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  <xsd:element abstract="true" id="exel_CollaborativeArrangementwithTakedaMember" name="CollaborativeArrangementwithTakedaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_CollaborativeArrangementwithTwoBristolMyersSquibbCompoundUtilizedMemberMember" name="CollaborativeArrangementwithTwoBristolMyersSquibbCompoundUtilizedMemberMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_CollateralProvidedForPurchasingCardProgram" name="CollateralProvidedForPurchasingCardProgram" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_CometriqMember" name="CometriqMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ComputerEquipmentAndSoftwareMember" name="ComputerEquipmentAndSoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ContractRevenueMember" name="ContractRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element id="exel_CostMethodInvestmentOwnershipPercentage" name="CostMethodInvestmentOwnershipPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_CotellicMember" name="CotellicMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_CouponInterestMember" name="CouponInterestMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_DebtInstrumentInterestRateStatedPercentageafterExtensionOptionElection" name="DebtInstrumentInterestRateStatedPercentageafterExtensionOptionElection" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="exel_DebtInstrumentNumberofInstruments" name="DebtInstrumentNumberofInstruments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_DebtInstrumentPrepaymentPenalty" name="DebtInstrumentPrepaymentPenalty" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
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  <xsd:element id="exel_DeferredTaxAssetsAmortizationOfDeferredStockCompensationNonQualified" name="DeferredTaxAssetsAmortizationOfDeferredStockCompensationNonQualified" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="exel_DefinedContributionPlanNumberofSharesAvailableforGrant" name="DefinedContributionPlanNumberofSharesAvailableforGrant" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_DiplomatSpecialtyPharmacyMember" name="DiplomatSpecialtyPharmacyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_DiscountsandAllowances" name="DiscountsandAllowances" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_EffectiveIncomeTaxRateReconciliationExtinguishmentofDebtAmount" name="EffectiveIncomeTaxRateReconciliationExtinguishmentofDebtAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_EligiblePaymentFromCollaborationForDevelopmentAndRegulatoryMilestoneAchievementUnderCollaborationsAgreement" name="EligiblePaymentFromCollaborationForDevelopmentAndRegulatoryMilestoneAchievementUnderCollaborationsAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_EquipmentAndFurnitureMember" name="EquipmentAndFurnitureMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_EstimatedUsefulLivesOfPropertyPlantAndEquipmentTableTextBlock" name="EstimatedUsefulLivesOfPropertyPlantAndEquipmentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ExtinguishmentofDebtDifferenceBetweenSettlementConsiderationandNetCarryingValue" name="ExtinguishmentofDebtDifferenceBetweenSettlementConsiderationandNetCarryingValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_ExtinguishmentofDebtIncludingPaidinKindInterest" name="ExtinguishmentofDebtIncludingPaidinKindInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_ExtinguishmentofDebtWriteoffofUnamortizedDebtDiscounts" name="ExtinguishmentofDebtWriteoffofUnamortizedDebtDiscounts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="exel_GlobalMember" name="GlobalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_HCCAcceptanceMember" name="HCCAcceptanceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_HCCFilingMember" name="HCCFilingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseAccruedClinicalLiabilities" name="IncreaseDecreaseAccruedClinicalLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseinAccruedCollaborationLiability" name="IncreaseDecreaseinAccruedCollaborationLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="exel_IpsenMember" name="IpsenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeLeasingArrangementsCapitalandOperatingLeasesMinimumLeasePaymentsDue" name="LesseeLeasingArrangementsCapitalandOperatingLeasesMinimumLeasePaymentsDue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_LesseeLeasingArrangementsCapitalandOperatingLeasesRenewalTerm" name="LesseeLeasingArrangementsCapitalandOperatingLeasesRenewalTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeLeasingArrangementsCapitalandOperatingLeasesTermofContract" name="LesseeLeasingArrangementsCapitalandOperatingLeasesTermofContract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LossonExtinguishmentofDebtTransactionCosts" name="LossonExtinguishmentofDebtTransactionCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_MaximumAmountEligibleForCommercialMilestonesUnderCollaborationsAgreement" name="MaximumAmountEligibleForCommercialMilestonesUnderCollaborationsAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_MaximumAmountEligibleForRoyaltiesOnSalesUnderCollaborationsAgreement" name="MaximumAmountEligibleForRoyaltiesOnSalesUnderCollaborationsAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_MaximumPotentialMilestonePayments" name="MaximumPotentialMilestonePayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_MilestoneObjectiveAxis" name="MilestoneObjectiveAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_MilestoneObjectiveDomain" name="MilestoneObjectiveDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_NumberofProductsinCommercialMarket" name="NumberofProductsinCommercialMarket" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OperatingLeaseMember" name="OperatingLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OperatingLeaseandOtherFinancingLeaseMember" name="OperatingLeaseandOtherFinancingLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OptionalAmendmentAgreementMember" name="OptionalAmendmentAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OrganizationAndSummaryOfSignificantPoliciesLineItems" name="OrganizationAndSummaryOfSignificantPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="exel_OtherLongtermAssetsMember" name="OtherLongtermAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_PaymentOfReimbursementsFromCollaborationArrangement" name="PaymentOfReimbursementsFromCollaborationArrangement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_PaymentandCreditsIssued" name="PaymentandCreditsIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_PaymentinKindInterestMember" name="PaymentinKindInterestMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_PaymentsforConversionofConvertibleDebt" name="PaymentsforConversionofConvertibleDