIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity shares converted into permanent equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquitySharesConvertedIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Shares Converted Into Permanent Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquitySharesConvertedIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary equity shares converted into permanent equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorFirmId_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Firm ID</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherIndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Individual Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherIndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Individual Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherIndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other Individual Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ObligationsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Obligations [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ObligationsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee Lease Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in valuation allowance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseContractualTermDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Contractual Term [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseContractualTermDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOtherLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross state NOL</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrepaidExpensesAndOtherCurrentAssetTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses and Other Current Asset [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Effective Income Tax Rate Reconciliation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty One Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty One Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyOneEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand Twenty One Employee Stock Purchase Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskProcessForInformingManagementOrCommitteesResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Private Placement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepositContractsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deposit Contracts, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Tax Credit, Percent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedFederalAndStatePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued federal and state payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedFederalAndStatePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued federal and state payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedFederalAndStatePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued federal and state payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in deferred tax assets valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Changes in valuation allowances, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Common Stock Shares Reserved For Future Issuance Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Common Stock Shares Reserved For Future Issuance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Common Stock Shares Reserved for Future Issuance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_WeightedAveragePriceOfCompanysCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted Average Price of Company's common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_WeightedAveragePriceOfCompanysCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Price of Company's common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestByLegalEntityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Noncontrolling Interest [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of Product Revenue</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CVRAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">CVR Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CVRAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">CVR Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CVRAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CVR Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of Estimates</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Share based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EffectiveIncomeTaxRateShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Share based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Nonvested Share Activity</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront payment.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront payment</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentsNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone payments not yet paid</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementWithIpsenPharmaSasMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement with Ipsen Pharma SAS [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LicenseAgreementWithIpsenPharmaSasMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License agreement with Ipsen Pharma SAS [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securitie Continuous Unrealized Loss Position Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securitie Continuous Unrealized Loss Position Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskMateriallyAffectedOrReasonablyLikelyToMateriallyAffectRegistrantTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Reclassifications_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reclassifications</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Reclassifications_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassifications [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expected to vest at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current State and Local Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Credit Carryforward, Expiration Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">State and local</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementExpertiseOfManagementResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Expertise of Management Responsible [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Pre-funded warrants purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Tax Jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Indefinite-Lived Intangible Assets (Excluding Goodwill), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Indefinite-Lived Intangible Assets (Excluding Goodwill), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Indefinite-Lived Intangible Assets (Excluding Goodwill), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TemporaryEquityTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary Equity [Text Block].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Details Domain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Details [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Details</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedRoyaltiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Royalties, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedRoyaltiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued royalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Permanent items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Permanent differences</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockOptionExercisePriceDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Option Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockOptionExercisePriceDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Option, Exercise Price, Decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Inventory, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible asset basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Goodwill and Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfProductRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Product Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfProductRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost of Product Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfProductRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of product revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Excersise price of pre-funded warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercise price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CharlesYorkMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Charles York [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CharlesYorkMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Charles York [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CharlesYorkMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Charles York [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_IcfrAuditorAttestationFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ICFR Auditor Attestation Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_IcfrAuditorAttestationFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ICFR Auditor Attestation Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Individual Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Individual Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IndividualCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Individual Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_BalanceSheetItemsLinesItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Balance Sheet Items [Lines items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_BalanceSheetItemsLinesItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Balance Sheet Items Lines items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Restricted Stock Units (RSUs)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Redeemable convertible preferred shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">In Process Research and Development, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Details Axis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Details [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DetailsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Details</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Total current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnrecognizedTaxBenefitsMoreLikelyThanNotThresholdPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits More Likely Than NotThreshold Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnrecognizedTaxBenefitsMoreLikelyThanNotThresholdPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unrecognized Tax Benefits More Likely Than NotThreshold Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnrecognizedTaxBenefitsMoreLikelyThanNotThresholdPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized Tax Benefits More Likely Than Not Threshold Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TenantImprovements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tenant Improvements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TenantImprovements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tenant improvement allowances receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instruments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) Attributable to Parent, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Marketable securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalSharesReservedForFutureIssuanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Incremental Shares Reserved For Future Issuance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalSharesReservedForFutureIssuanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Shares Reserved For Future Issuance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalSharesReservedForFutureIssuanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental Shares Reserved For Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_NY_lbl" xlink:role="http://www.xbrl.org/2003/role/label">NEW YORK</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_NY_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New York</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfStockOptionsAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock Options Assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfStockOptionsAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Stock Options Assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfStockOptionsAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Stock Options Assumptions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfStockOptionsAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Stock Options Assumptions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finite-Lived Intangible Assets, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_IL_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Illinois</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="stpr_IL_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ILLINOIS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Issued During Period, Shares, Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Common Shares Used In Computing Net Loss Per Share, Basic And Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of common shares used in computing net loss per share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average shares outstanding - diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cover</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdjustmentToAdditionalPaidInCapitalLossOnConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustment to additional paid in capital loss on conversion of temporary equity into permanent equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdjustmentToAdditionalPaidInCapitalLossOnConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment To Additional Paid In Capital Loss On Conversion Of Temporary Equity Into Permanent Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AdjustmentToAdditionalPaidInCapitalLossOnConversionOfTemporaryEquityIntoPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustment to additional paid in capital loss on conversion of temporary equity into permanent equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RecentAccountingGuidanceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Recent Accounting Guidance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RecentAccountingGuidanceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Recent Accounting Guidance [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_RecentAccountingGuidanceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Guidance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Conversion of incentive shares</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRVRelatedObligationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PRV Related Obligation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRVRelatedObligationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PRV Related Obligation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRVRelatedObligationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PRV Related Obligation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Percentage of Outstanding Stock Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance Sheet Items</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeGainLossOnDerivativeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative, Gain (Loss) on Derivative, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeGainLossOnDerivativeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative, Gain (Loss) on Derivative, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SharesCommittedUnderESPPMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares committed under ESPP</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Benchmark [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Treasury Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">US Treasury Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Cash Equivalents, Marketable Securities, and Unrealized Gains and Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of operating segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, general and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainOnSaleOfInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain on Sale of Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainOnSaleOfInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain from sale of priority review voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainOnSaleOfInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain from sale of priority review voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liquidation Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Liquidation Preference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation arrangement by share-based payment award, options, vested, number of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Vested and expected to vest at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Commitment, Remaining Minimum Amount Committed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase Commitment, Remaining Minimum Amount Committed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Finite-Lived Intangible Assets, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Finite-Lived Intangible Assets, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unamortized finite-lived intangible asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total future expected amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental stock compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan (ESOP), Compensation Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LessorLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LessorLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessor, Leases [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UndeliveredRelapsedOrRefractoryFront-LineAndCompanionDiagnosticResearchAndDevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Undelivered Relapsed or Refractory, Front-Line and Companion Diagnostic Research and Development Services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UndeliveredRelapsedOrRefractoryFront-LineAndCompanionDiagnosticResearchAndDevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Undelivered Relapsed or Refractory, Front-Line and Companion Diagnostic Research and Development Services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UndeliveredRelapsedOrRefractoryFront-LineAndCompanionDiagnosticResearchAndDevelopmentServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Undelivered Relapsed or Refractory, Front-Line and Companion Diagnostic Research and Development Services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recently Issued Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Future Lease Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Series B redeemable convertible preferred shares for cash, net of issuance costs of $243, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of redeemable convertible preferred shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other adjustments, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OwnershipAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ownership [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Term of Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation arrangement by share-based payment award, fair value assumptions, expected dividend payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share-based compensation arrangement by share-based payment award, fair value assumptions, expected dividend payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current portion of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less : current portion of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Less: current portion of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Short-Term Investments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research And Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total research and development expenses</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SalesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales agreement member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SalesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SalesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ClassOfStockSubDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class Of Stock Sub.