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  <element id="vstm_NumberOfBusinessDaysPriorWrittenNoticeForPrepayment" name="NumberOfBusinessDaysPriorWrittenNoticeForPrepayment" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_PercentageOfPrepaymentCharge" name="PercentageOfPrepaymentCharge" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentPercentageOfTotalPrincipalAmountAsFinalPayment" name="DebtInstrumentPercentageOfTotalPrincipalAmountAsFinalPayment" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentAdditionalInterestRateInEventOfDefault" name="DebtInstrumentAdditionalInterestRateInEventOfDefault" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_AccruedConsultingFeesCurrent" name="AccruedConsultingFeesCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_OtherAssetsPolicyTextBlock" name="OtherAssetsPolicyTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_CollaborativeArrangementsPeriodOfTimeForAverageClosingPriceOfShareOfCommonStock" name="CollaborativeArrangementsPeriodOfTimeForAverageClosingPriceOfShareOfCommonStock" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_LineOfCreditFacilityNumberOfSeparateAdvances" name="LineOfCreditFacilityNumberOfSeparateAdvances" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_FollowOnOfferingsMember" name="FollowOnOfferingsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_CollaborativeArrangementsMaximumReductionPercentage" name="CollaborativeArrangementsMaximumReductionPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_CollaborativeArrangementsPercentageOfAdditionalRoyalty" name="CollaborativeArrangementsPercentageOfAdditionalRoyalty" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_CollaborativeArrangementsPercentageOfUnitedStatesRoyaltyObligations" name="CollaborativeArrangementsPercentageOfUnitedStatesRoyaltyObligations" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_CollaborativeArrangementsPercentageOfRoyaltyReductionNonPatentRegulatoryExclusivity" name="CollaborativeArrangementsPercentageOfRoyaltyReductionNonPatentRegulatoryExclusivity" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentSecondTrancheMember" name="DebtInstrumentSecondTrancheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentThirdTrancheMember" name="DebtInstrumentThirdTrancheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentFourthTrancheMember" name="DebtInstrumentFourthTrancheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentInterestOnlyPaymentsExtendedMember" name="DebtInstrumentInterestOnlyPaymentsExtendedMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodTotalGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodTotalGrantDateFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPercentageOfPerformanceConditions" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPercentageOfPerformanceConditions" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionPercentageOfPerformanceConditionsNotConsideredProbableOfAchievement" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionPercentageOfPerformanceConditionsNotConsideredProbableOfAchievement" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_NumberOfCompaniesExpectedVolatilityIsBased" name="NumberOfCompaniesExpectedVolatilityIsBased" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_NumberOfCompaniesWithSimilarCharacteristicsToEntityIncludedInExpectedVolatilityComputation" name="NumberOfCompaniesWithSimilarCharacteristicsToEntityIncludedInExpectedVolatilityComputation" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentSecondAndThirdTrancheMember" name="DebtInstrumentSecondAndThirdTrancheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="vstm_DebtInstrumentFinalPaymentThreshold" name="DebtInstrumentFinalPaymentThreshold" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
