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  <xsd:import namespace="http://xbrl.sec.gov/stpr/2025" schemaLocation="https://xbrl.sec.gov/stpr/2025/stpr-2025.xsd" />
  <xsd:import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/ecd-sub/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-sub-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/cyd/2025" schemaLocation="https://xbrl.sec.gov/cyd/2025/cyd-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/cyd-af-sub/2025" schemaLocation="https://xbrl.sec.gov/cyd/2025/cyd-af-sub-2025.xsd" />
  <xsd:element name="StockAppreciationRightsMarketAdjustment" id="hrmy_StockAppreciationRightsMarketAdjustment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="PaymentsOfExtinguishmentOfDebtExitFees" id="hrmy_PaymentsOfExtinguishmentOfDebtExitFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hrmy_CashPaidForMilestones" name="CashPaidForMilestones" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element name="LiquidityAndCapitalResourcesTextBlock" id="hrmy_LiquidityAndCapitalResourcesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LiquidityAndCapitalResourcesAbstract" id="hrmy_LiquidityAndCapitalResourcesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OrganizationAndDescriptionOfBusinessLineItems" id="hrmy_OrganizationAndDescriptionOfBusinessLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OrganizationAndDescriptionOfBusinessTable" id="hrmy_OrganizationAndDescriptionOfBusinessTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfMajorCustomers" id="hrmy_NumberOfMajorCustomers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SummaryOfSignificantAccountingPoliciesLineItems" id="hrmy_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SummaryOfSignificantAccountingPoliciesTable" id="hrmy_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ThreeCustomersMember" id="hrmy_ThreeCustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CaremarkLLCMember" id="hrmy_CaremarkLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PANTHERxSpecialtyPharmacyLLCMember" id="hrmy_PANTHERxSpecialtyPharmacyLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccredoHealthGroupIncMember" id="hrmy_AccredoHealthGroupIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LicenseAgreementMilestonePaymentsPaid" id="hrmy_LicenseAgreementMilestonePaymentsPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WAKIXMember" id="hrmy_WAKIXMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LicenseAgreementMilestonePaymentsDue" id="hrmy_LicenseAgreementMilestonePaymentsDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="LicensingAgreementMilestoneFees" id="hrmy_LicensingAgreementMilestoneFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="AmountOfAggregateNetSalesAttaining" id="hrmy_AmountOfAggregateNetSalesAttaining" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="LicenseAgreementAdditionalMilestonePaymentsDue" id="hrmy_LicenseAgreementAdditionalMilestonePaymentsDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="UponAchievementOfAggregateNetSalesMember" id="hrmy_UponAchievementOfAggregateNetSalesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PitolisantsMember" id="hrmy_PitolisantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccruedRebatesAndOtherSalesDeductionsCurrent" id="hrmy_AccruedRebatesAndOtherSalesDeductionsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="AccruedResearchAndDevelopmentCurrent" id="hrmy_AccruedResearchAndDevelopmentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="UnamortizedDebtDiscountAssociatedWithExitFeeDebtFinancingCostsAndDiscountWithWarrantFinancing" id="hrmy_UnamortizedDebtDiscountAssociatedWithExitFeeDebtFinancingCostsAndDiscountWithWarrantFinancing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="OperatingLeaseOfficeSpace" id="hrmy_OperatingLeaseOfficeSpace" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncentiveAwardPlanTwoThousandTwentyMember" id="hrmy_IncentiveAwardPlanTwoThousandTwentyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TwoThousandSeventeenEquityIncentivePlanAndTwoThousandTwentyIncentiveAwardPlanMember" id="hrmy_TwoThousandSeventeenEquityIncentivePlanAndTwoThousandTwentyIncentiveAwardPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeeStockPurchasePlanMember" id="hrmy_EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsLackOfMarketabilityDiscount" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsLackOfMarketabilityDiscount" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SeniorSecuredTermLoanMember" id="hrmy_SeniorSecuredTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SeniorSecuredDelayedDrawTermLoanMember" id="hrmy_SeniorSecuredDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_SignificantRisksAndUncertaintiesPolicyTextBlock" name="SignificantRisksAndUncertaintiesPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_NumberOfApprovedCommercialProducts" name="NumberOfApprovedCommercialProducts" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_DeferredTaxAssetsLiabilitiesNetBeforeValuationAllowance" name="DeferredTaxAssetsLiabilitiesNetBeforeValuationAllowance" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="hrmy_PercentageOfChangeInOwnership" name="PercentageOfChangeInOwnership" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_PeriodOfChangeInOwnership" name="PeriodOfChangeInOwnership" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_BioprojetMember" name="BioprojetMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_RepaymentOfDebtDueOnMaturityDateMember" name="RepaymentOfDebtDueOnMaturityDateMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_AssetPurchaseAgreementWithConsynanceTherapeuticsMember" name="AssetPurchaseAgreementWithConsynanceTherapeuticsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_Hbs102Member" name="Hbs102Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_AssetAcquisitionsAxis" name="AssetAcquisitionsAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_AssetAcquisitionsDomain" name="AssetAcquisitionsDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscount" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="hrmy_IntellectualPropertyPaymentDueUponAchievementOfRegulatoryMilestones" name="IntellectualPropertyPaymentDueUponAchievementOfRegulatoryMilestones" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="hrmy_IntellectualPropertyPaymentDueUponAchievementOfDevelopmentalMilestones" name="IntellectualPropertyPaymentDueUponAchievementOfDevelopmentalMilestones" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="hrmy_IntellectualPropertyPaymentDueUponAchievementOfSalesMilestones" name="IntellectualPropertyPaymentDueUponAchievementOfSalesMilestones" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element name="OperatingLeaseAssetAbstract" id="hrmy_OperatingLeaseAssetAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DeferredTaxAssetsAccruedRebates" id="hrmy_DeferredTaxAssetsAccruedRebates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DeferredTaxAssetsLeaseObligationsNet" id="hrmy_DeferredTaxAssetsLeaseObligationsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationPercentageOfIncrementInCommonStockOutstandingAnnually" id="hrmy_ShareBasedCompensationPercentageOfIncrementInCommonStockOutstandingAnnually" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NdaForWakixMember" id="hrmy_NdaForWakixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DaytimeSleepinessMember" id="hrmy_DaytimeSleepinessMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CataplexyMember" id="hrmy_CataplexyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementFinalPaymentPaid" id="hrmy_LicenseAgreementFinalPaymentPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LongTermInvestmentsMember" id="hrmy_LongTermInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NonCurrentInvestmentMaturityTerm" id="hrmy_NonCurrentInvestmentMaturityTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAndAssetPurchaseAgreementsAbstract" id="hrmy_LicenseAndAssetPurchaseAgreementsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAndAssetPurchaseAgreementsTextBlock" id="hrmy_LicenseAndAssetPurchaseAgreementsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAndAssetPurchaseAgreementsTable" id="hrmy_LicenseAndAssetPurchaseAgreementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAndAssetPurchaseAgreementsLineItems" id="hrmy_LicenseAndAssetPurchaseAgreementsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShortTermCommercialPaperMember" id="hrmy_ShortTermCommercialPaperMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShortTermCorporateDebtSecuritiesMember" id="hrmy_ShortTermCorporateDebtSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LongTermCorporateDebtSecuritiesMember" id="hrmy_LongTermCorporateDebtSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LongTermUsGovernmentSecuritiesMember" id="hrmy_LongTermUsGovernmentSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ConcentrationsOfRiskNumberOfFinancialInstitutions" id="hrmy_ConcentrationsOfRiskNumberOfFinancialInstitutions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementUpfrontNonRefundableFeePaid" id="hrmy_LicenseAgreementUpfrontNonRefundableFeePaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementMaximumAdditionalMilestonePaymentsDue" id="hrmy_LicenseAgreementMaximumAdditionalMilestonePaymentsDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LongTermCommercialPaperMember" id="hrmy_LongTermCommercialPaperMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecSchedule1209AllowanceDistributionFeesDiscountsAndChargebacksMember" id="hrmy_SecSchedule1209AllowanceDistributionFeesDiscountsAndChargebacksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DeferredTaxAssetsResearchAndDevelopment" id="hrmy_DeferredTaxAssetsResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SalesBasedTrademarkAndTieredRoyaltiesMember" id="hrmy_SalesBasedTrademarkAndTieredRoyaltiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ValuationAndQualifyingAccountsDisclosureTableTextBlock" id="hrmy_ValuationAndQualifyingAccountsDisclosureTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementPreclinicalMilestonePaymentsRecognized" id="hrmy_LicenseAgreementPreclinicalMilestonePaymentsRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodValueStockOptionsAndRestrictedStockUnitsExercised" id="hrmy_StockIssuedDuringPeriodValueStockOptionsAndRestrictedStockUnitsExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesStockOptionsAndRestrictedStockUnitsExercised" id="hrmy_StockIssuedDuringPeriodSharesStockOptionsAndRestrictedStockUnitsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CommonStockNumberOfVotesPerShare" id="hrmy_CommonStockNumberOfVotesPerShare" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