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ClassOfStockSubDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock Sub [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ClassOfStockSubDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class Of Stock Sub</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentFederalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock issued in IPO, net of issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrepaidResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrepaidResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid Research and Development Expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrepaidResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrepaidResearchAndDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">One Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">One Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OneCustomerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">One Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total intrinsic value of the options outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Outstanding at March 31, 2022, Aggregate Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Outstanding at December 31, 2025, Aggregiate Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsByJurisdictionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit), Continuing Operations, by Jurisdiction [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsByJurisdictionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashConsiderationPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Aggregate cash consideration paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashConsiderationPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate Cash Consideration Paid.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashConsiderationPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate cash consideration paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AggregateCashConsiderationPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate cash consideration paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GrossProceedsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Proceeds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GrossProceedsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Gross Proceeds.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_GrossProceedsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gross Proceeds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected dividend yield</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based compensation by share based payment award fair value assumptions dividend yield</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and expected to vest at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneCashPaymentReceivedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone, Cash Payment Received, Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneCashPaymentReceivedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone, Cash Payment Received, Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestoneCashPaymentReceivedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone, cash payment received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk free rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Risk-free interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FrontlinePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Frontline Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FrontlinePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Frontline Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FrontlinePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Frontline Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Conversion, Converted Instrument, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseCommitmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase Commitment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseCommitmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Commitment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndRetirementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Benefits [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement Domain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental compensation cost related to vested stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Income taxes paid (net of refunds)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Productive Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Proceeds from Sale of Productive Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of priority review voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from sale of priority review voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFederalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFederalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Federal Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfUnvestedRestrictedStockUnitsRollForwardTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Unvested Restricted Stock Units Roll Forward [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfUnvestedRestrictedStockUnitsRollForwardTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of The Unvested Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfUnvestedRestrictedStockUnitsRollForwardTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Summary of Restricted Stock Units Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetOperatingLossCarrybackPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Operating Loss, Carryback period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetOperatingLossCarrybackPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net Operating Loss, Carryback period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NetOperatingLossCarrybackPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Operating Loss Carryback Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrvPressureReliefValveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PRV (Pressure relief valve) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PrvPressureReliefValveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PRV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Attributable to Redeemable Noncontrolling Interest, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Redeemable Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToRedeemableNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss attributable to redeemable convertible noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentRiskAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instrument [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConditionsForIssueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditions For Issue Domain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConditionsForIssueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditions For Issue [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ConditionsForIssueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conditions For Issue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfObligationsToRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Obligations To Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfObligationsToRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment Of Obligations To Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfObligationsToRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of Obligations to Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NoncurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">NonCurrent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NoncurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">NonCurrent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_NoncurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedPayrollRelatedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Payroll Related Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedPayrollRelatedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Payroll Related Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedPayrollRelatedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued payroll related expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration risk percentage of net product revenue and accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DisclosureDetailsOfActivitiesRelatingToIncentiveSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure details of activities relating to incentive shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DisclosureDetailsOfActivitiesRelatingToIncentiveSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Details Of Activities Relating To Incentive Shares [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DisclosureDetailsOfActivitiesRelatingToIncentiveSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of The Incentive Shares Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Revenues, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Royalty Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">InvestmentIncomeNet</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Investment