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          <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="dftx_ShareBasedPaymentArrangementDirectorsDeferredShareUnitPlanActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Directors' Deferred Share Unit Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedPaymentArrangementDirectorsDeferredShareUnitPlanActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Directors' Deferred Share Unit Plan, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedPaymentArrangementDirectorsDeferredShareUnitPlanActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-based payment arrangement, directors' deferred share unit plan, activity.</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_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="dftx_WeightedAverageFairValueOfSharesPurchasedUponExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average fair value of shares purchased upon exercise of warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageFairValueOfSharesPurchasedUponExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Fair Value Of Shares Purchased Upon Exercise Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageFairValueOfSharesPurchasedUponExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average fair value of shares purchased upon exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtInstrumentExtendedMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Extended Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtInstrumentExtendedMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument extended maturity date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtInstrumentExtendedMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument extended maturity date</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_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average exercise price, expired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price</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="us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expenses, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and Administrative</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 shareholders' 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="dftx_K2HealthventuresLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">K2 HealthVentures LLC.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_K2HealthventuresLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">K2 HealthVentures LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_K2HealthventuresLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">K2HV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubordinateVotingSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subordinate voting shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubordinateVotingSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subordinate Voting Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubordinateVotingSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subordinate Voting Shares</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 equivalents</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_SharesIssuedPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issued, Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesIssuedPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued, price per share</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="dftx_DebtInstrumentConvertibleConvertedIntoCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Converted into common shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtInstrumentConvertibleConvertedIntoCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">DebtInstrument Convertible Converted Into Common Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtInstrumentConvertibleConvertedIntoCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debtinstrument convertible converted into common shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Goodwill, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Goodwill, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Goodwill, 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">Stock Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearTwoBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt repayments of principal in year two before unamortized debt issuance cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearTwoBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Repayments of Principal in Year Two Before Unamortized Debt Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearTwoBeforeUnamortizedDebtIssuanceCost_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_AdditionalPaidInCapitalCommonStock_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_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Additional Paid in Capital, Common Stock, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Additional Paid in Capital, Common Stock, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Risk Free Interest Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember_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_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Intangible assets, useful life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, Useful Lives (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible assets (acquired technology), Useful life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VestingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting [Domain]</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">Number of options, granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Computation of Basic and Diluted Net Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Underwritten offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwritten Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwritten Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2026 Underwritten Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OptionsIssuedAndOutstandingUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options Issued and Outstanding Under Stock Option Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OptionsIssuedAndOutstandingUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Options Issued and Outstanding Under Stock Option Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OptionsIssuedAndOutstandingUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Options issued and outstanding under stock option plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments Classified by Contractual Maturity Date [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Maturities of Company's Investment</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>
          <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/terseLabel">Basic</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/verboseLabel">Net loss per common share, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesPurchasedOptionsPricePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Premium on Purchased Options [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesPurchasedOptionsPricePolicy_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_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on foreign currency translation</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 options, outstanding</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of options, outstanding</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/terseLabel">Common shares subject to outstanding option awards</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/verboseLabel">Number of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of 2022 USD Financing Warrants to common shares upon exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued</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_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_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net loss to net cash used in operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DirectorsDeferredShareUnitsLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Directors' Deferred Share Unit Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DirectorsDeferredShareUnitsLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">DDSU Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DirectorsDeferredShareUnitsLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Directors' deferred share units liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WithholdingTaxesPayableOnOptionExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Withholding Taxes Payable on Option Exercises</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WithholdingTaxesPayableOnOptionExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Withholding taxes payable on option exercises.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WithholdingTaxesPayableOnOptionExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Withholding taxes payable on option exercises</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Axis]</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>
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          <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/verboseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearThreeBeforeUnamortizedDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt repayments of principal in year three before unamortized debt issuance costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearThreeBeforeUnamortizedDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Repayments of Principal in Year Three Before Unamortized Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearThreeBeforeUnamortizedDebtIssuanceCosts_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_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_AccountingStandardsUpdate201602Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2016-02</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of the Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operations [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of options, forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance Initial Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from equity offerings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share issued price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Outstanding, Measurement Input</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based Compensation</link:label>
