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  <xs:element id="mlys_NoncashOrPartNoncashAcquisitionFundsReceivableFromStockOptionExercises" abstract="false" name="NoncashOrPartNoncashAcquisitionFundsReceivableFromStockOptionExercises" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_ScheduleOfCommonStockAuthorizedTableTextBlock" abstract="false" name="ScheduleOfCommonStockAuthorizedTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mlys_AccruedResearchAndDevelopmentCostsCurrent" abstract="false" name="AccruedResearchAndDevelopmentCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_TanabeMember" abstract="true" name="TanabeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsUpfrontFee" abstract="false" name="CollaborativeArrangementRightsAndObligationsUpfrontFee" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsDevelopmentalMaximumAggregateMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsDevelopmentalMaximumAggregateMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsCommercialSaleMaximumAggregateMilestoneOneTimePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsCommercialSaleMaximumAggregateMilestoneOneTimePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsAdditionalCommercialSaleMaximumAggregateMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsAdditionalCommercialSaleMaximumAggregateMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsFirstCommercialSaleMaximumAggregateMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsFirstCommercialSaleMaximumAggregateMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsSecondCommercialSaleMaximumAggregateMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsSecondCommercialSaleMaximumAggregateMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsRecognizedOneTimePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsRecognizedOneTimePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_CollaborativeArrangementRightsAndObligationsFirstCommercialSaleMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsFirstCommercialSaleMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_TheLoanAgreementMember" abstract="true" name="TheLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_DebtInstrumentTranchesAxis" abstract="true" name="DebtInstrumentTranchesAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="mlys_DebtInstrumentTranchesDomain" abstract="true" name="DebtInstrumentTranchesDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_TrancheALoanMember" abstract="true" name="TrancheALoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_TrancheBLoanMember" abstract="true" name="TrancheBLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_TrancheCLoanMember" abstract="true" name="TrancheCLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_TrancheDLoanMember" abstract="true" name="TrancheDLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_DebtInstrumentBasisFloor" abstract="false" name="DebtInstrumentBasisFloor" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mlys_DebtInstrumentFundingFeePercentage" abstract="false" name="DebtInstrumentFundingFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mlys_DebtInstrumentFundingFeePaid" abstract="false" name="DebtInstrumentFundingFeePaid" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_DebtInstrumentInstallmentsLoanRepaymentTerm" abstract="false" name="DebtInstrumentInstallmentsLoanRepaymentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mlys_DebtInstrumentFundingFeeFinalFeeAsAPercentageOfOriginalPrincipal" abstract="false" name="DebtInstrumentFundingFeeFinalFeeAsAPercentageOfOriginalPrincipal" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mlys_DebtInstrumentFundingFeeFinalLoanRepayment" abstract="false" name="DebtInstrumentFundingFeeFinalLoanRepayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_DebtInstrumentCovenantMinimumTrailingConsolidatedNetProductRevenuePeriod" abstract="false" name="DebtInstrumentCovenantMinimumTrailingConsolidatedNetProductRevenuePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mlys_EquityIncentivePlan2023Member" abstract="true" name="EquityIncentivePlan2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_EquityIncentivePlan2025Member" abstract="true" name="EquityIncentivePlan2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_PreFundedWarrantMember" abstract="true" name="PreFundedWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_PriorATMAgreementMember" abstract="true" name="PriorATMAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_SaleOfStockConsiderationReceivableOnTransaction" abstract="false" name="SaleOfStockConsiderationReceivableOnTransaction" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_SaleOfStockPricePerShareWeightedAveragePrice" abstract="false" name="SaleOfStockPricePerShareWeightedAveragePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mlys_MaximumAggregateOfferingPriceOfRemainingCommonSharesAvailableForSale" abstract="false" name="MaximumAggregateOfferingPriceOfRemainingCommonSharesAvailableForSale" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mlys_A2023IncentiveAwardPlanMember" abstract="true" name="A2023IncentiveAwardPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_A2025IncentiveAwardPlanMember" abstract="true" name="A2025IncentiveAwardPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_A2020EquityIncentivePlanMember" abstract="true" name="A2020EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_A2023EmployeeStockPurchasePlanMember" abstract="true" name="A2023EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mlys_EricWarrenMember" abstract="true" name="EricWarrenMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
