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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_FirstTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">First tranche july ordinary course placement agent warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_FirstTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">First Tranche July Ordinary Course Placement Agent Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegulatoryAgencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Agency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllOtherCorporateBondsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Corporate Bonds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllOtherCorporateBondsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Corporate bonds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivable Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="lgvn_PlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Placement Agent Warrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Placement agent warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Placement Agent Warrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Placement Agent Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Debt, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net proceeds (in Dollars)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril102029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On April 10, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril102029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On April 10, 2029.</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_RevenueFromContractWithCustomerPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfDecreaseInRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Decrease In Royalty</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfDecreaseInRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of decrease in royalty.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfDecreaseInRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of decrease in royalty</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Warrant [Member]</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="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders&#8217; equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrant Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreFundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrant Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate gross (in Dollars)</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 Events [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Accrued Expenses And Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase decrease in accrued expenses and other current liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisition of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOnePIPEOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty One PIPE Offering Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOnePIPEOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty One PIPEOffering Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOnePIPEOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2021 private placement offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOnePIPEOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2021 PIPE Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesRestrictedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Securities, Restricted [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoteWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Note Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoteWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Warrant Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentOtherAccumulatedDepreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Other, Accumulated Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentOtherAccumulatedDepreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less accumulated depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentOtherAccumulatedDepreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Less accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ExcessStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Excess Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ExcessStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unregistered shares (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Major Components of Property and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromSaleOfInterestInPriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Sale Of Interest In Priority Review Voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromSaleOfInterestInPriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from sale of interest in priority review voucher.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromSaleOfInterestInPriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of interest in 50% of PRV value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromSaleOfInterestInPriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from sale of interest of priority review voucher</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">Finite-Lived Intangible Asset, 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">Useful Lives</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 estimated useful life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesCWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series CWarrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesCWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series C warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract Manufacturing Revenue Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract Manufacturing Revenue Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract manufacturing revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contract manufacturing revenue [Member]</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 Stock Options, Options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Granted options to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets and Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease asset and lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property and Equipment, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfExtensionFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Extension Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfExtensionFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of extension fee.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfExtensionFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of extension fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature Of Business, Basis of Presentation, And Liquidity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nature of business, basis of presentation, and liquidity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nature of Business, Basis of Presentation, and Liquidity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_CommonWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Warrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_CommonWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_CommonWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Warrants Member</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/terseLabel">Basic net loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WeightedAveragePricePerShareToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average price per share to be achieved for second closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WeightedAveragePricePerShareToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Price Per Share To Be Achieved For Second Closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WeightedAveragePricePerShareToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average price per share to be achieved for second closing.</link:label>
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          <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 Stock Options, Outstanding at Beginning</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">Stock option issued and outstanding (in Shares)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Options to purchase common stock</link:label>
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          <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="lgvn_UnderwritersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwriters Member</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyRegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">July registered direct offering.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnOctober112028Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On October 11, 2028.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockOptionAwardFourYearVestingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock option award four year vesting period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockOptionAwardFourYearVestingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Option Award Four Year Vesting Period [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockOptionAwardFourYearVestingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Option Award Four Year Vesting Period [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred Stock</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">Purchase 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/label">Sale of Stock, Price Per Share</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">Equity Incentive Plan</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">Nature of Business, Basis of Presentation, and Liquidity [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfInterestSold_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of interest sold.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AnnualNetSalesPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Annual Net Sales Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AnnualNetSalesPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Annual net sales percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class A</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Class A Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class A Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability</link:label>