          <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="dftx_StockIssuedDuringPeriodSharesWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period shares warrants exercised.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Shares Warrants Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of Warrants, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted, Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Diluted, Adjustment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental shares from 2022 USD Financing Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value, cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Weighted average grant date fair value, cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cancelled in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-based compensation arrangement by share-based payment award, equity instruments other than options, cancelled in period, weighted average grant date fair value.</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="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="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_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 Shareholders&#8217; 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/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/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update and Change in Accounting Principle [Table]</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_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average exercise price, issued</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/verboseLabel">Weighted average exercise price, granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Effective Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument interest rate</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="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in accounting principle, accounting standards update, immaterial effect [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of assets transfers out of Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3</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">Schedule of Fair Value Assumptions of Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities [Table]</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="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/totalLabel">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/label">Income Tax, Policy [Policy Text Block]</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="dftx_BoughtDealFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bought deal financing.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_BoughtDealFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bought Deal Financing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_BoughtDealFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bought Deal Financing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental Cash Flow Information</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Currency Transactions and Translations Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of Warrant or Right</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement and Arrangement Other than Collaborative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentyTwoUsdFinancingWarrantLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 USD Financing Warrant Liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentyTwoUsdFinancingWarrantLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty two usd financing warrant liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement and Arrangement Other than Collaborative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of available-for-sale investments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase/(decrease) in cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive securities excluded from computation of loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfAdoptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AmortizationOfDeferredFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amortization of deferred financing costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AmortizationOfDeferredFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of deferred financing costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining contractual life (Years), outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_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, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility, maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WorkersCompensationLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WorkersCompensationLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Workers' Compensation Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Debt Securities Available-for-sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of options, exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of stock options, net of shares withheld for exercise and tax, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Shares Conversion Of Term Loan Principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period shares conversion of term loan principal.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common shares upon conversion of term loan principal, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateNumberOfCommonSharesOwnedByHolderPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate number of common shares owned by holder percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateNumberOfCommonSharesOwnedByHolderPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Number Of Common Shares Owned By Holder Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateNumberOfCommonSharesOwnedByHolderPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate number of common shares owned by holder percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, by Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value By Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, State or Province</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/periodStartLabel">Number of shares, beginning balance</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">Number of shares, ending balance</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/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_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Financial liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">DDSU Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at June 30, 2026</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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss and comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized Gain</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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubordinateVotingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Subordinate Voting Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubordinateVotingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subordinate voting.</link:label>
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          <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="us-gaap_ClassOfWarrantOrRightDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of Warrant or Right</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityLenderDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Lender [Domain]</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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AdjustmentsToAdditionalPaidInCapitalAmortizationOfDeferredATMCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to Additional Paid in Capital, Amortization of deferred ATM costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PerformanceSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PerformanceSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance shares units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwritten Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwritten Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Underwritten public offering 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/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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInDirectorsDeferredShareUnit-RelatedAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Director's Deferred Share Unit-related Accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInDirectorsDeferredShareUnit-RelatedAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in director&#8217;s deferred share unit-related accruals.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInDirectorsDeferredShareUnit-RelatedAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in director's deferred share unit-related accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnvestedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested RSUs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnvestedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unvested Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnvestedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unvested restricted stock units (RSUs).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ExerciseOfWarrantShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercise of Warrant shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ExerciseOfWarrantShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ExerciseOfWarrantShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise of Warrant shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unamortized debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Expected Term [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfCommonSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average shares used in computing net loss per share attributable to common shareholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfCommonSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Of Common Shares Outstanding Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfCommonSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average number of common shares outstanding basic.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of options, expired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of options, expired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Expirations in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Presentation and Summary of Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IndicationOfImpairmentOfGoodwillAndLongLivedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Indication of impairment of goodwill and long-lived assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IndicationOfImpairmentOfGoodwillAndLongLivedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indication of Impairment of Goodwill and Long-lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IndicationOfImpairmentOfGoodwillAndLongLivedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indication of impairment of goodwill and long-lived assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated OCI</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Impairment Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment charges of goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleBeneficialConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Beneficial Conversion Feature</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleBeneficialConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument convertible, conversion feature principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, maturity date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Fair Value of Amount Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of credit facility</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/terseLabel">Weighted average grant date fair value, granted</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_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="dftx_SharesAvailableForGrantUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Available for Grant Under Stock Option Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SharesAvailableForGrantUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Available for Grant Under Stock Option Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SharesAvailableForGrantUnderStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares available for grant under stock option plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Number of Securities Called by Each Warrant or Right</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares purchasable for each warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OtherNonCashAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other non-cash adjustments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OtherNonCashAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Non Cash Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OtherNonCashAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-cash adjustments</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/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/totalLabel">Amortization of Intangible Assets, Total</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">Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLongTermLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Long-Term Lines of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLongTermLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from credit facility</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/terseLabel">Schedule of Assets and Liabilities Measured at Fair Value 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/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_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Combinations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrealizedGainLossOnInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrealized Gain (Loss) on Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrealizedGainLossOnInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized gain/(loss) on investments</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_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_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance, Shares</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 10)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CadFinancingAndCompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">CAD financing and compensation warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CadFinancingAndCompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">CAD Financing And Compensation Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CadFinancingAndCompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CAD financing and Compensation Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalRemainderOfFiscalYearBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt repayments of principal, remainder of fiscal year, before unamortized debt issuance cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalRemainderOfFiscalYearBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Repayments Of Principal Remainder Of Fiscal Year Before Unamortized Debt Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalRemainderOfFiscalYearBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remainder of 2026</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_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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Term Loan bears a variable interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reverse stock split description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity, Reverse Stock Split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockNoParValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, no par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockNoParValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, No Par Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After Two Through Three Years Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available for sale securities debt maturities after two through three years fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value, Due in two to three years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_EquityOfferingCostsInPrepaidsAndOtherCurrentAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Offering Costs in Prepaids and Other Current Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_EquityOfferingCostsInPrepaidsAndOtherCurrentAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity offering costs in prepaids and other current assets, net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_EquityOfferingCostsInPrepaidsAndOtherCurrentAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity offering costs in prepaids and other current assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes on cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachUnit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class of warrant or right number of securities called by each unit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachUnit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class Of Warrant Or Right Number Of Securities Called By Each Unit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachUnit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares purchasable for each unit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_USDFinancingWarrantsNotIncludedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">USD Financing Warrants Not Included</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_USDFinancingWarrantsNotIncludedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">USD Financing Warrants Not Included [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_USDFinancingWarrantsNotIncludedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">USD Financing Warrants Not Included [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average common shares, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total weighted-average shares used in computing net loss per share attributable to common shareholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Acquired During Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill acquired during period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfDilutedPreFundedWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Of Diluted Pre Funded Warrants Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfDilutedPreFundedWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average number of diluted pre funded warrants outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfDilutedPreFundedWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average pre-funded warrants used in computing net loss per share attributable to common shareholders, diluted</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="dftx_OtherLiabilitiesLongTerm_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other liabilities, long-term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OtherLiabilitiesLongTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Long-Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_OtherLiabilitiesLongTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other liabilities, long-term.</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net proceeds from private placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Recognized of incremental compensation cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value</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">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/periodStartLabel">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/totalLabel">Total shareholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Investments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchases of investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedExpensesIncludingAccruedCompensationAndAccruedClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Expenses Including Accrued Compensation and Accrued Clinical Trial Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedExpensesIncludingAccruedCompensationAndAccruedClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in accrued expenses including accrued compensation and accrued clinical trial costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedExpensesIncludingAccruedCompensationAndAccruedClinicalTrialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in accrued expenses including accrued compensation and accrued clinical trial costs</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/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_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AccruedOtherResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Other Research and Development Costs Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AccruedOtherResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued other research and development costs current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AccruedOtherResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued other research and development costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Tranche Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAwardTrancheTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tranche Two</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/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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OverAllotmentOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Over-Allotment Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OverAllotmentOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Over-Allotment Option [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Foreign exchange</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Realized and unrealized gains and losses from foreign exchange</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Foreign Currency Transaction Gain (Loss), before Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss), Foreign Currency Transaction, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign exchange loss, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_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_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After One Through Two Years Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available for sale securities debt maturities after one through two years fair value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value, Due in one to two years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsNoteDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Note Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationDateOfIncorporation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, Date of Incorporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationDateOfIncorporation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity date of incorporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Accrued Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncash Investing and Financing Items [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental Noncash Disclosures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of shares, cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cancelled in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-based compensation arrangement by share-based payment award, equity instruments other than options, cancelled in period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</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_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Operating and Nonoperating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MultipleVotingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Multiple voting.