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  <xs:element id="vnda_ProductRevenueAllowancesCurrent" abstract="false" name="ProductRevenueAllowancesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardServiceOptionAwardsFullAccelerationOfVestingInvoluntaryTerminationPeriodPostChangeOfControl" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardServiceOptionAwardsFullAccelerationOfVestingInvoluntaryTerminationPeriodPostChangeOfControl" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_IncreaseDecreaseProductRevenueAllowances" abstract="false" name="IncreaseDecreaseProductRevenueAllowances" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_CumulativeNetSalesToAchieveMilestone" abstract="false" name="CumulativeNetSalesToAchieveMilestone" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_TwoThousandSixPlanAndTwoThousandSixteenPlanMember" abstract="true" name="TwoThousandSixPlanAndTwoThousandSixteenPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndRestrictedStockUnitsRSUOutstandingNumber" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndRestrictedStockUnitsRSUOutstandingNumber" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="vnda_CustomerOneMember" abstract="true" name="CustomerOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_OrphanDrugMember" abstract="true" name="OrphanDrugMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_IncomeTaxesTable" abstract="true" name="IncomeTaxesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="vnda_ScheduleOfAccountsReceivableByMajorCustomersByReportingSegmentsTableTextBlock" abstract="false" name="ScheduleOfAccountsReceivableByMajorCustomersByReportingSegmentsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
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  <xs:element id="vnda_AccruedResearchAndDevelopmentExpense" abstract="false" name="AccruedResearchAndDevelopmentExpense" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_FanaptAbstract" abstract="true" name="FanaptAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_CustomerTwoMember" abstract="true" name="CustomerTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_AgreementsForClinicalAndMarketingServicesTerminationNoticePeriod" abstract="false" name="AgreementsForClinicalAndMarketingServicesTerminationNoticePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_OperatingLossCarryforwardsBeginningExpirationYear" abstract="false" name="OperatingLossCarryforwardsBeginningExpirationYear" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:gYearItemType"/>
  <xs:element id="vnda_HetliozAbstract" abstract="true" name="HetliozAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_IncomeBeforeIncomeTaxesCurrentYearMember" abstract="true" name="IncomeBeforeIncomeTaxesCurrentYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_SharebasedCompensationArrangementbyShareBasedPaymentAwardOptionsVestingPeriodNumberOfEqualMonthlyInstallments" abstract="false" name="SharebasedCompensationArrangementbyShareBasedPaymentAwardOptionsVestingPeriodNumberOfEqualMonthlyInstallments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="vnda_AccountsPayableAndAccruedLiabilitiesPolicyTextBlock" abstract="false" name="AccountsPayableAndAccruedLiabilitiesPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRestrictedStockUnitsLineItems" abstract="true" name="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRestrictedStockUnitsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_DeferredTaxAssetsTaxCreditCarryforwardsResearchAndOther" abstract="false" name="DeferredTaxAssetsTaxCreditCarryforwardsResearchAndOther" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_ScenarioFourMember" abstract="true" name="ScenarioFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_EffectiveIncomeTaxRateReconciliationUncertainTaxPositionsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationUncertainTaxPositionsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="vnda_RoyaltyPeriod" abstract="false" name="RoyaltyPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementbyShareBasedPaymentAnnualAwardVestingPeriodEmployeesandNewDirectors" abstract="false" name="ShareBasedCompensationArrangementbyShareBasedPaymentAnnualAwardVestingPeriodEmployeesandNewDirectors" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_VQW765Member" abstract="true" name="VQW765Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_SECSchedule1209AllowanceProductReturnsMember" abstract="true" name="SECSchedule1209AllowanceProductReturnsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_DeferredTaxAssetsLiabilitiesBeforeValuationAllowanceNet" abstract="false" name="DeferredTaxAssetsLiabilitiesBeforeValuationAllowanceNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_CustomerFourMember" abstract="true" name="CustomerFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_PercentageOfFutureSublicenseFeesPayable" abstract="false" name="PercentageOfFutureSublicenseFeesPayable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_OrphanDrugCreditBeginningExpirationYear" abstract="false" name="OrphanDrugCreditBeginningExpirationYear" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:gYearItemType"/>
  <xs:element id="vnda_StatementScenarioSecondaryAxis" abstract="true" name="StatementScenarioSecondaryAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="vnda_ScheduleOfLeaseAssetsAndLiabilitiesTableTextBlock" abstract="false" name="ScheduleOfLeaseAssetsAndLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_PercentageOfResponsibilityForPatientsCostOfBrandedPrescriptionUnderMedicarePartD" abstract="false" name="PercentageOfResponsibilityForPatientsCostOfBrandedPrescriptionUnderMedicarePartD" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="vnda_InventoryFinishedGoodsNetOfReservesNonCurrent" abstract="false" name="InventoryFinishedGoodsNetOfReservesNonCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardRemainingPercentageOfShareSubjectToOptionAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardRemainingPercentageOfShareSubjectToOptionAwards" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="vnda_DescriptionOfBusinessPolicyTextBlock" abstract="false" name="DescriptionOfBusinessPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_FanaptMember" abstract="true" name="FanaptMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_InventoryRawMaterialsNetOfReservesNonCurrent" abstract="false" name="InventoryRawMaterialsNetOfReservesNonCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_EstimatedRealizabilityofDeferredTaxAssetMember" abstract="true" name="EstimatedRealizabilityofDeferredTaxAssetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_FutureRegulatoryApprovalAndSalesMilestonesMember" abstract="true" name="FutureRegulatoryApprovalAndSalesMilestonesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_StockOptionsAndRestrictedStockUnitsRSUsMember" abstract="true" name="StockOptionsAndRestrictedStockUnitsRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_DevelopmentAndMilestoneObligationsPaidToThirdParty" abstract="false" name="DevelopmentAndMilestoneObligationsPaidToThirdParty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_RoyaltyPayableOnNetSalesPercentage" abstract="false" name="RoyaltyPayableOnNetSalesPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="vnda_CommitmentsAndContingenciesLineItems" abstract="true" name="CommitmentsAndContingenciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_EffectiveIncomeTaxRateReconciliationEffectiveTaxRateAdjustment" abstract="false" name="EffectiveIncomeTaxRateReconciliationEffectiveTaxRateAdjustment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="vnda_DevelopmentAndMilestonePaymentsPotentiallyDueToThirdParty" abstract="false" name="DevelopmentAndMilestonePaymentsPotentiallyDueToThirdParty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="vnda_ResearchAndDevelopmentCreditBeginningExpirationYear" abstract="false" name="ResearchAndDevelopmentCreditBeginningExpirationYear" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:gYearItemType"/>
  <xs:element id="vnda_TradipitantMember" abstract="true" name="TradipitantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="vnda_ReservesForVariableConsiderationPolicyTextBlock" abstract="false" name="ReservesForVariableConsiderationPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_InventoryAndOtherNonCurrent" abstract="false" name="InventoryAndOtherNonCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_PublicOfferingOfCommonStockTextBlock" abstract="false" name="PublicOfferingOfCommonStockTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_FuturePercentageOfRoyaltyPaymentsBasedOnNetSales" abstract="false" name="FuturePercentageOfRoyaltyPaymentsBasedOnNetSales" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="vnda_ScheduleOfInventoriesTableTextBlock" abstract="false" name="ScheduleOfInventoriesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfShareSubjectToOptionAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfShareSubjectToOptionAwards" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
</xs:schema>