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          <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="lgvn_JulyPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">July Private Placement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">July Private Placement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyPrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">July Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRighstDateFromWhichWarrantsOrRightsExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Date from which Warrants or Rights Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRighstDateFromWhichWarrantsOrRightsExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants or rights exercisable date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant purchase shares</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">Net Cash Provided by (Used in) Operating Activities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash payment</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_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">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/terseLabel">Common Stock</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/verboseLabel">Common Stock [Member]</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, Options granted</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>
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          <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_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Per Share [Abstract]</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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnAugust112027OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On August 11, 2027 One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnAugust112027OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On August 11, 2027 One.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ClinicalTrialRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Clinical Trial Revenue Member</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SecretomeTherapeuticsIncorporatedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Secretome Therapeutics, Incorporated.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gross Profit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gross profit</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_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="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Change 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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Adjustment of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of warrants (in Dollars)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedInvestmentIncomeReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Investment Income Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedInvestmentIncomeReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued interest receivable related to money market funds</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/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">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerminationDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement termination description.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerminationDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement Termination Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerminationDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreement termination description</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 (in Dollars 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/verboseLabel">Price per share (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from warrants exercised, net of issuance cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net proceeds from issuance of warrants</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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options granted maximum term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfRevenueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Revenue Abstract</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_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_IncreaseDecreaseInOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnAugust112027Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On August 11, 2027 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnAugust112027Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On August 11, 2027.</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">Stock 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/verboseLabel">Number of Stock Options, 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">Class A common stock issued for warrants exercised (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Number of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options unvested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteSubscriptionsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note, Subscriptions Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteSubscriptionsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Stock subscription receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money Market Funds</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">Accrued Liabilities, Current, Total</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_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_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="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested shares (in Shares)</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">Outstanding (unvested) at December 31, 2025</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">Outstanding (unvested) at March 31, 2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly202026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On July 20, 2026 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly202026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On July 20, 2026.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Shares Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Shares Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Converted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee tax liabilities shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other General and Administrative Expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">UM License [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A common stock issued for warrants exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Option [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Option [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale and Maturity of Marketable Securities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ExerciseOfRemainingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of shares exercised.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOneIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty One Incentive Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOneIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty One Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TwoThousandTwentyOneIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2021 Incentive Plan</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="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="lgvn_PlacementAgentWarrants1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Placement agent warrants one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PlacementAgentWarrants1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Placement Agent Warrants 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PlacementAgentWarrants1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Placement Agent Warrants June 2024 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfIssuedAndOutstandingOptionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Issued And Outstanding Options Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Axis]</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 Other Comprehensive (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, carrying value</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 [Member]</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="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_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization expense related to intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class B Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class B Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class B common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Class B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril182029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On April 18, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril182029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On April 18, 2029.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Future Amortization Expense for Intangible Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Finite-Lived Intangible Assets [Member]</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_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">Net unrealized gains and losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfPriorityReviewVoucherInterestSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Priority Review Voucher Interest Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfPriorityReviewVoucherInterestSold_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of priority review voucher interest sold.