="FiveYearSeniorSecuredTermLoanMember" id="hrmy_FiveYearSeniorSecuredTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RepaymentOfDebtBeginningOnDecember312025Member" id="hrmy_RepaymentOfDebtBeginningOnDecember312025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RepaymentOfDebtCommencingOnDecember312023Member" id="hrmy_RepaymentOfDebtCommencingOnDecember312023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtInstrumentCreditSpreadAdjustmentRate" id="hrmy_DebtInstrumentCreditSpreadAdjustmentRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncrementalTermLoanMember" id="hrmy_IncrementalTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TermLoanMember" id="hrmy_TermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareRepurchasesPolicyTextBlock" id="hrmy_ShareRepurchasesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ZynerbaPharmaceuticalsInc.Member" id="hrmy_ZynerbaPharmaceuticalsInc.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdjustmentForAmortizationOfDebtIssuanceCosts" id="hrmy_AdjustmentForAmortizationOfDebtIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockRepurchasedAndRetiredDuringPeriodValueExclusiveOfCommissionsAndTransactionFees" id="hrmy_StockRepurchasedAndRetiredDuringPeriodValueExclusiveOfCommissionsAndTransactionFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="August2023ShareRepurchaseProgramMember" id="hrmy_August2023ShareRepurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="October2023ShareRepurchaseProgramMember" id="hrmy_October2023ShareRepurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NetProductRevenueTextBlock" id="hrmy_NetProductRevenueTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredOnCommonCashAmountPaidPerShare" id="hrmy_AssetAcquisitionConsiderationTransferredOnCommonCashAmountPaidPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredNumberOfContingentValueRightPerCommonStock" id="hrmy_AssetAcquisitionConsiderationTransferredNumberOfContingentValueRightPerCommonStock" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredCommonContingentValueRightPaidPerShare" id="hrmy_AssetAcquisitionConsiderationTransferredCommonContingentValueRightPaidPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholders" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptions" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholdersNumberOfSharesConsideredForCalculation" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholdersNumberOfSharesConsideredForCalculation" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholdersPricePerShareConsideredForCalculation" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSellingShareholdersPricePerShareConsideredForCalculation" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptionsNumberOfSharesConsideredForCalculation" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptionsNumberOfSharesConsideredForCalculation" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptionsPricePerShareConsideredForCalculation" id="hrmy_AssetAcquisitionConsiderationTransferredPaymentsMadeToSettleRestrictedStockAwardsAndStockOptionsPricePerShareConsideredForCalculation" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ZynerbaAcquisitionMember" id="hrmy_ZynerbaAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharesRepurchasedExciseTaxRate" id="hrmy_SharesRepurchasedExciseTaxRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="AccruedLiabilitiesOtherThanAccruedCompensationCurrent" id="hrmy_AccruedLiabilitiesOtherThanAccruedCompensationCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageRemainingContractualTerms" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageRemainingContractualTerms" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisedWeightedAverageExercisePrice" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisedWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="Orexin2ReceptorAgonistOx2rMember" id="hrmy_Orexin2ReceptorAgonistOx2rMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementUpfrontFeePaid" id="hrmy_LicenseAgreementUpfrontFeePaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementMaximumAdditionalMilestonePaymentsDueUponAchievementOfDevelopmentAndRegulatoryMilestones" id="hrmy_LicenseAgreementMaximumAdditionalMilestonePaymentsDueUponAchievementOfDevelopmentAndRegulatoryMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementMaximumAdditionalMilestonePaymentsDueUponAchievementOfSalesBasedMilestones" id="hrmy_LicenseAgreementMaximumAdditionalMilestonePaymentsDueUponAchievementOfSalesBasedMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EpygenixAcquisitionMember" id="hrmy_EpygenixAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionUpfrontConsiderationPaid" id="hrmy_AssetAcquisitionUpfrontConsiderationPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisable" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisable" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisableWeightedAverageExercisePrice" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisableWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisableWeightedAverageRemainingContractualTerms" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisableWeightedAverageRemainingContractualTerms" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingIntrinsicValue" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentExercisableIntrinsicValue" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentExercisableIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AcquiredInProcessResearchAndDevelopment" id="hrmy_AcquiredInProcessResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="InProcessResearchAndDevelopmentAcquired" id="hrmy_InProcessResearchAndDevelopmentAcquired" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BlackstoneCreditAgreementMember" id="hrmy_BlackstoneCreditAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SellingAndMarketingExpenseExcludingShareBasedCompensation" id="hrmy_SellingAndMarketingExpenseExcludingShareBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RareNeurologicalDiseasesSegmentMember" id="hrmy_RareNeurologicalDiseasesSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredCashPaidToSellingShareholdersAndToSettleRestrictedStockUnits" id="hrmy_AssetAcquisitionConsiderationTransferredCashPaidToSellingShareholdersAndToSettleRestrictedStockUnits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionConsiderationTransferredCashConsideration" id="hrmy_AssetAcquisitionConsiderationTransferredCashConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedWeightedAverageRemainingContractualTerm" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedWeightedAverageRemainingContractualTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedIntrinsicValue" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsUnvestedIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CiRCBiosciencesInc.Member" id="hrmy_CiRCBiosciencesInc.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementNumberOfDevelopmentalCandidates" id="hrmy_LicenseAgreementNumberOfDevelopmentalCandidates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementAdditionalMilestonePaymentsDueUponAchievementOfResearchMilestonesForEachCandidate" id="hrmy_LicenseAgreementAdditionalMilestonePaymentsDueUponAchievementOfResearchMilestonesForEachCandidate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementExerciseFeePayableUponExerciseOfExclusiveLicenseOptionForEachCandidate" id="hrmy_LicenseAgreementExerciseFeePayableUponExerciseOfExclusiveLicenseOptionForEachCandidate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicenseAgreementAggregateExerciseFeePayableUponExerciseOfExclusiveLicenseOptionForCandidates" id="hrmy_LicenseAgreementAggregateExerciseFeePayableUponExerciseOfExclusiveLicenseOptionForCandidates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PaymentOfUpfrontFeeInvestingActivities" id="hrmy_PaymentOfUpfrontFeeInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncomeTaxEffectChangeInLawAxis" id="hrmy_IncomeTaxEffectChangeInLawAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncomeTaxEffectChangeInLawDomain" id="hrmy_IncomeTaxEffectChangeInLawDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncomeTaxEffectUsPublicLaw11921Member" id="hrmy_IncomeTaxEffectUsPublicLaw11921Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LesseeOperatingLeaseNumberOfOfficeSuites" id="hrmy_LesseeOperatingLeaseNumberOfOfficeSuites" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LesseeOperatingLeaseRenewalFrequency" id="hrmy_LesseeOperatingLeaseRenewalFrequency" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LesseeOperatingLeaseEarlyTerminationOptionMonthNumber" id="hrmy_LesseeOperatingLeaseEarlyTerminationOptionMonthNumber" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfIncomeTaxPaidNetTableTextBlock" id="hrmy_ScheduleOfIncomeTaxPaidNetTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" id="hrmy_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" id="hrmy_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="OtherStatesMember" id="hrmy_OtherStatesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DepreciationAndImpairmentOfLongLivedAssets" id="hrmy_DepreciationAndImpairmentOfLongLivedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseExcludingShareBasedCompensationInProcessResearchAndDevelopmentExpenseAndImpairmentOfLongLivedAssets" id="hrmy_ResearchAndDevelopmentExpenseExcludingShareBasedCompensationInProcessResearchAndDevelopmentExpenseAndImpairmentOfLongLivedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeExpenseExcludingShareBasedCompensationAndAmortization" id="hrmy_GeneralAndAdministrativeExpenseExcludingShareBasedCompensationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PlymouthMeetingPaOfficeOneMember" id="hrmy_PlymouthMeetingPaOfficeOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PlymouthMeetingPaOfficeTwoMember" id="hrmy_PlymouthMeetingPaOfficeTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PlymouthMeetingPaOfficeThreeMember" id="hrmy_PlymouthMeetingPaOfficeThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ParagonBiosciencesLlcMember" id="hrmy_ParagonBiosciencesLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementMaximumDevelopmentMilestonePayments" id="hrmy_LicenseAgreementMaximumDevelopmentMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NumberOfNextGenerationsFormulationsInClinicalDevelopment" id="hrmy_NumberOfNextGenerationsFormulationsInClinicalDevelopment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfDiscoveryStageCandidates" id="hrmy_NumberOfDiscoveryStageCandidates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfMajorSuppliers" id="hrmy_NumberOfMajorSuppliers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
