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  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumPerformanceConditionSatisfactionPeriod" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumPerformanceConditionSatisfactionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EarlyExercisableEmployeeStockOptionsMember" id="alms_EarlyExercisableEmployeeStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherPrepaidExpenseAndAssetsCurrent" id="alms_OtherPrepaidExpenseAndAssetsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AccretionExpenseNetOfDiscountsOnMarketableSecurities" id="alms_AccretionExpenseNetOfDiscountsOnMarketableSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementShareBasedPaymentAwardMaximumTerm" id="alms_ShareBasedCompensationArrangementShareBasedPaymentAwardMaximumTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsIssuedInPeriodFairValue" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsIssuedInPeriodFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardDerivedServicePeriod" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardDerivedServicePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInNumberOfSharesReservedAndAvailableForIssuance" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInNumberOfSharesReservedAndAvailableForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePricePercentageOnMarketPriceOfferingDate" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePricePercentageOnMarketPriceOfferingDate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfDaysPriorNoticeToIncreaseOrDecreaseInterestThresholdLimit" id="alms_NumberOfDaysPriorNoticeToIncreaseOrDecreaseInterestThresholdLimit" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CommonStockConversionMaximumBeneficialOwnershipPercentAfterConversion" id="alms_CommonStockConversionMaximumBeneficialOwnershipPercentAfterConversion" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="SharesAuthorizedToBeAddedFromAnotherPlan" id="alms_SharesAuthorizedToBeAddedFromAnotherPlan" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="MaximumGrantDateFairMarketValueAndCashCompensationPaid" id="alms_MaximumGrantDateFairMarketValueAndCashCompensationPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AcelyrinIncMember" id="alms_AcelyrinIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentFacilitiesAndOverheadCosts" id="alms_ResearchAndDevelopmentFacilitiesAndOverheadCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SingleReportableSegmentMember" id="alms_SingleReportableSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExternalCostAbstract" id="alms_ResearchAndDevelopmentExternalCostAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentInternalCostAbstract" id="alms_ResearchAndDevelopmentInternalCostAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentProfessionalConsultingServicesCosts" id="alms_ResearchAndDevelopmentProfessionalConsultingServicesCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentPersonnelRelatedCosts" id="alms_ResearchAndDevelopmentPersonnelRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedAndEarlyExercisableNumber" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedAndEarlyExercisableNumber" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="KakenPharmaceuticalCo.LtdMember" id="alms_KakenPharmaceuticalCo.LtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CollaborativeArrangementForProductEsk001Member" id="alms_CollaborativeArrangementForProductEsk001Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromUpfrontNonRefundablePayment" id="alms_ProceedsFromUpfrontNonRefundablePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GlobalDevelopmentCostsReceivable" id="alms_GlobalDevelopmentCostsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommonStockCapitalSharesReservedForFutureIssuancePeriodIncreaseDecrease" id="alms_CommonStockCapitalSharesReservedForFutureIssuancePeriodIncreaseDecrease" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="MaximumAmountReceivableUponAchievementOfRegulatoryMilestones" id="alms_MaximumAmountReceivableUponAchievementOfRegulatoryMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="MaximumAmountReceivableUponAchievementOfCommercialMilestones" id="alms_MaximumAmountReceivableUponAchievementOfCommercialMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="MergerAgreementExchangeRatio" id="alms_MergerAgreementExchangeRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfPerformanceConditionsAchieved" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfPerformanceConditionsAchieved" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfEqualInstallmentsForVesting" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfEqualInstallmentsForVesting" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PerformanceBasedRestrictedStockUnitsMember" id="alms_PerformanceBasedRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MergerClosesBeforeMay152025Member" id="alms_MergerClosesBeforeMay152025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RevenueLicenseObligationAllocatedAmount" id="alms_RevenueLicenseObligationAllocatedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RevenueMaterialRightObligationAllocatedAmount" id="alms_RevenueMaterialRightObligationAllocatedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RevenueDevelopmentServicesObligationAllocatedAmount" id="alms_RevenueDevelopmentServicesObligationAllocatedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ClinicalResearchOrganizationsContractManufacturingOrganizationsAndClinicalTrials" id="alms_ClinicalResearchOrganizationsContractManufacturingOrganizationsAndClinicalTrials" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ScheduleOfWeightedAverageRemainingLeaseTermAndIncrementalBorrowingRateForOperatingLeasesTableTextBlock" id="alms_ScheduleOfWeightedAverageRemainingLeaseTermAndIncrementalBorrowingRateForOperatingLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfSupplementalCashFlowInformationRelatedToOperatingLeasesTableTextBlock" id="alms_ScheduleOfSupplementalCashFlowInformationRelatedToOperatingLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="GlobalDevelopmentCostReimbursementDermatologyFieldThroughEndOf2026Member" id="alms_GlobalDevelopmentCostReimbursementDermatologyFieldThroughEndOf2026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GlobalDevelopmentCostReimbursementDermatologyFieldAfter2026Member" id="alms_GlobalDevelopmentCostReimbursementDermatologyFieldAfter2026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RevenuePerformanceObligationAxis" id="alms_RevenuePerformanceObligationAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RevenuePerformanceObligationDomain" id="alms_RevenuePerformanceObligationDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DevelopmentServicesObligationMember" id="alms_DevelopmentServicesObligationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MaterialRightObligationMember" id="alms_MaterialRightObligationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredMarketableSecuritiesCurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredMarketableSecuritiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredResearchAndDevelopmentPrepaidExpenseCurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredResearchAndDevelopmentPrepaidExpenseCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredPrepaidCreditVoucherCurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredPrepaidCreditVoucherCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredOtherPrepaidExpenseAndAssetsCurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredOtherPrepaidExpenseAndAssetsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredRestrictedCashNoncurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredRestrictedCashNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAssetNoncurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAssetNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedAccruedResearchAndDevelopmentExpensesCurrent" id="alms_BusinessCombinationRecognizedLiabilityAssumedAccruedResearchAndDevelopmentExpensesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedOtherAccruedExpensesAndLiabilitiesCurrent" id="alms_BusinessCombinationRecognizedLiabilityAssumedOtherAccruedExpensesAndLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedOperatingLeaseLiabilitiesCurrent" id="alms_BusinessCombinationRecognizedLiabilityAssumedOperatingLeaseLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedOperatingLeaseLiabilitiesNoncurrent" id="alms_BusinessCombinationRecognizedLiabilityAssumedOperatingLeaseLiabilitiesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AcelyrinPlansMember" id="alms_AcelyrinPlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAssumedInPeriod" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAssumedInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseInOtherPrepaidExpensesAndOtherCurrentAssets" id="alms_IncreaseDecreaseInOtherPrepaidExpensesAndOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DispositionOfAssetsMaximumDevelopmentCommercialAndRegulatoryMilestonesPaymentsReceivable" id="alms_DispositionOfAssetsMaximumDevelopmentCommercialAndRegulatoryMilestonesPaymentsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="Acelyrin2023EquityIncentivePlanMember" id="alms_Acelyrin2023EquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PierreFabreMember" id="alms_PierreFabreMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAndCommercializationAgreementMember" id="alms_LicenseAndCommercializationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CollaborativeArrangementMaximumMilestonePaymentUponAchievementOfDevelopmentAndRegulatoryMilestones" id="alms_CollaborativeArrangementMaximumMilestonePaymentUponAchievementOfDevelopmentAndRegulatoryMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CollaborativeArrangementMaximumMilestonePaymentUponAchievementOfCertainCommercialMilestones" id="alms_CollaborativeArrangementMaximumMilestonePaymentUponAchievementOfCertainCommercialMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CollaborativeArrangementRoyaltyPaymentExpirationPeriodFromFirstCommercialSaleOfLicensedProduct" id="alms_CollaborativeArrangementRoyaltyPaymentExpirationPeriodFromFirstCommercialSaleOfLicensedProduct" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CollaborativeArrangementPriorWrittenNoticePeriodForTerminationOfAgreement" id="alms_CollaborativeArrangementPriorWrittenNoticePeriodForTerminationOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriod" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriodWeightedAverageGrantDateFairValue" id="alms_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationIndefiniteLivedIntangibleAssetsMeasurementDiscountRate" id="alms_BusinessCombinationIndefiniteLivedIntangibleAssetsMeasurementDiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="BusinessCombinationNumberOfOperatingLeasesAcquired" id="alms_BusinessCombinationNumberOfOperatingLeasesAcquired" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredCreditVouchersExceptClinicalProductManufacturingCurrent" id="alms_BusinessCombinationRecognizedAssetAcquiredCreditVouchersExceptClinicalProductManufacturingCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLeaseLiabilitiesShortTermPortionFairValueAdjustments" id="alms_OperatingLeaseLiabilitiesShortTermPortionFairValueAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLeaseLiabilitiesLongTermPortionFairValueAdjustments" id="alms_OperatingLeaseLiabilitiesLongTermPortionFairValueAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLeaseRightOfUseAssetsFairValueAdjustments" id="alms_OperatingLeaseRightOfUseAssetsFairValueAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RestructuringObligationsPayableCash" id="alms_RestructuringObligationsPayableCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RestructuringObligationsPayableCashPaymentPeriod" id="alms_RestructuringObligationsPayableCashPaymentPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseObligationMember" id="alms_LicenseObligationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetPledgedAsCollateralForLeaseCommitmentsMember" id="alms_AssetPledgedAsCollateralForLeaseCommitmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationConsiderationTransferredFairValueOfReplacementAwards" id="alms_BusinessCombinationConsiderationTransferredFairValueOfReplacementAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="MonthlyRentPayments" id="alms_MonthlyRentPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AnnualIncreaseInMonthlyRentPaymentPercentage" id="alms_AnnualIncreaseInMonthlyRentPaymentPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PrepaidCreditVoucherForClinicalManufacturingCurrent" id="alms_PrepaidCreditVoucherForClinicalManufacturingCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockOptionPlansExcludingPerformanceOptionPlan2024Member" id="alms_StockOptionPlansExcludingPerformanceOptionPlan2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NonPerformancePlansMember" id="alms_NonPerformancePlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CollaborationRevenueMember" id="alms_CollaborationRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredRestrictedCash" id="alms_BusinessCombinationRecognizedAssetAcquiredRestrictedCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PrepaidCreditVoucherForClinicalManufacturingNonCurrent" id="alms_PrepaidCreditVoucherForClinicalManufacturingNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BalanceSheetComponentsTable" id="alms_BalanceSheetComponentsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BalanceSheetComponentsLineItem" id="alms_BalanceSheetComponentsLineItem" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SupranationalDebtObligationsMember" id="alms_SupranationalDebtObligationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GovernmentDevelopmentBankObligationsMember" id="alms_GovernmentDevelopmentBankObligationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UnderwritersOptionPeriod" id="alms_UnderwritersOptionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DeferralContributionUpToThreePercentMember" id="alms_DeferralContributionUpToThreePercentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DeferralContributionBetweenThreePercentAndFivePercentMember" id="alms_DeferralContributionBetweenThreePercentAndFivePercentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AtMarketSharesMember" id="alms_AtMarketSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SaleOfStockMaximumCommissionPercentageUnderAgreement" id="alms_SaleOfStockMaximumCommissionPercentageUnderAgreement" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="MaximumValueOfStockIssuableUnderAgreement" id="alms_MaximumValueOfStockIssuableUnderAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="Plan2024Member" id="alms_Plan2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherThanPlan2024Member" id="alms_OtherThanPlan2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommonStockMaximumNumberForOptionToPurchase" id="alms_CommonStockMaximumNumberForOptionToPurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AdditionalSeveranceEntitledPeriod" id="alms_AdditionalSeveranceEntitledPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AdditionalSeveranceMaximumOptionExercisePeriodExtensionPeriod" id="alms_AdditionalSeveranceMaximumOptionExercisePeriodExtensionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EmployeeStockPurchasePlanAutomaticIncreasePeriod" id="alms_EmployeeStockPurchasePlanAutomaticIncreasePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LossContingencyValueInDispute" id="alms_LossContingencyValueInDispute" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ClimbBioInc.Member" id="alms_ClimbBioInc.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReceivableRecordedForStockOptionExercisesPendingSettlement" id="alms_ReceivableRecordedForStockOptionExercisesPendingSettlement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalVestingOfEarlyExercisedStockOptions" id="alms_AdjustmentsToAdditionalPaidInCapitalVestingOfEarlyExercisedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalVestingOfRestrictedSharesOfCommonStock" id="alms_AdjustmentsToAdditionalPaidInCapitalVestingOfRestrictedSharesOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTaxCurrent" id="alms_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTaxCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxCurrent" id="alms_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxNonCurrent" id="alms_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTaxNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
</xsd:schema>
