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  <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_OperatingExpensesBeforeGainLossOnSaleOfAssets" abstract="false" name="OperatingExpensesBeforeGainLossOnSaleOfAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_CashPayments2022Member" abstract="true" name="CashPayments2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_VestingOfRestrictedStockAwards" abstract="false" name="VestingOfRestrictedStockAwards" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="lnth_FinancialAssuranceInFormOfSuretyBond" abstract="false" name="FinancialAssuranceInFormOfSuretyBond" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_AccruedFreightCostsCurrent" abstract="false" name="AccruedFreightCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" abstract="false" name="LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_BedfordMassachusettsMember" abstract="true" name="BedfordMassachusettsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_AssetAcquisitionRoyaltyPercentage" abstract="false" name="AssetAcquisitionRoyaltyPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="lnth_MachineryEquipmentAndFixturesMember" abstract="true" name="MachineryEquipmentAndFixturesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_LeaseLiability" abstract="false" name="LeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_RadiopharmaceuticalOncologyMember" abstract="true" name="RadiopharmaceuticalOncologyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
</xs:schema>