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MultipleVotingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Multiple Voting [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MultipleVotingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Multiple Voting</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">Weighted average exercise price, vested and exercisable</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRights_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRights_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting rights, description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ScheduleOfWarrantLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Warrant Liability [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ScheduleOfWarrantLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of warrant liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ScheduleOfWarrantLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Activity of Outstanding Warrant Liability</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_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at December 31, 2025</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/periodEndLabel">Balance at June 30, 2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class Of Warrant Or Right [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair value of liabilities transfers into Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FirstTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">First tranche term loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FirstTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">First Tranche Term Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FirstTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">First Tranche Term Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LongTermInvestmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long Term Investments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LongTermInvestmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LongTermInvestmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Investments [Member]</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="dftx_PerformanceAndRestrictedShareUnitPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PRSU Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PerformanceAndRestrictedShareUnitPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance And Restricted Share Unit Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PerformanceAndRestrictedShareUnitPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance And Restricted Share Unit Plan Member.</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="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="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="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfEquityRemainingOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of equity, remaining offering amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfEquityRemainingOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale Of Equity Remaining Offering Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfEquityRemainingOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of securities remaining availablility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total principal repayments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityBankruptcyProceedingsReportingCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Bankruptcy Proceedings, Reporting Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityBankruptcyProceedingsReportingCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Bankruptcy Proceedings, Reporting Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [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/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IssuanceOfCommonSharesUponConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Common Shares Upon Conversion Of Term Loan Principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IssuanceOfCommonSharesUponConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of common shares upon conversion of term loan principal.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IssuanceOfCommonSharesUponConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common shares upon conversion of term loan principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants disclosure.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Paid, Excluding Capitalized Interest, Operating Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for interest and final payment for credit facility</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="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common shares at an initial excercise price</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/periodEndLabel">Ending balance, weighted average exercise price</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/periodStartLabel">Beginning balance, weighted average exercise price</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">Warrant exercise price</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/terseLabel">Stock-based compensation</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">Total 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/label">Stock-based compensation expense recognized</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="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="dftx_ProceedsFromExerciseOfPre-FundedWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of pre-funded warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromExerciseOfPre-FundedWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Exercise Of Pre-funded Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromExerciseOfPre-FundedWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from e xercise of pre-funded warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Financing warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financing Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing Warrants</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/terseLabel">RSUs</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_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_VestingAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting [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/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_WarrantsAndRightsOutstandingMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Outstanding, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingExcludingDiscountsAndCommissionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwritten Offering Excluding Discounts and Commissions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingExcludingDiscountsAndCommissionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Underwritten offering excluding discounts and commissions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UnderwrittenOfferingExcludingDiscountsAndCommissionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwritten Offering Excluding Discounts and Commissions</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="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="dftx_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction Costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Requisite service period</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/terseLabel">Weighted-average common shares, 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">Total weighted-average shares used in computing net loss per share attributable to common shareholders, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesUponSettlementOfRestrictedStockUnitAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Shares Upon Settlement Of Restricted Stock Unit Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesUponSettlementOfRestrictedStockUnitAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period Shares Upon Settlement Of Restricted Stock Unit Awards.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodSharesUponSettlementOfRestrictedStockUnitAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common shares upon settlement of restricted share unit ("RSU") awards, Shares</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_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="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, minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants policy.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants</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/label">Prepaid Expense and Other Assets, Current</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/terseLabel">Prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of liabilities transfers out of Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrealized Gain (Loss), Foreign Currency Transaction, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unrealized foreign exchange</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="dftx_SaleOfStockNumberOfAdditionalSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of stock, number of additional shares issued in transaction.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfStockNumberOfAdditionalSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Number Of Additional Shares Issued in Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfStockNumberOfAdditionalSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Public offering, additional shares issued (in shares)</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/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/totalLabel">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/terseLabel">General and administrative</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="dftx_SaleOfEquityAggregatePublicOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of securities aggregate public offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfEquityAggregatePublicOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale Of Equity Aggregate Public Offering Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SaleOfEquityAggregatePublicOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale Of equity aggregate public offering amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private placement shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on extinguishment of contribution payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Extinguishment of Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain on extinguishment of contribution payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period value warrants exercised.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value Warrants Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueWarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of Warrants</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_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Pronouncements</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Liabilities Fair Value Disclosure [Abstract]</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 rate, minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized tax benefits, interest charges or penalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-Term Investments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-term investments</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="dftx_ResearchAndDevelopmentInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Internal Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ResearchAndDevelopmentInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research and development internal expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ResearchAndDevelopmentInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Internal expenses</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="dftx_GeneralAndAdministrativeInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Internal expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_GeneralAndAdministrativeInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Internal Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_GeneralAndAdministrativeInternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">General and administrative internal expense .