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  <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="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="SalesBasedTrademarkAndTieredRoyaltiesMember" id="hrmy_SalesBasedTrademarkAndTieredRoyaltiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <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="OperatingLeaseAdditionalOfficeSpaceLeasedOne" id="hrmy_OperatingLeaseAdditionalOfficeSpaceLeasedOne" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="OperatingLeaseAdditionalOfficeSpaceLeasedTwo" id="hrmy_OperatingLeaseAdditionalOfficeSpaceLeasedTwo" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <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="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="AdjustmentForAmortizationOfDebtIssuanceCosts" id="hrmy_AdjustmentForAmortizationOfDebtIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="October2023ShareRepurchaseProgramMember" id="hrmy_October2023ShareRepurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <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="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantsInPeriodWeightedAverageExercisePrice" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantsInPeriodWeightedAverageExercisePrice" 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="InProcessResearchAndDevelopmentAcquired" id="hrmy_InProcessResearchAndDevelopmentAcquired" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditsPercent" id="hrmy_EffectiveIncomeTaxRateReconciliationTaxCreditsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ResearchAndDevelopmentExpenseExcludingShareBasedCompensationAndInProcessResearchAndDevelopmentExpense" id="hrmy_ResearchAndDevelopmentExpenseExcludingShareBasedCompensationAndInProcessResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <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="GeneralAndAdministrativeExpenseExcludingShareBasedCompensationDepreciationAndAmortization" id="hrmy_GeneralAndAdministrativeExpenseExcludingShareBasedCompensationDepreciationAndAmortization" 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="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="ChiefStrategyOfficerMember" id="hrmy_ChiefStrategyOfficerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FormerChiefCommercialOfficerMember" id="hrmy_FormerChiefCommercialOfficerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ChiefFinancialOfficerAndChiefAdministrativeOfficerMember" id="hrmy_ChiefFinancialOfficerAndChiefAdministrativeOfficerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TradingArrangementExerciseOfOptionsMember" id="hrmy_TradingArrangementExerciseOfOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TradingArrangementVestingOfRestrictedStockUnitsMember" id="hrmy_TradingArrangementVestingOfRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <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="ParagonBiosciencesLlcMember" id="hrmy_ParagonBiosciencesLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfOperatingLeases" id="hrmy_NumberOfOperatingLeases" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PaymentOfUpfrontFeeInvestingActivities" id="hrmy_PaymentOfUpfrontFeeInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
</xsd:schema>
