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<!--Created on: 5/6/2015 8:49:10 AM-->
<!--Modified on: 5/6/2015 8:49:10 AM-->
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  <xsd:element name="WarrantToPurchaseCommonStockMember" id="supn_WarrantToPurchaseCommonStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BasisOfPresentationAbstract" id="supn_BasisOfPresentationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OperatingLeasesOptionalLeaseExtensionPeriod" id="supn_OperatingLeasesOptionalLeaseExtensionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OperatingLeasesAdditionalAllowanceForTenantAndCapitalImprovement" id="supn_OperatingLeasesAdditionalAllowanceForTenantAndCapitalImprovement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="OperatingLeasesAllowanceForTenantAndCapitalImprovementCapitalized" id="supn_OperatingLeasesAllowanceForTenantAndCapitalImprovementCapitalized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="EquityIncentivePlan2012Member" id="supn_EquityIncentivePlan2012Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingNumberOfInstallmentsFromFirstAnniversaryOfGrantDate" id="supn_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingNumberOfInstallmentsFromFirstAnniversaryOfGrantDate" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FiniteLivedIntangibleAssetsEstimatedAnnualAggregateAmortizationExpense" id="supn_FiniteLivedIntangibleAssetsEstimatedAnnualAggregateAmortizationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="NumberOfProprietaryProductsInClinicalDevelopment" id="supn_NumberOfProprietaryProductsInClinicalDevelopment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccruedClinicalTrialAndClinicalSupplyCostsCurrent" id="supn_AccruedClinicalTrialAndClinicalSupplyCostsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="SalesReturnPeriod" id="supn_SalesReturnPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DeferredRevenueLicensingCurrent" id="supn_DeferredRevenueLicensingCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="DeferredRevenueLicensingNoncurrent" id="supn_DeferredRevenueLicensingNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="IncreaseDecreaseInDeferredProductRevenueNet" id="supn_IncreaseDecreaseInDeferredProductRevenueNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInDeferredLicensingRevenue" id="supn_IncreaseDecreaseInDeferredLicensingRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="DebtInstrumentConvertibleAdditionalInformationAbstract" id="supn_DebtInstrumentConvertibleAdditionalInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DebtConversionConvertedInstrumentSharesIssuedInSettlementOfInterestMakeWholeProvision" id="supn_DebtConversionConvertedInstrumentSharesIssuedInSettlementOfInterestMakeWholeProvision" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="InterestMakeWholeLiabilityMember" id="supn_InterestMakeWholeLiabilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FairValueAssumptionsCreditSpread" id="supn_FairValueAssumptionsCreditSpread" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AllowanceForExpectedPromptPayDiscounts" id="supn_AllowanceForExpectedPromptPayDiscounts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="FairValueOfInterestMakeWholeDerivative" id="supn_FairValueOfInterestMakeWholeDerivative" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <element id="supn_OxtellarXRMember" name="OxtellarXRMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="supn_TrokendiXrMember" name="TrokendiXrMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="supn_AccruedSalesDeduction" name="AccruedSalesDeduction" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="supn_OperatingLeasesAmountAvailableForTenantImprovements" name="OperatingLeasesAmountAvailableForTenantImprovements" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="supn_StockOptionsStockAppreciationRightsNonVestedStockOptionsAndEsppAwardsMember" name="StockOptionsStockAppreciationRightsNonVestedStockOptionsAndEsppAwardsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="supn_IncrementalCommonSharesAttributableToStockOptionsStockAppreciationRightsAndNonVestedStockOptionsAndEsppAward" name="IncrementalCommonSharesAttributableToStockOptionsStockAppreciationRightsAndNonVestedStockOptionsAndEsppAward" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>