</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_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</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/totalLabel">Total operating expenses</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</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/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearFourBeforeUnamortizedDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt repayments of principal in year four before unamortized debt issuance costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearFourBeforeUnamortizedDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Repayments of Principal in Year Four Before Unamortized Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInYearFourBeforeUnamortizedDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</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/terseLabel">Issuance of common shares, net of shares issuance cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock Option Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial Assets, Fair Value Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure [Abstract]</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">Shareholders&#8217; Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 USD Financing Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financing Warrants Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_FinancingWarrantsLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Financing warrants liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Restricted Share Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Exercised, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants exercised.</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_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss attributable to common shareholders</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/2003/role/periodEndLabel">Aggregate intrinsic value, 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/periodStartLabel">Aggregate intrinsic value, outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateInducementAwardsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Inducement Awards Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateInducementAwardsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate inducement awards outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AggregateInducementAwardsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate inducement awards outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PercentageOfGrossProceedsSaleOfCommonSharesPayableAsSalesAgentsCommissionRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of gross proceeds from sales of common shares payable as sales agent commission rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PercentageOfGrossProceedsSaleOfCommonSharesPayableAsSalesAgentsCommissionRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Gross Proceeds Sale Of Common Shares Payable As Sales Agents Commission Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PercentageOfGrossProceedsSaleOfCommonSharesPayableAsSalesAgentsCommissionRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of gross proceeds sale of common shares payable as sales agents commission rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Outstanding, Term</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">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/terseLabel">Expected dividend yield</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfPreFundedWarrantsOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average pre-funded warrants used in computing net loss per share attributable to common shareholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfPreFundedWarrantsOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Of Pre Funded Warrants Outstanding Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WeightedAverageNumberOfPreFundedWarrantsOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average number of pre funded warrants outstanding basic.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ResearchAndDevelopmentExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development External Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ResearchAndDevelopmentExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research and development external expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ResearchAndDevelopmentExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_InducementEquityAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inducement Equity Awards [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_InducementEquityAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">inducement equity awards member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_InducementEquityAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inducement Equity Awards</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/periodEndLabel">Aggregate intrinsic value, vested and exercisable</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">Aggregate intrinsic value, vested and exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LeaseLiabilitiesArisingFromObtainingRight-Of-UseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Liabilities Arising from Obtaining Right-Of-Use Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LeaseLiabilitiesArisingFromObtainingRight-Of-UseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease liabilities arising from obtaining right-of-use assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_LeaseLiabilitiesArisingFromObtainingRight-Of-UseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease liabilities arising from obtaining right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Prepaid Expense and Other Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid and other current assets</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="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UsdFinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 USD Financing Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UsdFinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2022 USD Financing Warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_UsdFinancingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">2022 USD Financing Warrants [Member]</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_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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201912Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2019-12</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201912Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2019-12 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of options</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="dftx_GeneralAndAdministrativeExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_GeneralAndAdministrativeExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative External Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_GeneralAndAdministrativeExternalExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">General and administrative external expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputSharePriceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputSharePriceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Share Price [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Available to Common Stockholders, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Available to Common Stockholders, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss attributable to common shareholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Line of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-Term Line of Credit, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument</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="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial assets</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_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common shares under ESPP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Excluding Option Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Placement</link:label>
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          <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>
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          <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="dftx_VestedAndUnissuedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vested and Unissued RSUs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_VestedAndUnissuedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vested and Unissued Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_VestedAndUnissuedRestrictedStockUnitsRsusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Vested and unissued restricted stock units (RSUs).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SummaryOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Shares Reserved for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SummaryOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of shares reserved for issuance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SummaryOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Shares Reserved For Issuance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestructuredAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructured Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestructuredAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructured Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestructuredAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restructured Agreement</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 non-current liabilities</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="dftx_CommonShareAndWarrantPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Share and Warrant Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CommonShareAndWarrantPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Share and Warrant Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CommonShareAndWarrantPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Share and Warrant Public Offering Member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities:</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/periodEndLabel">Weighted average exercise price, outstanding</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, outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_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="dftx_CovenantShallBeWaivedDuringMarketCapitalizationExceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Covenant shall be waived during market capitalization exceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CovenantShallBeWaivedDuringMarketCapitalizationExceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Covenant Shall be Waived During Market Capitalization Exceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CovenantShallBeWaivedDuringMarketCapitalizationExceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Covenant shall be waived during market capitalization exceeds.