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfPriorityReviewVoucherInterestSold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of priority review voucher interest sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockOtherSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Other Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockOtherSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate 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/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 (in 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 (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Receivable, after Allowance for Credit Loss, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accounts Receivable</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 9)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInNonoperatingLawsuitLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease in Nonoperating Lawsuit Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInNonoperatingLawsuitLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in nonoperating lawsuit liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_IncreaseDecreaseInNonoperatingLawsuitLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nonoperating lawsuit liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based compensation (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Present value of operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromIssuanceOfCommonStockAndPreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Issuance Of Common Stock And Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromIssuanceOfCommonStockAndPreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from issuance of common stock and preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsFromIssuanceOfCommonStockAndPreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from the issuance of common and preferred stock, net of issuance cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriosSharesClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class A common stock, held for taxes on RSUs vested shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriosSharesClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Perios Shares Class ACommon Stock Held For Taxes On RSUs Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriosSharesClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A common stock, held for taxes on RSUs vested (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfRoyaltyFromTheFirstCommercialSalePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Royalty From The First Commercial Sale Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfRoyaltyFromTheFirstCommercialSalePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of royalty from the first commercial sale period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentOfRoyaltyFromTheFirstCommercialSalePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of royalty from the first commercial sale in period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Noncurrent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term liabilities:</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/totalLabel">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ClassACommonStockWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class ACommon Stock Warrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ClassACommonStockWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A common stock warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_LeasesDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases (Details) [Table]</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">Basic weighted average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentPerWarrant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Per Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentPerWarrant_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment per warrant.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentPerWarrant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment per warrant (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_UMAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">UMAgreements Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_UMAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">UM Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Expense Information Used by CODM, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting, Expense Information Used by CODM, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MinimumTradingVolumeSharesToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Trading Volume Shares To Be Achieved For Second Closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MinimumTradingVolumeSharesToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum trading volume shares to be achieved for second closing.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MinimumTradingVolumeSharesToBeAchievedForSecondClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum trading volume shares to be achieved for second closing</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_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="lgvn_WarrantsExpiringOnMarch112031Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On March 11, 2031 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnMarch112031Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On March 11, 2031.</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 stockholders&#8217; equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value (in Dollars per share)</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="lgvn_Rule10b51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rule10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_Rule10b51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rule 10b51 ArrModified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026 (remaining nine months)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Approach and Technique [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesAPreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesAPreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A Preferred Stock [Member]</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_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasehold Improvements [Member]</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_AccruedIncomeReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued income [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On June 18, 2026 One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On June 18, 2026 One.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract Manufacturing Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract manufacturing [Member]</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_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">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="lgvn_firstPhase3ClinicalTrialMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">first Phase3 Clinical Trial Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_firstPhase3ClinicalTrialMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">first Phase 3 Clinical Trial [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Other Segment Item, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other segment items</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_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivable [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesFromStockholderMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivables from Stockholder [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesFromStockholderMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subscription Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment, Long-Lived Asset, Held-for-Use</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of long-lived assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Impairment, Long-Lived Asset, Held-for-Use, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Description and Basis of Presentation [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nature of Business, Basis of Presentation, Going Concern and Liquidity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Award amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-Based Payment Arrangement, Expensed and Capitalized, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrecognized equity based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TermsOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Terms of agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TermsOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Terms Of Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TermsOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreement term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PartnersCapitalAccountUnitsSoldInPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Partners' Capital Account, Units, Sold in Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PartnersCapitalAccountUnitsSoldInPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Public offering shares</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/terseLabel">Number of warrants 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/verboseLabel">Warrant shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockSharesIssuedNetOfSharesForTaxWithholdings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock, Shares Issued Net of Shares for Tax Withholdings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockSharesIssuedNetOfSharesForTaxWithholdings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSUs vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Future Minimum Payments Under the Operating Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deemed dividend to common stockholders (in Dollars)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdateExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Extensible Enumeration]</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="lgvn_StockholdersEquityDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders&#8217; Equity (Details) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockIssuedForRSUsVestedInShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A common stock, issued for RSUs vested (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockIssuedForRSUsVestedInShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Class A Common Stock Issued For RSUs Vested in Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockIssuedForRSUsVestedInShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class A common stock, issued for RSUs vested shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOrdinaryCoursePlacementAgentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">July Ordinary Course Placement Agent Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOrdinaryCoursePlacementAgentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">July Ordinary Course Placement Agent Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOrdinaryCoursePlacementAgentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">July Ordinary Course Placement Agent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegulatoryAgencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Agency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsIssuedInAugustTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Issued in August Two Thousand Twenty Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsIssuedInAugustTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants issued in August 2025.