Income, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PatentCostsPolicytextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Patent Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PatentCostsPolicytextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Patent Costs [PolicyTextBlock]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PatentCostsPolicytextblock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Patent Costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment, after Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment, after Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Unrealized (loss) gain on available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unrealized gain on available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrealized loss on available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized (loss) gain on available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_JeremyBenderMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Jeremy Bender [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_JeremyBenderMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Jeremy Bender [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_JeremyBenderMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Jeremy Bender [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyTwoEquityInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand And Twenty Two Equity Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyTwoEquityInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand And Twenty Two Equity Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyTwoEquityInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2022 Equity Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandAndTwentyTwoEquityInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 Equity Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted Average Exercise Price, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average Exercise Price, Begining Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationArrangementByShare-BasedPaymentAwardOptionsUnvestedInPeriodFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Unvested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationArrangementByShare-BasedPaymentAwardOptionsUnvestedInPeriodFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Unvested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationArrangementByShare-BasedPaymentAwardOptionsUnvestedInPeriodFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental compensation cost related to unvested stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end of year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of year</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfPrepaidAndOtherCurrentAssetstableTextBlockTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Prepaid And Other Current Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfPrepaidAndOtherCurrentAssetstableTextBlockTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Prepaid Expenses and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unvested Common Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unvested Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UnvestedCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedRebates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Rebates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedRebates_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Rebates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AccruedRebates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued rebates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash Payment Against Milestone Achievement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Payment Against Milestone Achievement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash payment against milestone achievement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Finite-Lived [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfChangesInTheValuationAllowanceForDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Changes in the Valuation Allowance for Deferred Tax Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfChangesInTheValuationAllowanceForDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Changes in the Valuation Allowance for Deferred Tax Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ScheduleOfChangesInTheValuationAllowanceForDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Changes in the Valuation Allowance for Deferred Tax Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized cost, Mature in one year or less</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievementPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash payment against milestone achievement, per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievementPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Payment Against Milestone Achievement, Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CashPaymentAgainstMilestoneAchievementPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash Payment Against Milestone Achievement, Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series A Redeemable Convertible Preferred Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Expected term (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Time to liquidity (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Recurring</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Accrued Liabilities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total future minimum lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total future minimum lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: Imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Research and development tax credit, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development tax credit, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TakedaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Takeda [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TakedaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Takeda.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series B Redeemable Convertible Preferred Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Components</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance Stock Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Stock Units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance Stock Units Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenuePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of License Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenuePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of License Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CostOfLicenseRevenuePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost of License Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total non-operating income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalTaxJurisdictionOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalTaxJurisdictionOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">State and Local Tax Jurisdiction, Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Revenue, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term portion of deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred revenue, noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InternalCostsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Internal Costs [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InternalCostsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Internal Costs [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_InternalCostsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Internal costs:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Payment of Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of Milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment of Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less accumulated amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Receivables, Net, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common Stock Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, $0.001 par value; 500,000,000 shares authorized as of December 31, 2025 and December 31, 2024; 102,982,700 and 101,116,162 shares issued and outstanding as of December 31, 2025 and December 31, 2024, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FoundationMedicineIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foundation Medicine</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FoundationMedicineIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foundation Medicine, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_FoundationMedicineIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Foundation Medicine, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesForAssessingIdentifyingAndManagingThreatsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of Long-Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Amortization Expense For Amortizable Finite-Lived Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityPublicFloat_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Public Float</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityPublicFloat_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Public Float</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Expected volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securitie Continuous Unrealized Loss Position Less Than 12 Months Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securitie Continuous Unrealized Loss Position Less Than 12 Months Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized Losses Less Than 12 Months, Unrealized losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued tax-related interest or penalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value, measurement recurring