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  <xs:element id="nvax_ProceedsDevelopmentTechTransferLaunchAndSalesMilestoneCollaborationPaymentTerm" abstract="false" name="ProceedsDevelopmentTechTransferLaunchAndSalesMilestoneCollaborationPaymentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nvax_LicensingRoyaltiesAndOtherRevenue" abstract="false" name="LicensingRoyaltiesAndOtherRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_PfizerIncMember" abstract="true" name="PfizerIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_NumberOfDiseaseAreas" abstract="false" name="NumberOfDiseaseAreas" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nvax_CollaborationAgreementUpfrontPayment" abstract="false" name="CollaborationAgreementUpfrontPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_CollaborationAgreementMaximumDevelopmentalAndSalesMilestonePayments" abstract="false" name="CollaborationAgreementMaximumDevelopmentalAndSalesMilestonePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_ProceedsDevelopmentDevelopmentMilestoneCollaborationPayments" abstract="false" name="ProceedsDevelopmentDevelopmentMilestoneCollaborationPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_ProceedsDevelopmentSalesMilestoneCollaborationPayments" abstract="false" name="ProceedsDevelopmentSalesMilestoneCollaborationPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_ProceedsDevelopmentDevelopmentAndSalesMilestoneCollaborationPaymentsTerm" abstract="false" name="ProceedsDevelopmentDevelopmentAndSalesMilestoneCollaborationPaymentsTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nvax_CollaborationAgreementCompensateServices" abstract="false" name="CollaborationAgreementCompensateServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_AnnualMilestoneCollaborationPayments" abstract="false" name="AnnualMilestoneCollaborationPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_CollaborativeAgreementUpfrontPaymentReceivableAmountCreditableAgainstRoyalties" abstract="false" name="CollaborativeAgreementUpfrontPaymentReceivableAmountCreditableAgainstRoyalties" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_NoticePeriodForContractTermination" abstract="false" name="NoticePeriodForContractTermination" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nvax_ObligatedPurchasePriceOfRawMaterials" abstract="false" name="ObligatedPurchasePriceOfRawMaterials" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_RoyaltyPeriod" abstract="false" name="RoyaltyPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nvax_FivePointZeroConvertibleSeniorNotesDue2027Member" abstract="true" name="FivePointZeroConvertibleSeniorNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_DebtInstrumentExitFee" abstract="false" name="DebtInstrumentExitFee" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_TrancheAxisAxis" abstract="true" name="TrancheAxisAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="nvax_TrancheAxisDomain" abstract="true" name="TrancheAxisDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_Tranche1Member" abstract="true" name="Tranche1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_Tranche2Member" abstract="true" name="Tranche2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_Tranche3Member" abstract="true" name="Tranche3Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_Tranche4Member" abstract="true" name="Tranche4Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_PrepaymentYearAxis" abstract="true" name="PrepaymentYearAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="nvax_PrepaymentYearDomain" abstract="true" name="PrepaymentYearDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_YearOneMember" abstract="true" name="YearOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_YearTwoMember" abstract="true" name="YearTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_YearThreeMember" abstract="true" name="YearThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_DebtInstrumentVariableRateFloor" abstract="false" name="DebtInstrumentVariableRateFloor" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nvax_DebtInstrumentPrepaymentPenaltyPercentage" abstract="false" name="DebtInstrumentPrepaymentPenaltyPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nvax_DebtInstrumentExitFeePercentage" abstract="false" name="DebtInstrumentExitFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nvax_DebtInstrumentCovenantMinimumCashBalance" abstract="false" name="DebtInstrumentCovenantMinimumCashBalance" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_DebtInstrumentCovenantRoyaltyRevenuePeriod" abstract="false" name="DebtInstrumentCovenantRoyaltyRevenuePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nvax_ConvertibleSeniorNotesMember" abstract="true" name="ConvertibleSeniorNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_August2023SalesAgreementMember" abstract="true" name="August2023SalesAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_TwoThousandTwentyThreeStockInducementPlanMember" abstract="true" name="TwoThousandTwentyThreeStockInducementPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_TwoThousandFifteenStockIncentivePlanMember" abstract="true" name="TwoThousandFifteenStockIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForIssuance" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForIssuance" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="nvax_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantDateExercisePriceMinimumPercent" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantDateExercisePriceMinimumPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nvax_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfAnnualIncrease" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfAnnualIncrease" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nvax_A2023RestructuringPlanMember" abstract="true" name="A2023RestructuringPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_COVID19VaccineMember" abstract="true" name="COVID19VaccineMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_CICAndInfluenzaVaccinesMember" abstract="true" name="CICAndInfluenzaVaccinesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_OtherVaccineDevelopmentProgramsMember" abstract="true" name="OtherVaccineDevelopmentProgramsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nvax_ResearchAndDevelopmentExpenseSupplierFinanceProgram" abstract="false" name="ResearchAndDevelopmentExpenseSupplierFinanceProgram" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_ResearchAndDevelopmentExpenseEmployeeAndBenefitExpenses" abstract="false" name="ResearchAndDevelopmentExpenseEmployeeAndBenefitExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_ResearchAndDevelopmentExpenseFacilityAndOtherResearchAndDevelopmentExpenses" abstract="false" name="ResearchAndDevelopmentExpenseFacilityAndOtherResearchAndDevelopmentExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nvax_RestOfTheWorldMember" abstract="true" name="RestOfTheWorldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