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsIssuedInAugustTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants Issued in August 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options vested (based on ratable vesting)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Impairment Long Lived Asset Held For Use Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment Long Lived Asset Held For Use Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents at end of the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents at beginning of the period</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="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">Warrants exercise price per share (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercise price (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Income and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income and (expenses)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title and Position [Axis]</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_DefinedContributionPlanCostRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanCostRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Company contributed amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_EquityBasedCompensationDetailsScheduleofStockOptionActivityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Stock Option Activity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfStockOptionActivityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Stock Option Activity Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_RockSofferMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rock soffer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_RockSofferMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rock Soffer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_RockSofferMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rock Soffer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">RSUs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation and Employee Benefit Plans [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefits Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TemporaryReductionInEquityCompensationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Reduction In Equity Compensation Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TemporaryReductionInEquityCompensationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary reduction in equity compensation percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_TemporaryReductionInEquityCompensationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary reduction in compensation, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueConsensusPricingModelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Technique, Consensus Pricing Model [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationTechniqueConsensusPricingModelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Black-Scholes pricing model [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseDiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_BiologicsLicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Biologics License Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_BiologicsLicenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Biologics license [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_December2023OfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">December2023 Offering Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_December2023OfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">December 2023 registered direct offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ReverseStockSplitPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of Reverse Stock Split.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ReverseStockSplitPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reverse Stock Split Policy Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ReverseStockSplitPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reverse Stock Split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of RSU Activity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfDilutedNetLossPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Diluted Net Loss Per Share Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingLeaseRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract manufacturing lease revenue.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingLeaseRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract Manufacturing Lease Revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingLeaseRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract manufacturing lease revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ContractManufacturingLeaseRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contract manufacturing lease revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost</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">Diluted weighted average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Diluted, Total</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="lgvn_SeriesDWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series DWarrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesDWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series D Warrants [Member]</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="lgvn_PerformanceBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Performance Bonus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PerformanceBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Performance bonus.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PerformanceBonus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance bonus</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_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_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expenditures amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_VestingOfRSUsAndPSUsIntoClassACommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of vesting of RSU and PSUs into class A common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_VestingOfRSUsAndPSUsIntoClassACommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vesting Of RSUs And PSUs Into Class ACommon Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_VestingOfRSUsAndPSUsIntoClassACommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of RSUs and PSUs into Class A common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ChiefScienceOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chief Science Officer Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ChiefScienceOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Chief Science Officer [Member]</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 expenses and other current assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">RSU expired/forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Percentage of Outstanding Stock Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesCWarrantsAndSeriesDWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series C Warrants and Series D warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesCWarrantsAndSeriesDWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series C Warrants and Series D warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfMarketableSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Marketable Securities Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement term.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreement term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Benchmark [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalAndContractServicesExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Professional and Contract Services Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalAndContractServicesExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Professional and Contract Services Expense</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_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">G&amp;A costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AtTheMarketATMMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">At The Market (ATM) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AtTheMarketATMMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">At the market (ATM).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AtTheMarketATMMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">At-The-Market</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AtTheMarketATMMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">At The Market (ATM) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_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="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase price per preferred share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Stock Options, Options expired/forfeited</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="lgvn_InvestorWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investor warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_InvestorWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investor warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasedAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeferredOfferingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Offering Costs Policy Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeferredOfferingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Offering Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_EquityBasedCompensationDetailsScheduleofRSUActivityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity-Based Compensation (Details) - Schedule of RSU Activity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreferredStockAuthorizedShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock Authorized Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreferredStockAuthorizedShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Preferred stock authorized shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PreferredStockAuthorizedShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, authorized shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Useful Lives</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">New Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Future Minimum Payments Under the Operating Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of RSU Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NonRule10b51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Rule10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NonRule10b51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-Rule 10b51 ArrModified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A non-voting convertible preferred stock issued in private placement (in Shares)</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">Options 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/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_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AprilTwoThousandTwentyFourPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">April Two Thousand Twenty Four Public Offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AprilTwoThousandTwentyFourPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">April Two Thousand Twenty Four Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AprilTwoThousandTwentyFourPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">April 2024 Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reportable Segment, Aggregation before Other Operating Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reportable Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current portion of operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationDepletionAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Depletion and Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationDepletionAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationDepletionAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Depletion and Amortization, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature Of Business, Basis of Presentation, and Liquidity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nature of business, basis of presentation, and liquidity.