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  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRemainingPerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRemainingPerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="vnda_EffectiveIncomeTaxRateReconciliationNonCashChangeInDeferredTaxAssetsValuationAllowanceAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNonCashChangeInDeferredTaxAssetsValuationAllowanceAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="vnda_ProductSegmentsMember" abstract="true" name="ProductSegmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
