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  <xs:element id="lnth_EffectiveIncomeTaxRateReconciliationIncreaseInIndemnificationDeferredTaxAsset" abstract="false" name="EffectiveIncomeTaxRateReconciliationIncreaseInIndemnificationDeferredTaxAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_A2022FacilityCovenantsMember" abstract="true" name="A2022FacilityCovenantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_LicenseandRoyaltyRevenuesMember" abstract="true" name="LicenseandRoyaltyRevenuesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_ProgenicsMember" abstract="true" name="ProgenicsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_Amended10b51PlanMember" abstract="true" name="Amended10b51PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lnth_CurrentlyMarketedProductMember" abstract="true" name="CurrentlyMarketedProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_RightOfUseAssetObtainedInExchangeForLeaseLiabilityAbstract" abstract="true" name="RightOfUseAssetObtainedInExchangeForLeaseLiabilityAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="lnth_CashFlowLesseeAbstract" abstract="true" name="CashFlowLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="lnth_OtherPrecisionDiagnosticsMember" abstract="true" name="OtherPrecisionDiagnosticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_NetSalesTargetsForAzedraMember" abstract="true" name="NetSalesTargetsForAzedraMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_BusinessCombinationContingentLiabilityContingentValueRightConsideration" abstract="false" name="BusinessCombinationContingentLiabilityContingentValueRightConsideration" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_ContingentValueRightMember" abstract="true" name="ContingentValueRightMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_ContingentPaymentsUnderCompanysLicenseAgreements" abstract="false" name="ContingentPaymentsUnderCompanysLicenseAgreements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_DebtInstrumentCovenantComplianceNumberOfFinancialCovenants" abstract="false" name="DebtInstrumentCovenantComplianceNumberOfFinancialCovenants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="lnth_MeasurementInputProbabilityOfSuccessMember" abstract="true" name="MeasurementInputProbabilityOfSuccessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_RadiopharmaceuticalOncologyMember" abstract="true" name="RadiopharmaceuticalOncologyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_Q12024Member" abstract="true" name="Q12024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_PerspectiveTherapeuticsIncMember" abstract="true" name="PerspectiveTherapeuticsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lnth_ContingentConsiderationNetSalesTargetsMember" abstract="true" name="ContingentConsiderationNetSalesTargetsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_LeaseWeightedAverageRemainingLeaseTermAbstract" abstract="true" name="LeaseWeightedAverageRemainingLeaseTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
</xs:schema>
