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  <xsd:element name="LicenseAgreementMilestonePaymentsPaid" id="hrmy_LicenseAgreementMilestonePaymentsPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" 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="AccruedMilestonePaymentCurrent" id="hrmy_AccruedMilestonePaymentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="LicenseAgreementLineItems" id="hrmy_LicenseAgreementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LicenseAgreementTable" id="hrmy_LicenseAgreementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <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="AccruedProfessionalFeesConsultingAndOtherServices" id="hrmy_AccruedProfessionalFeesConsultingAndOtherServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="MultiDrawLoanAgreementMember" id="hrmy_MultiDrawLoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CRGServicingLLCMember" id="hrmy_CRGServicingLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CreditAgreementMember" id="hrmy_CreditAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentExitFeePercentage" id="hrmy_DebtInstrumentExitFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element id="hrmy_DebtInstrumentExitFees" name="DebtInstrumentExitFees" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <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="UnderwritingDiscountsAndCommissionsAndOfferingExpenses" id="hrmy_UnderwritingDiscountsAndCommissionsAndOfferingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="TwoThousandSeventeenEquityIncentivePlanMember" id="hrmy_TwoThousandSeventeenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" 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="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonVestedWeightedAverageExercisePrice" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonVestedWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonVestedWeightedAverageExercisePriceGrantsInPeriod" id="hrmy_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonVestedWeightedAverageExercisePriceGrantsInPeriod" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="StockVestedDuringPeriodShares" id="hrmy_StockVestedDuringPeriodShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" 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="SecuritiesOutstandingIncludedInComputationOfUtilizingTreasuryStockMethod" id="hrmy_SecuritiesOutstandingIncludedInComputationOfUtilizingTreasuryStockMethod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockOptionAndStockStockAppreciationAndRestrictedStockUnitsMember" id="hrmy_StockOptionAndStockStockAppreciationAndRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeeStockOptionStockAppreciationRightsAndRestrictedStockUnitsMember" id="hrmy_EmployeeStockOptionStockAppreciationRightsAndRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ManagementServicesAgreementMember" id="hrmy_ManagementServicesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CurrentLiabilitiesMember" id="hrmy_CurrentLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" 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_TemporaryEquityValueConvertedToPermanentEquity" name="TemporaryEquityValueConvertedToPermanentEquity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="hrmy_TemporaryEquityShareConvertedToPermanentEquity" name="TemporaryEquityShareConvertedToPermanentEquity" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_RepurchaseAndCancellationOfCommonUnitsWithheldForTaxesShares" name="RepurchaseAndCancellationOfCommonUnitsWithheldForTaxesShares" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_ReclassificationOfWarrantLiabilityToEquity" name="ReclassificationOfWarrantLiabilityToEquity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="hrmy_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_FinancialInstrumentsAbstract" name="FinancialInstrumentsAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="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_ProductSaleNetPolicyTextBlock" name="ProductSaleNetPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_EmergingGrowthCompanyStatusPolicyPolicyTextBlock" name="EmergingGrowthCompanyStatusPolicyPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="hrmy_TwoCustomersMember" name="TwoCustomersMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" 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_RecognizedIncomeTaxPositionFromCurrentPeriodTaxPositions" name="RecognizedIncomeTaxPositionFromCurrentPeriodTaxPositions" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="hrmy_CommonStockNumberOfSharesSubjectToForfeitureProvisions" name="CommonStockNumberOfSharesSubjectToForfeitureProvisions" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="hrmy_ValuationAllowanceIncomeTaxExpenseBenefit" name="ValuationAllowanceIncomeTaxExpenseBenefit" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="hrmy_DeferredTaxAssetsDisallowedInterest" name="DeferredTaxAssetsDisallowedInterest" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <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_OperatingLossCarryforwardsExpirationPeriod" name="OperatingLossCarryforwardsExpirationPeriod" nillable="true" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <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_PaymentOfPreferredStockIssuanceCosts" name="PaymentOfPreferredStockIssuanceCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <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_RepaymentOfDebtCommencingOnDecember312021Member" name="RepaymentOfDebtCommencingOnDecember312021Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_RepaymentOfDebtBeginningOnMarch312024Member" name="RepaymentOfDebtBeginningOnMarch312024Member" 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_AllCountriesExcludingChinaMember" name="AllCountriesExcludingChinaMember" 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_IntellectualPropertyPaymentDueUponAchievementOfPreclinicalMilestones" name="IntellectualPropertyPaymentDueUponAchievementOfPreclinicalMilestones" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <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 id="hrmy_BlackstoneAlternativeCreditAdvisorsMember" name="BlackstoneAlternativeCreditAdvisorsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_RelatedPartyTransactionPaymentForAdvisoryFee" name="RelatedPartyTransactionPaymentForAdvisoryFee" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="hrmy_LongTermDebtDebtIssuanceCostsMember" name="LongTermDebtDebtIssuanceCostsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="hrmy_PaymentOfInitialPublicOfferingIssuanceCosts" name="PaymentOfInitialPublicOfferingIssuanceCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element name="DeferredRentAndTenantAllowance" id="hrmy_DeferredRentAndTenantAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" 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="InventorySoldExpensedAsResearchAndDevelopmentExpense" id="hrmy_InventorySoldExpensedAsResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AgreementRelatedToIntellectualPropertyPolicyTextBlock" id="hrmy_AgreementRelatedToIntellectualPropertyPolicyTextBlock" type="dtr-types:textBlockItemType" 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:schema>