</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="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="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements or Change in Accounting Principle [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in accounting principle, accounting standards update, adoption date</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="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 rate, maximum</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, Due 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="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/verboseLabel">Summary of Carrying Value of Intangible Assets</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">Summary of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</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</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">Expected life</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">Recurring</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="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/label">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedPayrollTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Payroll Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedPayrollTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in accrued payroll taxes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_IncreaseDecreaseInAccruedPayrollTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in accrued payroll taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingValuationTechniqueExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants, Valuation Technique [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingValuationTechniqueExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Outstanding, Valuation Technique [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201613Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2016-13</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants issued.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issued, shares</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="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining contractual life (Years), vested and exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_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 Remaining Contractual Term</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_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_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Employee Stock Purchase Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nominal amount of expense in relation to ESPP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of common shares under employee share purchase plan ("ESPP"), Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeInterestAndDividend_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Investment Income, Interest and Dividend, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeInterestAndDividend_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income, Interest and Dividend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeInterestAndDividend_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInNextTwelveMonthsBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt repayments of principal in next twelve months before unamortized debt issuance cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInNextTwelveMonthsBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Repayments of Principal in Next Twelve Months Before Unamortized Debt Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DebtRepaymentsOfPrincipalInNextTwelveMonthsBeforeUnamortizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DirectorsDeferredShareUnitPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Directors' Deferred Share Unit Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_DirectorsDeferredShareUnitPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Directors' Deferred Share Unit Plan [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="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum</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="dftx_AmendmentTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AmendmentTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amendment term loans.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AmendmentTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Term Loans</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">Weighted average exercise price, exercised</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/verboseLabel">Weighted average market price of options exercised</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/terseLabel">Common shares, no par value, unlimited authorized as of June 30, 2026 and December 31, 2025; 134,365,950 and 98,776,265 issued and outstanding as of June 30, 2026 and December 31, 2025, respectively</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Available to Common Stockholders, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss attributable to common shareholders, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Compensation warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CompensationWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Compensation Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CommonShareAndWarrantPublicOfferingExpireDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common share and warrant public offering expire date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CommonShareAndWarrantPublicOfferingExpireDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Share and Warrant Public Offering Expire Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_CommonShareAndWarrantPublicOfferingExpireDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common share and warrant public offering expire date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestrictedShareUnitAwardsAndPerformanceShareUnitAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Share Unit Awards And Performance Share Unit Awards [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestrictedShareUnitAwardsAndPerformanceShareUnitAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted share unit awards and performance share unit awards.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_RestrictedShareUnitAwardsAndPerformanceShareUnitAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Share Unit Awards and Performance Share Unit Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentySixInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026 Inducement Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentySixInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Six Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentySixInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty six inducement plan.</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">Summary of Expected Future Amortization Expense for 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="us-gaap_OtherNonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense) [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income/(expense):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MindMedStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">MindMed stock option plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MindMedStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mind Med Stock Option Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_MindMedStockOptionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">MindMed Stock Option Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExpired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expired, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExpired_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants expired.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_WarrantsExpired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_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="dftx_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre-Funded Warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre Funded Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lender Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]</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">Estimated 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_EmployeeStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated ESPP awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Estimated ESPP shares</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="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax</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">Total other income/(expense), net</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">Total other income/(expense)</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_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="dftx_ProceedsFromOfferingsAndPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from the Offerings and Private Placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromOfferingsAndPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Offerings and Private Placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromOfferingsAndPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from the Offerings and Private Placement.</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 shares, net of issuance costs</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">Net proceeds from 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/label">Proceeds from the 2022 ATM net of issuance costs</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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Assumptions used to Determine Fair Value of 2022 USD Financing Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ChangeInFairValueOnDirectorsDeferredShareUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in fair value on directors' deferred share units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ChangeInFairValueOnDirectorsDeferredShareUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in fair value on directors' deferred share units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ChangeInFairValueOnDirectorsDeferredShareUnits_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value on directors' deferred share units ("DDSU")</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="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</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="dftx_PercentageOfIncreaseOrDecreaseOfOwnershipByPreFundedWarrantsHolder_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Increase Or Decrease Of Ownership By Pre-funded Warrants Holder</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PercentageOfIncreaseOrDecreaseOfOwnershipByPreFundedWarrantsHolder_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of increase or decrease of ownership by pre-funded warrants holder.