basis, asset, transfers, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other (expense) income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MrkdgLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">MRKDG License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MrkdgLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">MRKDG License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MrkdgLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">MRKDG License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Additional Paid in Capital, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Additional Paid in Capital, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Additional Paid in Capital, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in-capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred State and Local Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State and local</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion Of Stock Shares Issued1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of shares issued upon conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of Shares, Unvasted Restricted Stock, Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of Shares, Unvasted Restricted Stock, Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Outstanding as of December 31, 2021</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share based compensation by share based payment arrangement equity instruments other than options outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation By Share Based Payment Arrangement Equity Instruments Other Than Options Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested restricted stock as of December 31, 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Income tax benefit (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax benefit (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Income tax benefit (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Unrealized Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Securities, Available-for-Sale, Unrealized Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Debt Securities, Available-for-Sale, Unrealized Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesSubscribedButUnissued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Subscribed but Unissued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesSubscribedButUnissued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity, Shares Subscribed but Unissued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Productive Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Productive Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of PRV related obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesPurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Common Stock Shares Purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesPurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Shares Purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_CommonStockSharesPurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock Shares Purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of common stock, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share Based Compensation Arrangement By Share Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsidiary, Ownership Percentage, Noncontrolling Owner</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ownership percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration of Credit Risk and Other Risks and Uncertainties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseRemainingLeaseTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee operating lease renewal lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByLiabilityClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Recorgnise</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance Stock Options Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PerformanceStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance Stock Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, by Class of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity By Class Of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-Average Remaining Contractual Term, Exercisable at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value of Financial Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value of Financial Instruments, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reductions based on tax positions related to prior year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Reductions based on tax positions related to prior year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontLicenseFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront license fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontLicenseFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upfront License Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_UpfrontLicenseFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront License Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Total deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LesseeOperatingLeaseIncrementalBorrowingRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee operating lease incremental borrowing rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LesseeOperatingLeaseIncrementalBorrowingRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Operating Lease Incremental Borrowing Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_LesseeOperatingLeaseIncrementalBorrowingRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee operating lease incremental borrowing rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock issued in IPO, net of issuance costs of $16,995, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRV-RelatedObligationPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PRV-Related Obligation Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRV-RelatedObligationPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PRV-Related Obligation Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PRV-RelatedObligationPaymentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PRV-Related Obligation Payment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss per share, basic and diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net (loss) income per share - diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available For Sale Securities Continuous Unrealized Loss Position More Than 12 Months Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Continuous Unrealized Loss Position More Than 12 Months Accumulated Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThan12MonthsAccumulatedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized losses 12 months or greater unrealized losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Commitment, Excluding Long-Term Commitment [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsFiniteLivedPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Finite-Lived, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsFiniteLivedPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based compensation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-Based compensation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_Share-BasedCompensationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-Based compensation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Assets, Tax Credit Carryforwards, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Credit Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Research and development tax credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development tax credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Payments Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone Payments Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future milestone payments received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityRedemptionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary Equity Issue Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityRedemptionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Redemption Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TaxCreditCarryforwardExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tax Credit Carryforward, Expiration Year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TaxCreditCarryforwardExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Credit Carryforward Expiration Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TaxCreditCarryforwardExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax Credit Carryforward, Expiration Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_OtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalStockCompensationExpenseStockOptionAwardsGrantedToEmployees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Stock Compensation Expense, Stock option Awards Granted To Employees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalStockCompensationExpenseStockOptionAwardsGrantedToEmployees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Incremental Stock Compensation Expense, Stock option Awards Granted To Employees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_IncrementalStockCompensationExpenseStockOptionAwardsGrantedToEmployees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental stock compensation expense, stock option awards granted to employees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVested_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average remaining lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumToVolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Premium to volume weighted average price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumToVolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Premium To Volume Weighted Average Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PremiumToVolumeWeightedAveragePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Premium