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_PaymentsforInducementsofDebtConversion" name="PaymentsforInducementsofDebtConversion" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_PercentOfRoyaltyOnNetSale" name="PercentOfRoyaltyOnNetSale" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_PercentageofMaximumPotentialMilestonePaymentsClinicalDevelopment" name="PercentageofMaximumPotentialMilestonePaymentsClinicalDevelopment" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="exel_PercentageofMaximumPotentialMilestonePaymentsCommercial" name="PercentageofMaximumPotentialMilestonePaymentsCommercial" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="exel_PercentageofMaximumPotentialMilestonePaymentsRegulatory" name="PercentageofMaximumPotentialMilestonePaymentsRegulatory" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_PerformanceStockOptionsMember" name="PerformanceStockOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_PeriodOfSpecificSalesVolumeThreshold" name="PeriodOfSpecificSalesVolumeThreshold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProductsDerivedfromCabozantinibMember" name="ProductsDerivedfromCabozantinibMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ProfitSharingAgreementOptionalPercentOfTotalSalesForce" name="ProfitSharingAgreementOptionalPercentOfTotalSalesForce" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ProfitSharingAgreementPercentOfProfits" name="ProfitSharingAgreementPercentOfProfits" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ProfitSharingAgreementProfitThreshold" name="ProfitSharingAgreementProfitThreshold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProfitSharingTierOneMember" name="ProfitSharingTierOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProfitSharingTierThreeMember" name="ProfitSharingTierThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProfitSharingTierTwoMember" name="ProfitSharingTierTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="exel_RebatesMember" name="RebatesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_RecoveryOfExpensesExpensesInCurrentFiscalYear" name="RecoveryOfExpensesExpensesInCurrentFiscalYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_RecoveryofExpensesExpensesPriortoCurrentFiscalYear" name="RecoveryofExpensesExpensesPriortoCurrentFiscalYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_ResearchandDevelopmentArrangementPerformedforOthersReimbursementforCostsIncurredPercent" name="ResearchandDevelopmentArrangementPerformedforOthersReimbursementforCostsIncurredPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ReserveRollforwardRollForward" name="ReserveRollforwardRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_RestofWorldMember" name="RestofWorldMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_RoyaltyTier" name="RoyaltyTier" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_RoyaltytierAxis" name="RoyaltytierAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_RoyaltytierDomain" name="RoyaltytierDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SalesRevenueDiscountExpectedtobeEarnedPercent" name="SalesRevenueDiscountExpectedtobeEarnedPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SalesRevenuePercentDiscountForPromptPayment" name="SalesRevenuePercentDiscountForPromptPayment" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_SanofiAventisMember" name="SanofiAventisMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_SecondMember" name="SecondMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SecuredConvertibleNotesDueJune2018Member" name="SecuredConvertibleNotesDueJune2018Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedandReleased" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedandReleased" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedandReleasedinPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedandReleasedinPeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpensedFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpensedFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_SharebasedCompensationArrangementbySharebasedPaymentAwardDiscountfromMarketPriceOfferingDatePurchasePeriod" name="SharebasedCompensationArrangementbySharebasedPaymentAwardDiscountfromMarketPriceOfferingDatePurchasePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SharebasedCompensationArrangementbySharebasedPaymentAwardExercisePeriodExtension" name="SharebasedCompensationArrangementbySharebasedPaymentAwardExercisePeriodExtension" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SharebasedCompensationArrangementbySharebasedPaymentAwardTerminationPeriodPriortoChangeinControl" name="SharebasedCompensationArrangementbySharebasedPaymentAwardTerminationPeriodPriortoChangeinControl" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SharebasedCompensationArrangementbySharebasedPaymentAwardTerminationPeriodSubsequenttoChangeinControl" name="SharebasedCompensationArrangementbySharebasedPaymentAwardTerminationPeriodSubsequenttoChangeinControl" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SharesWithheldforConversionofWarrants" name="SharesWithheldforConversionofWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SiliconValleyBankLoanAndSecurityAgreementMember" name="SiliconValleyBankLoanAndSecurityAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_SouthSanFranciscoCaliforniaMember" name="SouthSanFranciscoCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_StandbyLetterOfCreditRelatedToBuildingLeaseMember" name="StandbyLetterOfCreditRelatedToBuildingLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_StandbyLetterOfCreditRelatedToWorkersCompensationInsurancePolicyMember" name="StandbyLetterOfCreditRelatedToWorkersCompensationInsurancePolicyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_TaxCutsandJobsActof2017ChangeinTaxRateEffectOnDeferredTaxAssetsGross" name="TaxCutsandJobsActof2017ChangeinTaxRateEffectOnDeferredTaxAssetsGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_TaxCutsandJobsActof2017ChangeinTaxRateEffectOnDeferredTaxAssetsValuationAllowance" name="TaxCutsandJobsActof2017ChangeinTaxRateEffectOnDeferredTaxAssetsValuationAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_TenantLeaseImprovementsAllowance" name="TenantLeaseImprovementsAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_UnrecognizedTaxBenefitsIncreaseDecreaseResultingfromPriorPeriodTaxPositions" name="UnrecognizedTaxBenefitsIncreaseDecreaseResultingfromPriorPeriodTaxPositions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_UpfrontAndMilestonePayments" name="UpfrontAndMilestonePayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_WarrantsIssuedOnJanuaryTwentySecondTwoThousandAndFourteenMember" name="WarrantsIssuedOnJanuaryTwentySecondTwoThousandAndFourteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