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_PercentageOfIncreaseOrDecreaseOfOwnershipByPreFundedWarrantsHolder_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of increase or decrease of ownership by pre-funded warrants holder</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="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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares, 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="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After One Through Two Years Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available for sale securities debt maturities after one through two years amortized cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost, Due in one to two years</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/totalLabel">Total assets</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">Stock purchase option, exercisable term</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_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</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_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Number of Shares Issued in Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of 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/verboseLabel">Stock issued during period</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">Issuance of common shares, net of shares issuance cost, Shares</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">Number of shares, 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/2009/role/negatedLabel">Number of shares, vested</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">Earnings Per Share, Diluted, Total</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">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 per common 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">Summary of Additional Expense Details</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="us-gaap_DebtInstrumentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Fee Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued final payment fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubsequentTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subsequent tranche term loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_SubsequentTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent tranche term loan [Member]</link:label>
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          <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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateEarlyAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in accounting principle, accounting standards update, early adoption [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Employee Stock Purchase Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Nominal amount of expense in relation to ESPP recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common shares under employee share purchase plan ("ESPP")</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="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock split conversion ratio</link:label>
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          <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 Equivalents</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="dftx_ConversionSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ConversionSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ConversionSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsFinitelived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of intangible assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of options, vested and exercisable</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">Number of options, vested and exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common shares upon conversion of term loan principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value Conversion Of Term Loan Principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_StockIssuedDuringPeriodValueConversionOfTermLoanPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period value conversion of term loan principal.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_NatureOfOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nature of operations.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_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_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents, beginning of period</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_BusinessCombinationMaximumMeasurementPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, maximum measurement period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_BusinessCombinationMaximumMeasurementPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Maximum Measurement Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_BusinessCombinationMaximumMeasurementPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination, maximum measurement period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember_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_MeasurementInputPriceVolatilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Price Volatility [Member]</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">Payment of share issuance cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of equity offering costs</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">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_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Term loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Term Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Term Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in accounting principle, accounting standards update, adopted [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentyTwoAtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Two At The Market Offering Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentyTwoAtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty two at the market offering program.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_TwoThousandTwentyTwoAtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 At-The-Market Facilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromExerciseOfWarrantsInPrepaidAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Exercise of Warrants in Prepaid and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromExerciseOfWarrantsInPrepaidAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from exercise of warrants in prepaid and other current assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_ProceedsFromExerciseOfWarrantsInPrepaidAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of 2022 USD Financing Warrants in prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]</link:label>
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          <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. agency bonds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share due to Anti-dilutive Effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AccruedClinicalAndManufacturingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued clinical and manufacturing costs.</link:label>
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          <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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AdditionalTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Tranche Term Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AdditionalTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional Tranche Term Loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AdditionalTrancheTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Tranche Term Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Lines of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repayment of credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accretion (Amortization) of Discounts and Premiums, Investments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsAmortizedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost, Due in two to three years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash equivalents</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasisAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasisAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price</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/verboseLabel">Share price</link:label>
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      </link:linkbase>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element id="dftx_IncreaseDecreaseInAccruedExpensesIncludingAccruedCompensationAndAccruedClinicalTrialCosts" name="IncreaseDecreaseInAccruedExpensesIncludingAccruedCompensationAndAccruedClinicalTrialCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_AdjustmentsToAdditionalPaidInCapitalAmortizationOfDeferredATMCosts" name="AdjustmentsToAdditionalPaidInCapitalAmortizationOfDeferredATMCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_AccruedOtherResearchAndDevelopmentCostsCurrent" name="AccruedOtherResearchAndDevelopmentCostsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_CommonShareAndWarrantPublicOfferingExpireDate" name="CommonShareAndWarrantPublicOfferingExpireDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_DebtRepaymentsOfPrincipalInNextTwelveMonthsBeforeUnamortizedDebtIssuanceCost" name="DebtRepaymentsOfPrincipalInNextTwelveMonthsBeforeUnamortizedDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_IncreaseDecreaseInAccruedPayrollTaxes" name="IncreaseDecreaseInAccruedPayrollTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_WarrantsIssued" name="WarrantsIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_ConversionSharesMember" name="ConversionSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_LoanAndSecurityAgreementMember" name="LoanAndSecurityAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AccruedClinicalAndManufacturingCosts" name="AccruedClinicalAndManufacturingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_VestedAndUnissuedRestrictedStockUnitsRsusMember" name="VestedAndUnissuedRestrictedStockUnitsRsusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ChangeInFairValueOnDirectorsDeferredShareUnits" name="ChangeInFairValueOnDirectorsDeferredShareUnits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_StockIssuedDuringPeriodSharesWarrantsExercised" name="StockIssuedDuringPeriodSharesWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_PerformanceAndRestrictedShareUnitPlanMember" name="PerformanceAndRestrictedShareUnitPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_WeightedAverageNumberOfDilutedPreFundedWarrantsOutstanding" name="WeightedAverageNumberOfDilutedPreFundedWarrantsOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_PreFundedWarrantsMember" name="PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_SubordinateVotingSharesMember" name="SubordinateVotingSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_UnvestedRestrictedStockUnitsRsusMember" name="UnvestedRestrictedStockUnitsRsusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_PercentageOfGrossProceedsSaleOfCommonSharesPayableAsSalesAgentsCommissionRate" name="PercentageOfGrossProceedsSaleOfCommonSharesPayableAsSalesAgentsCommissionRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_WarrantsExercised" name="WarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_BusinessCombinationMaximumMeasurementPeriod" name="BusinessCombinationMaximumMeasurementPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_DebtRepaymentsOfPrincipalInYearFourBeforeUnamortizedDebtIssuanceCosts" name="DebtRepaymentsOfPrincipalInYearFourBeforeUnamortizedDebtIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_TwoThousandTwentyFourAtTheMarketOfferingProgramMember" name="TwoThousandTwentyFourAtTheMarketOfferingProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ProceedsFromExerciseOfWarrantsInPrepaidAndOtherCurrentAssets" name="ProceedsFromExerciseOfWarrantsInPrepaidAndOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_ProceedsFromExerciseOfPre-FundedWarrants" name="ProceedsFromExerciseOfPre-FundedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_WarrantsDisclosureTextBlock" name="WarrantsDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_OtherNonCashAdjustments" name="OtherNonCashAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_UsdFinancingWarrantsMember" name="UsdFinancingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_SaleOfEquityAggregatePublicOfferingAmount" name="SaleOfEquityAggregatePublicOfferingAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_RestrictedShareUnitAwardsAndPerformanceShareUnitAwardsMember" name="RestrictedShareUnitAwardsAndPerformanceShareUnitAwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_WarrantExercise" name="WarrantExercise" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_GeneralAndAdministrativeInternalExpense" name="GeneralAndAdministrativeInternalExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_AmendmentLoanAgreementAndRefinanceOfLoanMember" name="AmendmentLoanAgreementAndRefinanceOfLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_DebtInstrumentExtendedMaturityDate" name="DebtInstrumentExtendedMaturityDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_IncreaseDecreaseInDirectorsDeferredShareUnit-RelatedAccruals" name="IncreaseDecreaseInDirectorsDeferredShareUnit-RelatedAccruals" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_StockIssuedDuringPeriodValueWarrantsExercised" name="StockIssuedDuringPeriodValueWarrantsExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_DebtInstrumentConvertibleConvertedIntoCommonShares" name="DebtInstrumentConvertibleConvertedIntoCommonShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_LongTermInvestmentsMember" name="LongTermInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_MultipleVotingMember" name="MultipleVotingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_LeaseLiabilitiesArisingFromObtainingRight-Of-UseAssets" name="LeaseLiabilitiesArisingFromObtainingRight-Of-UseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_PaymentOfDeferredFinancingFeesRelatedToAtTheMarket" name="PaymentOfDeferredFinancingFeesRelatedToAtTheMarket" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_AmortizationOfDeferredFinancingCosts" name="AmortizationOfDeferredFinancingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_TwoThousandTwentyFiveEquityIncentivePlanMember" name="TwoThousandTwentyFiveEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_FirstTrancheTermLoanMember" name="FirstTrancheTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_CovenantShallBeWaivedDuringMarketCapitalizationExceeds" name="CovenantShallBeWaivedDuringMarketCapitalizationExceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_WeightedAverageNumberOfDilutedCommonSharesOutstanding" name="WeightedAverageNumberOfDilutedCommonSharesOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_WeightedAverageNumberOfPreFundedWarrantsOutstandingBasic" name="WeightedAverageNumberOfPreFundedWarrantsOutstandingBasic" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" name="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_TransactionCosts" name="TransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_TwoThousandTwentyTwoAtTheMarketOfferingProgramMember" name="TwoThousandTwentyTwoAtTheMarketOfferingProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_WithholdingTaxesPayableOnOptionExercises" name="WithholdingTaxesPayableOnOptionExercises" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_TwoThousandTwentyTwoUsdFinancingWarrantLiabilityMember" name="TwoThousandTwentyTwoUsdFinancingWarrantLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_DirectorsDeferredShareUnitPlanMember" name="DirectorsDeferredShareUnitPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_DebtRepaymentsOfPrincipalRemainderOfFiscalYearBeforeUnamortizedDebtIssuanceCost" name="DebtRepaymentsOfPrincipalRemainderOfFiscalYearBeforeUnamortizedDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_BoughtDealFinancingMember" name="BoughtDealFinancingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachUnit" name="ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachUnit" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_OtherLiabilitiesLongTerm" name="OtherLiabilitiesLongTerm" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_InducementEquityAwardsMember" name="InducementEquityAwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_SubordinateVotingMember" name="SubordinateVotingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsAmortizedCost" name="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsAmortizedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_WarrantsExpired" name="WarrantsExpired" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_UnderwrittenOfferingExcludingDiscountsAndCommissionsMember" name="UnderwrittenOfferingExcludingDiscountsAndCommissionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_DebtRepaymentsOfPrincipalInYearTwoBeforeUnamortizedDebtIssuanceCost" name="DebtRepaymentsOfPrincipalInYearTwoBeforeUnamortizedDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_K2HealthventuresLlcMember" name="K2HealthventuresLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AmendmentTermLoansMember" name="AmendmentTermLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_TermLoanMember" name="TermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_SaleOfEquityRemainingOfferingAmount" name="SaleOfEquityRemainingOfferingAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_WarrantsPolicyTextBlock" name="WarrantsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_FinancingWarrantsLiability" name="FinancingWarrantsLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_IndicationOfImpairmentOfGoodwillAndLongLivedAssets" name="IndicationOfImpairmentOfGoodwillAndLongLivedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_CompensationWarrantsMember" name="CompensationWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_WeightedAverageNumberOfCommonSharesOutstandingBasic" name="WeightedAverageNumberOfCommonSharesOutstandingBasic" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_StockIssuedDuringPeriodSharesConversionOfTermLoanPrincipal" name="StockIssuedDuringPeriodSharesConversionOfTermLoanPrincipal" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_IssuanceOfCommonSharesUponConversionOfTermLoanPrincipal" name="IssuanceOfCommonSharesUponConversionOfTermLoanPrincipal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_DebtRepaymentsOfPrincipalInYearThreeBeforeUnamortizedDebtIssuanceCosts" name="DebtRepaymentsOfPrincipalInYearThreeBeforeUnamortizedDebtIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue" name="AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_TwoThousandTwentySixInducementPlanMember" name="TwoThousandTwentySixInducementPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_UnderwrittenOfferingMember" name="UnderwrittenOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_PercentageOfIncreaseOrDecreaseOfOwnershipByPreFundedWarrantsHolder" name="PercentageOfIncreaseOrDecreaseOfOwnershipByPreFundedWarrantsHolder" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_WeightedAverageFairValueOfSharesPurchasedUponExerciseOfWarrants" name="WeightedAverageFairValueOfSharesPurchasedUponExerciseOfWarrants" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_StockIssuedDuringPeriodSharesUponSettlementOfRestrictedStockUnitAwards" name="StockIssuedDuringPeriodSharesUponSettlementOfRestrictedStockUnitAwards" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_StockIssuedDuringPeriodValueConversionOfTermLoanPrincipal" name="StockIssuedDuringPeriodValueConversionOfTermLoanPrincipal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_NatureOfOperationsAbstract" name="NatureOfOperationsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AggregateNumberOfCommonSharesOwnedByHolderPercentage" name="AggregateNumberOfCommonSharesOwnedByHolderPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_SubsequentTrancheTermLoanMember" name="SubsequentTrancheTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AggregateInducementAwardsOutstanding" name="AggregateInducementAwardsOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_OptionsIssuedAndOutstandingUnderStockOptionPlanMember" name="OptionsIssuedAndOutstandingUnderStockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ResearchAndDevelopmentExternalExpense" name="ResearchAndDevelopmentExternalExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_AdditionalTrancheTermLoanMember" name="AdditionalTrancheTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ProceedsFromOfferingsAndPrivatePlacement" name="ProceedsFromOfferingsAndPrivatePlacement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_ShareBasedPaymentArrangementDirectorsDeferredShareUnitPlanActivityTableTextBlock" name="ShareBasedPaymentArrangementDirectorsDeferredShareUnitPlanActivityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_RestructuredAgreementMember" name="RestructuredAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_CadFinancingAndCompensationWarrantsMember" name="CadFinancingAndCompensationWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_ScheduleOfWarrantLiabilityTableTextBlock" name="ScheduleOfWarrantLiabilityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_SummaryOfSharesReservedForIssuanceTableTextBlock" name="SummaryOfSharesReservedForIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_SharesAvailableForGrantUnderStockOptionPlanMember" name="SharesAvailableForGrantUnderStockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_MindMedStockOptionPlanMember" name="MindMedStockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsAmortizedCost" name="AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsAmortizedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_GeneralAndAdministrativeExternalExpense" name="GeneralAndAdministrativeExternalExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_SaleOfStockNumberOfAdditionalSharesIssuedInTransaction" name="SaleOfStockNumberOfAdditionalSharesIssuedInTransaction" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="dftx_FinancingWarrantsMember" name="FinancingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_DirectorsDeferredShareUnitsLiabilityMember" name="DirectorsDeferredShareUnitsLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_CommonShareAndWarrantPublicOfferingMember" name="CommonShareAndWarrantPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_EquityOfferingCostsInPrepaidsAndOtherCurrentAssetsNet" name="EquityOfferingCostsInPrepaidsAndOtherCurrentAssetsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="dftx_ExerciseOfWarrantShares" name="ExerciseOfWarrantShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="dftx_ResearchAndDevelopmentInternalExpense" name="ResearchAndDevelopmentInternalExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="dftx_UnderwrittenPublicOfferingMember" name="UnderwrittenPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="dftx_USDFinancingWarrantsNotIncludedMember" name="USDFinancingWarrantsNotIncludedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