</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="lgvn_UnderwritersWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwriters Warrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_UnderwritersWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwriters Warrants [Member]</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/totalLabel">Research and Development Expense, 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/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/terseLabel">Research and development</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/verboseLabel">R&amp;D costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cost of Revenue, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivableTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivable [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NationalInstitutesOfHealthGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">National Institutes Of Health Grant Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NationalInstitutesOfHealthGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">National Institutes of Health &#8211; Grant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NationalInstitutesOfHealthGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">NIH - grant [Member]</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="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">Class A common stock issued in private placement/At-The-Market offering, net of 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_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">Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts and Financing Receivables [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsToBeReceivedFromThePotentialFutureSale_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds to Be Received From the Potential Future Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsToBeReceivedFromThePotentialFutureSale_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds to be received from the potential future sale.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ProceedsToBeReceivedFromThePotentialFutureSale_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Major Components of Intangible Assets [Line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Computer Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Computer Equipment [Member]</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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneAchievementPeriodOnApprovalOfLastCommercializedProduct_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Achievement Period On Approval Of Last Commercialized Product</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneAchievementPeriodOnApprovalOfLastCommercializedProduct_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone acievement period on approval of the last commercialized product</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneAchievementPeriodOnApprovalOfLastCommercializedProduct_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone achievement period on approval of last commercialized product.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfAggregateNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of aggregate number of shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfAggregateNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Aggregate Number Of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PercentageOfAggregateNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of aggregate number of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease cost</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_WarrantsAndRightsOutstandingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant 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/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">Dividend yield</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasicLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Diluted Net Loss per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Net (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_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_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease - cash flow</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate</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 expenses 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="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Investing Activities [Abstract]</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_CompensationAndRetirementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefits Plan [Abstract]</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_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_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentExpirationOrDueDateDayMonthAndYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Expiration or Due Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentExpirationOrDueDateDayMonthAndYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expire date</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 Measurement</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 [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from License Fees Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune222029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On June 22, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune222029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On June 22, 2029.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DerivativeInstrumentRiskAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Derivative Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Incentive Plan [Abstract]</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_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of contract manufacturing revenue</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">Net Cash Provided by (Used in) Investing Activities</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Options expired/forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Weighted Average Exercise Price, Options expired/forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money market funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MaximumSaleOfAggregateMarketValueOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Sale Of Aggregate Market Value Of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MaximumSaleOfAggregateMarketValueOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum sale of aggregate market value of shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MaximumSaleOfAggregateMarketValueOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum sale of aggregate market value of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PatentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Patents [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PatentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Patent costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026 (remaining nine months)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other 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/verboseLabel">Other long-term liabilities</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">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_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Major Components of Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/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 at ending</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 at Beginning</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/terseLabel">Exercise price (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On June 18, 2026 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On June 18, 2026.</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="lgvn_NetSalesOfSubLicensees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net sales of sub licensees percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NetSalesOfSubLicensees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net sales of sub licensees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_NetSalesOfSubLicensees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Sales Of Sub Licensees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly202026OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On July 20, 2026 One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly202026OneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On July 20, 2026 One.