To Volume Weighted Average Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Orphan drug credit, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Orphan drug credit, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeFairValueOfDerivativeLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative liability at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeFairValueOfDerivativeLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Derivative Liability, Fair Value, Gross Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeFairValueOfDerivativeLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Liability, Subject to Master Netting Arrangement, before Offset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Property and equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyFourPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyFourPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty Four Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TwoThousandTwentyFourPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024 Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativesOffsettingFairValueAmountsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative Tranches Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativesOffsettingFairValueAmountsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivatives, Offsetting Fair Value Amounts, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_TransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Payments of stock issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments of Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DefinedContributionPlanNumberOfEligibleParticipants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Eligible Participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DefinedContributionPlanNumberOfEligibleParticipants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan Number Of Eligible Participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DefinedContributionPlanNumberOfEligibleParticipants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined Contribution Plan Number Of Eligible Participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term portion of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Long-term portion of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Inputs, Level 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class Of Stock [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureTextBlockAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Text Block [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nontaxable or nondeductible items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorLocation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredTaxAssetsFederalAndStateNetOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Assets, Federal and state net operating loss carryforwards.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredTaxAssetsFederalAndStateNetOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets Federal And State Net Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DeferredTaxAssetsFederalAndStateNetOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal and state net operating loss carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense) [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-operating income:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeContractTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Derivative Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Government Corporations and Agencies Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. government agency securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndExperimentalExpensesAmortizationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research and Experimental Expenses Amortization Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndExperimentalExpensesAmortizationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Experimental Expenses Amortization Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_ResearchAndExperimentalExpensesAmortizationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and experimental expenses amortization period</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Jurisdiction [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DefinedContributionPlanEmployerMatchingContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined Contribution Plan Employer Matching Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_DefinedContributionPlanEmployerMatchingContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan Employer Matching Contribution</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MabcareLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">MabCare License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MabcareLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">MabCare License Agreement [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentOfAccruedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of accrued interest.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_SummaryOfPerformanceStockUnitsActivity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of Performance Stock Units activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Price</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentToObligationOfLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment to Obligation of License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentToObligationOfLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment to Obligation of License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_PaymentToObligationOfLicenseAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment to obligation of license agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement Axis</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorOpinionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Opinion [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_JanssenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Janssen License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_JanssenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Janssen License Agreement [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Four</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentCapitalizedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone Payment Capitalized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_MilestonePaymentCapitalizedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Payment Capitalized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dawn_EmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Purchase Plan [Member]</link:label>
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  <xsd:element id="dawn_AccountsReceivableCreditLosses" name="AccountsReceivableCreditLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefitsPercent" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefitsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_NoncurrentMember" name="NoncurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CashPaymentAgainstMilestoneAchievementPerShare" name="CashPaymentAgainstMilestoneAchievementPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_WeightedAveragePriceOfCompanysCommonStock" name="WeightedAveragePriceOfCompanysCommonStock" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_ResearchAndExperimentalExpensesAmortizationPeriod" name="ResearchAndExperimentalExpensesAmortizationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AgreementDomain" name="AgreementDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AccruedFederalAndStatePayables" name="AccruedFederalAndStatePayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_EmployeeRelatedExpenses" name="EmployeeRelatedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_SeriesBRedeemableConvertiblePreferredSharesMember" name="SeriesBRedeemableConvertiblePreferredSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AccruedMilestonePayment" name="AccruedMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_PreFundedWarrantMember" name="PreFundedWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CommonStockToBeIssuedUnderTheEsppTableTextBlock" name="CommonStockToBeIssuedUnderTheEsppTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_MilestoneCashPaymentReceivedPerShare" name="MilestoneCashPaymentReceivedPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_IpsenLicenseAgreementMember" name="IpsenLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_BalanceSheetItemsLinesItems" name="BalanceSheetItemsLinesItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_TwoCustomerMember" name="TwoCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember" name="TwoThousandAndTwentyOneEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PrepaidExpensesAndOtherCurrentAssetTextBlock" name="PrepaidExpensesAndOtherCurrentAssetTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_CashEquivalentsUnrealizedGains" name="CashEquivalentsUnrealizedGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_OtherMember" name="OtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AdditionalMilestonePayments" name="AdditionalMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_PremiumToVolumeWeightedAveragePrice" name="PremiumToVolumeWeightedAveragePrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_SalesAgreementMember" name="SalesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_TakedaMember" name="TakedaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_BrisbaneCaliforniaMember" name="BrisbaneCaliforniaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue" name="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_Share-BasedCompensationArrangementByShare-BasedPaymentAwardOptionsUnvestedInPeriodFairValue" name="Share-BasedCompensationArrangementByShare-BasedPaymentAwardOptionsUnvestedInPeriodFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_UnamortizedStockBasedCompensationForStockOptions" name="UnamortizedStockBasedCompensationForStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_EmergingGrowthCompanyStatusPolicyTextBlock" name="EmergingGrowthCompanyStatusPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_TransactionPrice" name="TransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_OneCustomerMember" name="OneCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PaymentOfAccruedInterest" name="PaymentOfAccruedInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_RedeemableNonControllingInterestTextBlock" name="RedeemableNonControllingInterestTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_JanssenLicenseAgreementMember" name="JanssenLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_MrkdgLicenseAgreementMember" name="MrkdgLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CashEquivalentsUnrealizedLosses" name="CashEquivalentsUnrealizedLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_PaymentToObligationOfLicenseAgreement" name="PaymentToObligationOfLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_NetProductRevenueAndAccountsReceivableMember" name="NetProductRevenueAndAccountsReceivableMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SeriesARedeemableConvertiblePreferredStockMember" name="SeriesARedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_DisclosureDetailsOfActivitiesRelatingToIncentiveSharesTableTextBlock" name="DisclosureDetailsOfActivitiesRelatingToIncentiveSharesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_RedeemableNoncontrollingInterestPolicyTextBlock" name="RedeemableNoncontrollingInterestPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_SummaryOfPerformanceStockUnitsActivity" name="SummaryOfPerformanceStockUnitsActivity" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_IncomeTaxReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefits" name="IncomeTaxReconciliationNondeductibleExpenseChangesInUnrecognizedTaxBenefits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock" name="DeferredFinanceIssuanceCostsPolicyTextBlockPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AccruedRebates" name="AccruedRebates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_OptionRepricingMember" name="OptionRepricingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_XOMALicenseAgreementMember" name="XOMALicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_ScheduleOfChangesInTheValuationAllowanceForDeferredTaxAssets" name="ScheduleOfChangesInTheValuationAllowanceForDeferredTaxAssets" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_EffectiveIncomeTaxRateTotal" name="EffectiveIncomeTaxRateTotal" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_ScheduleOfPerformanceStockOptionsAssumptionsTableTextBlock" name="ScheduleOfPerformanceStockOptionsAssumptionsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_MilestonePaymentsNotYetPaid" name="MilestonePaymentsNotYetPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_OtherAdjustmentsMember" name="OtherAdjustmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CommonStockSharesIssuedAsAResultOfConversionOfTemporaryEquityIntoPermanentEquity" name="CommonStockSharesIssuedAsAResultOfConversionOfTemporaryEquityIntoPermanentEquity" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_ScheduleOfStockOptionsAssumptionsTableTextBlock" name="ScheduleOfStockOptionsAssumptionsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionAccumulatedLoss" name="AvailableForSaleSecuritieContinuousUnrealizedLossPositionAccumulatedLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_RoyaltyFeePayable" name="RoyaltyFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_IndividualCustomerMember" name="IndividualCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SprintBioscienceAgreementMember" name="SprintBioscienceAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_VolumeWeightedAveragePrice" name="VolumeWeightedAveragePrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_CostOfLicenseRevenuePolicyTextBlock" name="CostOfLicenseRevenuePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AggregateOfUpfrontLicenseFeeReceived" name="AggregateOfUpfrontLicenseFeeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_CommonStockSharesPurchased" name="CommonStockSharesPurchased" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_DepositsAndOtherLongtermAssetsNonCurrent" name="DepositsAndOtherLongtermAssetsNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_Third-PartyCROCMOAndOtherThird-PartyClinicalTrialCosts" name="Third-PartyCROCMOAndOtherThird-PartyClinicalTrialCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_MabcareLicenseAgreementMember" name="MabcareLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PatentCostsPolicytextblock" name="PatentCostsPolicytextblock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AgreementAxis" name="AgreementAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SharesCommittedUnderESPPMember" name="SharesCommittedUnderESPPMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_JeremyBenderMember" name="JeremyBenderMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_ViractaLicenseAgreementMember" name="ViractaLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SamuelBlackmanMember" name="SamuelBlackmanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SeriesBRedeemableConvertiblePreferredStockMember" name="SeriesBRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_UnvestedCommonSharesMember" name="UnvestedCommonSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_MarketableSecuritiesMember" name="MarketableSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PRVRelatedObligationAmount" name="PRVRelatedObligationAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_LeaseForCorporateOfficeFacilityMember" name="LeaseForCorporateOfficeFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_MilestonePaymentsReceived" name="MilestonePaymentsReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_DetailsDomain" name="DetailsDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_ConditionsForIssueDomain" name="ConditionsForIssueDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PRV-RelatedObligationPaymentMember" name="PRV-RelatedObligationPaymentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CharlesYorkMember" name="CharlesYorkMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AccruedMilestoneLiability" name="AccruedMilestoneLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_UpfrontPayment" name="UpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_UnvestedCommonStockMember" name="UnvestedCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_TwoThousandAndTwentyOneEquityIncentivePlanMember" name="TwoThousandAndTwentyOneEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_ExternalCostsAbstract" name="ExternalCostsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PremiumReceivedOnLicenseAgreement" name="PremiumReceivedOnLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_UndeliveredRelapsedOrRefractoryFront-LineAndCompanionDiagnosticResearchAndDevelopmentServicesMember" name="UndeliveredRelapsedOrRefractoryFront-LineAndCompanionDiagnosticResearchAndDevelopmentServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_SummaryOfPerformanceStockOptions" name="SummaryOfPerformanceStockOptions" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingTerm" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_LicenseAgreementMilestonePaymentMember" name="LicenseAgreementMilestonePaymentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" name="AvailableForSaleSecuritieContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_TemporaryEquitySharesConvertedIntoPermanentEquity" name="TemporaryEquitySharesConvertedIntoPermanentEquity" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_AggregateCashConsiderationPaid" name="AggregateCashConsiderationPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_ConcentrationOfCreditRiskAndOtherRisksAndUncertaintiesMember" name="ConcentrationOfCreditRiskAndOtherRisksAndUncertaintiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_AccruedResearchAndDevelopmentExpenses" name="AccruedResearchAndDevelopmentExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dawn_NetOperatingLossCarrybackPeriod" name="NetOperatingLossCarrybackPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_LicenseAgreementWithIpsenPharmaSasMember" name="LicenseAgreementWithIpsenPharmaSasMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_PrvPressureReliefValveMember" name="PrvPressureReliefValveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_ScheduleOfMaturitiesForAvailableForSaleSecuritiesTableTextBlock" name="ScheduleOfMaturitiesForAvailableForSaleSecuritiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_TwoThousandAndTwentyOneStockIncentivePlanMember" name="TwoThousandAndTwentyOneStockIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dawn_CashPaymentAgainstMilestoneAchievement" name="CashPaymentAgainstMilestoneAchievement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_LesseeOperatingLeaseIncrementalBorrowingRate" name="LesseeOperatingLeaseIncrementalBorrowingRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_UpfrontLicenseFee" name="UpfrontLicenseFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_PaymentOfMilestones" name="PaymentOfMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dawn_TemporaryEquityStockIssuedDuringThePeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringThePeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding" name="ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dawn_TaxCreditCarryforwardExpirationYear" name="TaxCreditCarryforwardExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dawn_DefinedContributionPlanEmployerMatchingContribution" name="DefinedContributionPlanEmployerMatchingContribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