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_EquityBasedCompensationDetailsScheduleofStockOptionActivityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity-Based Compensation (Details) - Schedule of Stock Option Activity [Table]</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="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Finite-Lived [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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/terseLabel">Schedule of Major Components 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/label">Net Cash Provided by (Used in) Financing Activities [Abstract]</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_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="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="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneOfTriggeringPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of milestone of triggering payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneOfTriggeringPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Of Triggering Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MilestoneOfTriggeringPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: Interest (5% discount rate)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: Interest (5% discount rate)</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="lgvn_USFoodAndAdministrationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">U. S. Food And Administration [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_USFoodAndAdministrationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">U. S. food and administration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly172026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On July 17, 2026 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJuly172026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On July 17, 2026.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other income, net</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_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="lgvn_ScheduleOfAccountsAndGrantsReceivableAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Accounts And Grants Receivable Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Public offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeemedDividendWarrantInducementOffers_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deemed dividend &#8211; warrant inducement offers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeemedDividendWarrantInducementOffers_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deemed dividend &#8211; warrant inducement offers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeemedDividendWarrantInducementOffers_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the amount of deemed dividend warrant inducement offers.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_DeemedDividendWarrantInducementOffers_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deemed Dividend Warrant Inducement Offers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Depletion and Amortization, Nonproduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfMajorComponentsOfIntangibleAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Major Components Of Intangible Assets Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockVotingRights_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Voting Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockVotingRights_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock voting rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Comprehensive Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SupplyAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Supply agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SupplyAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supply Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SupplyAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supply Agreement [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/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</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="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, Options 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">Exercise price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated Amortization</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 stock value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Other Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments to UM</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsOrRightsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsOrRightsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants or Rights [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsOrRightsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants or rights.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of Long-Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Marketable Securities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable Securities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Issued and Outstanding Options [Line Items]</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_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Future Amortization Expense for Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentsForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments for taxes on RSUs vested.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentsForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments For Taxes On RSUs Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PaymentsForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments for taxes on RSUs vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class A common stock, held for taxes on RSUs vested.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Class ACommon Stock Held For Taxes On RSUs Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_StockIssuedDuringPeriodClassACommonStockHeldForTaxesOnRSUsVested_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A common stock, held for taxes on RSUs vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_OperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating segment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_OperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_OperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesAAndSeriesBWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series AAnd Series BWarrants Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SeriesAAndSeriesBWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A and Series B Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_LiabilityRelatedToSaleOfFuturePriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability Related to Sale of Future Priority Review Voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_LiabilityRelatedToSaleOfFuturePriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Liability related to sale of future priority review voucher.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_LiabilityRelatedToSaleOfFuturePriorityReviewVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability related to the sale of future PRV proceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PhantomShareUnitsPSUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Phantom Share Units (PSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PhantomShareUnitsPSUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PSUs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsNotesAndLoansReceivableLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accounts and Grants Receivable [Line Items]</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">Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_CustomerOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer One.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_CustomerOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOfferingPlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">July Offering Placement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOfferingPlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">July Offering Placement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JulyOfferingPlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">July Offering Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_ScheduleOfMajorComponentsOfPropertyAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Major Components Of Property And Equipment Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueArrangementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Revenue [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril82029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On April 8, 2029 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnApril82029Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On April 8, 2029.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of stock issued</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_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_October2023RegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">October2023 Registered Direct Offering Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_October2023RegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">October 2023 registered direct offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Costs and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less:</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">Equity-Based Compensation [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">Equity Incentive Plan [Line Items]</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="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">Concentrations of Credit Risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JunePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">June Placement Agent Warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JunePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">June Placement Agent Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_JunePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">June Placement Agent Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_MarketableSecuritiesDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities (Details) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisition of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSU granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PersonnelCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Personnel costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PersonnelCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Personnel Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_PersonnelCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Personnel costs</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_FiniteLivedIntangibleAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SecondTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Second tranche July ordinary course placement agent warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SecondTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Second Tranche July Ordinary Course Placement Agent Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_SecondTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Second Tranche July Ordinary Course Placement Agent Warrants [Member]</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 options 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="lgvn_AccountsReceivableFromCustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable From Customers Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_AccountsReceivableFromCustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable from customers [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized equity-based compensation term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndMarketableSecuritiesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, and Marketable Securities [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndMarketableSecuritiesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money Market Funds and Fair Value Measurement</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">Issued and sold an aggregate shares</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_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">Class A common stock issued in private placement/At-The-Market offering, net of issuance cost (in 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/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">RSUs 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/terseLabel">Diluted net loss per share</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="lgvn_ScheduleOfRsuActivityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Rsu Activity Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Significant Expense Categories Provided to CODM</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title and Position [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_OtherComprehensiveLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Loss Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_OtherComprehensiveLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive gains:</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="us-gaap_LicensingAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Licensing Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LicensingAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026TwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiring On June 18, 2026 Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="lgvn_WarrantsExpiringOnJune182026TwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Expiring On June 18, 2026 Two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average remaining lease term (years)</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/label">Stockholders' Equity Note, Stock Split, Conversion Ratio</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">Reverse stock split ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantExercisePriceIncrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant, Exercise Price, Increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantExercisePriceIncrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise price (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsFinitelived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of Intangible Assets, Finite-Lived</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/label">Impairment of Intangible Assets, Finite-Lived</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/verboseLabel">Finite lived intangible assets, impairments or write-offs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_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_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based compensation</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">Class A common stock issued in public offering, issuance costs</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares"/>
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        <link:calculationLink xlink:type="extended" xlink:role="http://LongeveronInc.com/20260331/taxonomy/role/DisclosureSegmentInformationScheduleOfSignificantExpenseCategoriesProvidedToCodmDetails">
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_CostOfRevenue" order="1" weight="-1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_ResearchAndDevelopmentExpense" order="2" weight="-1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_GeneralAndAdministrativeExpense" order="3" weight="-1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="lgvn_PersonnelCosts" order="4" weight="-1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_SegmentReportingOtherItemAmount" order="5" weight="-1" use="optional"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="us-gaap_CostOfRevenue"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="us-gaap_GeneralAndAdministrativeExpense"/>
          <link:loc xlink:type="locator" xlink:href="lgvn-20260331.xsd#lgvn_PersonnelCosts" xlink:label="lgvn_PersonnelCosts"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingOtherItemAmount" xlink:label="us-gaap_SegmentReportingOtherItemAmount"/>
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    </xsd:appinfo>
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  <xsd:element id="lgvn_UnderwritersMember" name="UnderwritersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SeriesANon-VotingConvertiblePreferredStockMember" name="SeriesANon-VotingConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsIssuedInAugustTwoThousandTwentyFiveMember" name="WarrantsIssuedInAugustTwoThousandTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_JulyPrivatePlacementMember" name="JulyPrivatePlacementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" name="ImpairmentLongLivedAssetHeldForUseStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_WarrantsExpiringOnApril182029Member" name="WarrantsExpiringOnApril182029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfRevenueAbstract" name="ScheduleOfRevenueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_firstPhase3ClinicalTrialMember" name="firstPhase3ClinicalTrialMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJune222029Member" name="WarrantsExpiringOnJune222029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" name="IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_PercentageOfDecreaseInRoyalty" name="PercentageOfDecreaseInRoyalty" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_TermsOfAgreement" name="TermsOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_PaymentsForTaxesOnRSUsVested" name="PaymentsForTaxesOnRSUsVested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_StockIssuedDuringPeriodClassACommonStockIssuedForRSUsVestedInShares" name="StockIssuedDuringPeriodClassACommonStockIssuedForRSUsVestedInShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_December2023OfferingMember" name="December2023OfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfDilutedNetLossPerShareAbstract" name="ScheduleOfDilutedNetLossPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_LiabilityRelatedToSaleOfFuturePriorityReviewVoucher" name="LiabilityRelatedToSaleOfFuturePriorityReviewVoucher" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_ShareBasedCompensationArrangementByShareBasedPaymentStockOptionExpirationTerm" name="ShareBasedCompensationArrangementByShareBasedPaymentStockOptionExpirationTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_EquityBasedCompensationDetailsScheduleofStockOptionActivityLineItems" name="EquityBasedCompensationDetailsScheduleofStockOptionActivityLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ProceedsFromIssuanceOfCommonStockAndPreferredStock" name="ProceedsFromIssuanceOfCommonStockAndPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_ScheduleOfRsuActivityAbstract" name="ScheduleOfRsuActivityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_TwoThousandTwentyOnePIPEOfferingMember" name="TwoThousandTwentyOnePIPEOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_OperatingSegmentMember" name="OperatingSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PlacementAgentWarrants1Member" name="PlacementAgentWarrants1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PaymentOfExtensionFee" name="PaymentOfExtensionFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_JulyRegisteredDirectOfferingMember" name="JulyRegisteredDirectOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnAugust112027Member" name="WarrantsExpiringOnAugust112027Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityLineItems" name="NatureOfBusinessBasisOfPresentationAndLiquidityLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_AprilTwoThousandTwentyFourPublicOfferingMember" name="AprilTwoThousandTwentyFourPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsOrRightsPolicyTextBlock" name="WarrantsOrRightsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_ProceedsFromSaleOfInterestInPriorityReviewVoucher" name="ProceedsFromSaleOfInterestInPriorityReviewVoucher" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_MinimumTradingVolumeSharesToBeAchievedForSecondClosing" name="MinimumTradingVolumeSharesToBeAchievedForSecondClosing" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_UnderwritersWarrantsMember" name="UnderwritersWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_JuneInducementWarrantsMember" name="JuneInducementWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PercentageOfAggregateNumberOfShares" name="PercentageOfAggregateNumberOfShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_NatureOfBusinessBasisOfPresentationAndLiquidityTable" name="NatureOfBusinessBasisOfPresentationAndLiquidityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_DeemedDividendWarrantInducementOffers" name="DeemedDividendWarrantInducementOffers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_BiologicsLicenseMember" name="BiologicsLicenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SeriesDWarrantsMember" name="SeriesDWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_InvestorWarrantsMember" name="InvestorWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJune182026OneMember" name="WarrantsExpiringOnJune182026OneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnMarch112031Member" name="WarrantsExpiringOnMarch112031Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SupplyAgreementMember" name="SupplyAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_InterestEarnedOnMarketableSecurities" name="InterestEarnedOnMarketableSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_StockIssuedDuringPeriosSharesClassACommonStockHeldForTaxesOnRSUsVested" name="StockIssuedDuringPeriosSharesClassACommonStockHeldForTaxesOnRSUsVested" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_JunePlacementAgentWarrantsMember" name="JunePlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJuly242026Member" name="WarrantsExpiringOnJuly242026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfMajorComponentsOfIntangibleAssetsAbstract" name="ScheduleOfMajorComponentsOfIntangibleAssetsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_StockholdersEquityDetailsTable" name="StockholdersEquityDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PercentageOfInterestSold" name="PercentageOfInterestSold" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_ContractManufacturingRevenueMember" name="ContractManufacturingRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfIssuedAndOutstandingOptionsAbstract" name="ScheduleOfIssuedAndOutstandingOptionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_AnnualNetSalesPercentage" name="AnnualNetSalesPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_CommonWarrantsMember" name="CommonWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnFebruary122026Member" name="WarrantsExpiringOnFebruary122026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_AgreementTerminationDescription" name="AgreementTerminationDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_ContractManufacturingMember" name="ContractManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnApril182029OneMember" name="WarrantsExpiringOnApril182029OneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_MaximumSaleOfAggregateMarketValueOfShares" name="MaximumSaleOfAggregateMarketValueOfShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_SummaryofSignificantAccountingPoliciesDetailsTable" name="SummaryofSignificantAccountingPoliciesDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfMarketableSecuritiesAbstract" name="ScheduleOfMarketableSecuritiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_EquityBasedCompensationDetailsScheduleofIssuedandOutstandingOptionsTable" name="EquityBasedCompensationDetailsScheduleofIssuedandOutstandingOptionsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnApril82029Member" name="WarrantsExpiringOnApril82029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_FullyVestedOptionsToPurchaseSharesOfCommonStock" name="FullyVestedOptionsToPurchaseSharesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_USFoodAndAdministrationMember" name="USFoodAndAdministrationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ProceedsToBeReceivedFromThePotentialFutureSale" name="ProceedsToBeReceivedFromThePotentialFutureSale" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_AtTheMarketATMMember" name="AtTheMarketATMMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_LeasesDetailsTable" name="LeasesDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_EquityBasedCompensationDetailsScheduleofStockOptionActivityTable" name="EquityBasedCompensationDetailsScheduleofStockOptionActivityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJuly202026OneMember" name="WarrantsExpiringOnJuly202026OneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ClinicalTrialRevenueMember" name="ClinicalTrialRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_MilestoneFeesPayable" name="MilestoneFeesPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_PersonnelCosts" name="PersonnelCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_ExerciseOfRemainingShares" name="ExerciseOfRemainingShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_RockSofferMember" name="RockSofferMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ReverseStockSplitPolicyTextBlock" name="ReverseStockSplitPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_AccountsReceivableFromCustomersMember" name="AccountsReceivableFromCustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfStockOptionActivityAbstract" name="ScheduleOfStockOptionActivityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PlacementAgentWarrantsMember" name="PlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_DeferredOfferingCostsPolicyTextBlock" name="DeferredOfferingCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_MilestoneOfTriggeringPayments" name="MilestoneOfTriggeringPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_FirstTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember" name="FirstTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnAugust112027OneMember" name="WarrantsExpiringOnAugust112027OneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsToPurchase" name="WarrantsToPurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_OtherComprehensiveLossAbstract" name="OtherComprehensiveLossAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJune182026TwoMember" name="WarrantsExpiringOnJune182026TwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_CommitmentsandContingenciesDetailsTable" name="CommitmentsandContingenciesDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PercentageOfPriorityReviewVoucherInterestSold" name="PercentageOfPriorityReviewVoucherInterestSold" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_NetSalesOfSubLicensees" name="NetSalesOfSubLicensees" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_PreFundedWarrantMember" name="PreFundedWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PerformanceBonus" name="PerformanceBonus" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_SeriesCWarrantsAndSeriesDWarrantsMember" name="SeriesCWarrantsAndSeriesDWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PreferredStockAuthorizedShares" name="PreferredStockAuthorizedShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_VestingOfRSUsAndPSUsIntoClassACommonStock" name="VestingOfRSUsAndPSUsIntoClassACommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_IncreaseDecreaseInNonoperatingLawsuitLiability" name="IncreaseDecreaseInNonoperatingLawsuitLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="lgvn_JulyOrdinaryCoursePlacementAgentMember" name="JulyOrdinaryCoursePlacementAgentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WeightedAveragePricePerShareToBeAchievedForSecondClosing" name="WeightedAveragePricePerShareToBeAchievedForSecondClosing" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_Rule10b51ArrModifiedFlag" name="Rule10b51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_TwoThousandTwentyOneIncentivePlanMember" name="TwoThousandTwentyOneIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_CustomerOneMember" name="CustomerOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_October2023RegisteredDirectOfferingMember" name="October2023RegisteredDirectOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnDecember202028Member" name="WarrantsExpiringOnDecember202028Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SeriesCWarrantsMember" name="SeriesCWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfAccountsAndGrantsReceivableAbstract" name="ScheduleOfAccountsAndGrantsReceivableAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_EquityBasedCompensationDetailsScheduleofRSUActivityTable" name="EquityBasedCompensationDetailsScheduleofRSUActivityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJuly172026Member" name="WarrantsExpiringOnJuly172026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SecretomeTherapeuticsIncorporatedMember" name="SecretomeTherapeuticsIncorporatedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_PaymentOfRoyaltyFromTheFirstCommercialSalePeriod" name="PaymentOfRoyaltyFromTheFirstCommercialSalePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_NonRule10b51ArrModifiedFlag" name="NonRule10b51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_AgreementTerm" name="AgreementTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_StockIssuedDuringPeriodClassACommonStockHeldForTaxesOnRSUsVested" name="StockIssuedDuringPeriodClassACommonStockHeldForTaxesOnRSUsVested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="lgvn_PaymentPerWarrant" name="PaymentPerWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_SummaryofSignificantAccountingPoliciesDetailsLineItems" name="SummaryofSignificantAccountingPoliciesDetailsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnDecember12026Member" name="WarrantsExpiringOnDecember12026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SecondTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember" name="SecondTrancheJulyOrdinaryCoursePlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_MarketableSecuritiesDetailsTable" name="MarketableSecuritiesDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ChiefScienceOfficerMember" name="ChiefScienceOfficerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_MilestoneAchievementPeriodOnApprovalOfLastCommercializedProduct" name="MilestoneAchievementPeriodOnApprovalOfLastCommercializedProduct" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_ContractManufacturingLeaseRevenueMember" name="ContractManufacturingLeaseRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_NationalInstitutesOfHealthGrantMember" name="NationalInstitutesOfHealthGrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJune182026Member" name="WarrantsExpiringOnJune182026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnJuly202026Member" name="WarrantsExpiringOnJuly202026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnOctober112028Member" name="WarrantsExpiringOnOctober112028Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ClassACommonStockWarrantsMember" name="ClassACommonStockWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_TemporaryReductionInEquityCompensationPercentage" name="TemporaryReductionInEquityCompensationPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="lgvn_UMAgreementsMember" name="UMAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_ScheduleOfMajorComponentsOfPropertyAndEquipmentAbstract" name="ScheduleOfMajorComponentsOfPropertyAndEquipmentAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_StockOptionAwardFourYearVestingPeriodMember" name="StockOptionAwardFourYearVestingPeriodMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_SeriesAAndSeriesBWarrantsMember" name="SeriesAAndSeriesBWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_EquityBasedCompensationDetailsTable" name="EquityBasedCompensationDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_JulyOfferingPlacementMember" name="JulyOfferingPlacementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="lgvn_WarrantsExpiringOnApril102029Member" name="WarrantsExpiringOnApril102029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
