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  <xsd:element abstract="true" id="vxrt_FirstSetOfWarrantsExpiringApril2024Member" name="FirstSetOfWarrantsExpiringApril2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_FirstSetOfWarrantsExpiringSeptember2024Member" name="FirstSetOfWarrantsExpiringSeptember2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_FutureGrantsOfEquityAwardsMember" name="FutureGrantsOfEquityAwardsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_GainLossOnMerger" name="GainLossOnMerger" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_GainOnRemeasurementOfFutureRoyaltyLiability" name="GainOnRemeasurementOfFutureRoyaltyLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_GrantMilestoneCompletionMember" name="GrantMilestoneCompletionMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_GrossProceedsFromIssuanceOfCommonStock" name="GrossProceedsFromIssuanceOfCommonStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_HCRPMember" name="HCRPMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_HealthcareRoyaltyIIILPMember" name="HealthcareRoyaltyIIILPMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_HimmelbergVVaxartIncEtAlMember" name="HimmelbergVVaxartIncEtAlMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_InvestmentsAndCashFairValueDisclosure" name="InvestmentsAndCashFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="vxrt_June2023OfferingMember" name="June2023OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_LeaseForFacilityInSouthSanFranciscoCaliforniaMember" name="LeaseForFacilityInSouthSanFranciscoCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_LeaseForFacilityInSouthSanFranciscoCommencedInFirstQuarterOf2023Member" name="LeaseForFacilityInSouthSanFranciscoCommencedInFirstQuarterOf2023Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_LesseeOperatingLeaseNumberOfLeases" name="LesseeOperatingLeaseNumberOfLeases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_LesseeOperatingLeaseNumberOfRenewalOption" name="LesseeOperatingLeaseNumberOfRenewalOption" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_LesseeShortTermLeaseNumberOfLeases" name="LesseeShortTermLeaseNumberOfLeases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_LiabilitiesRelatedToSaleOfFutureRoyaltiesTextBlock" name="LiabilitiesRelatedToSaleOfFutureRoyaltiesTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_LiabilityRelatedToSaleOfFutureRoyalties" name="LiabilityRelatedToSaleOfFutureRoyalties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_LiabilityRelatedToSaleOfFutureRoyaltiesCurrent" name="LiabilityRelatedToSaleOfFutureRoyaltiesCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_LiabilityRelatedToSaleOfFutureRoyaltiesNoncurrent" name="LiabilityRelatedToSaleOfFutureRoyaltiesNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_NetProceedsFromIssuanceOfCommonStock" name="NetProceedsFromIssuanceOfCommonStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_NonCashRoyaltyRevenueMember" name="NonCashRoyaltyRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_NoncashInterestExpenseOnLiability" name="NoncashInterestExpenseOnLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_NoncashRevenueRelatedToSaleOfFutureRoyalties" name="NoncashRevenueRelatedToSaleOfFutureRoyalties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_OpenMarketSaleAgreementMaximumAggregateOfferingPrice" name="OpenMarketSaleAgreementMaximumAggregateOfferingPrice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_OpenMarketSaleAgreementSalesCommissionPercentage" name="OpenMarketSaleAgreementSalesCommissionPercentage" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_OperatingLossCarryforwardCarriedForwardIndefinitely" name="OperatingLossCarryforwardCarriedForwardIndefinitely" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_OperatingLossCarryforwardsSubjectToExpiration" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="vxrt_OptionsAndRsuMember" name="OptionsAndRsuMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ProceedsFromIssuanceOfCommonStockNet" name="ProceedsFromIssuanceOfCommonStockNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ProceedsFromSaleOfFutureRoyaltiesNet" name="ProceedsFromSaleOfFutureRoyaltiesNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_RaCapitalHealthcareFund2024Member" name="RaCapitalHealthcareFund2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ReductionInWorkforcePercentage" name="ReductionInWorkforcePercentage" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_RegisteredDirectOfferingMember" name="RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_RevenueTextBlock" name="RevenueTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_RightOfUseForOfficeAndManufacturingFacilitiesWithInitialTermsExceedingOneYearMember" name="RightOfUseForOfficeAndManufacturingFacilitiesWithInitialTermsExceedingOneYearMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_RoyaltyInterestAdditionalRoyaltiesDueEachYear" name="RoyaltyInterestAdditionalRoyaltiesDueEachYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_RoyaltyInterestCovenantCumulativeRemainingShortfallAmount" name="RoyaltyInterestCovenantCumulativeRemainingShortfallAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_RoyaltyInterestCovenantShortfallInRoyaltyPayments" name="RoyaltyInterestCovenantShortfallInRoyaltyPayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="vxrt_RoyaltyInterestPercentageOfAdditionalRoyaltiesDueEachYear" name="RoyaltyInterestPercentageOfAdditionalRoyaltiesDueEachYear" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="vxrt_RoyaltyPaymentInterestFirstPeriodMember" name="RoyaltyPaymentInterestFirstPeriodMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_RoyaltyPaymentInterestSecondPeriodMember" name="RoyaltyPaymentInterestSecondPeriodMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_RoyaltyPercentage" name="RoyaltyPercentage" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_RoyaltyWithholdingTax" name="RoyaltyWithholdingTax" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ScheduleOfCommonStockReservedForIssuanceTableTextBlock" name="ScheduleOfCommonStockReservedForIssuanceTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_SecondSetOfWarrantsExpiringApril2024Member" name="SecondSetOfWarrantsExpiringApril2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_September2021AtmMember" name="September2021AtmMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_September2021LeaseForFacilityInSouthSanFranciscoMember" name="September2021LeaseForFacilityInSouthSanFranciscoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ShareBasedCompensationArrangementByShareBasedPaymentAwardCanceled" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCanceled" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeited" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeited" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantDecreaseFromGrants" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantDecreaseFromGrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_SouthSanFranciscoRealEstateMember" name="SouthSanFranciscoRealEstateMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrants" name="StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_StockIssuedDuringPeriodValueExerciseOfCommonStockWarrants" name="StockIssuedDuringPeriodValueExerciseOfCommonStockWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_The2019PlanMember" name="The2019PlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_The2022EsppMember" name="The2022EsppMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_The2023ShelfRegistrationMember" name="The2023ShelfRegistrationMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_The2024InducementAwardPlanMember" name="The2024InducementAwardPlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_TheSeptember2021AtmMember" name="TheSeptember2021AtmMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="vxrt_WarrantExercisePriceToBeEntitledToReceiveCashConsiderationFundamentalTransaction" name="WarrantExercisePriceToBeEntitledToReceiveCashConsiderationFundamentalTransaction" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="vxrt_WarrantsExpiringFebruary2025Member" name="WarrantsExpiringFebruary2025Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_WarrantsExpiringMarch2024Member" name="WarrantsExpiringMarch2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_WarrantsExpiringMarch2025Member" name="WarrantsExpiringMarch2025Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-10-stockholders-equity-shares-of-common-stock-reserved-for-issuance-details" name="statement-statement-note-10-stockholders-equity-shares-of-common-stock-reserved-for-issuance-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-10-stockholders-equity-summary-of-warrants-outstanding-details" name="statement-statement-note-10-stockholders-equity-summary-of-warrants-outstanding-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-10-stockholders-equity-tables" name="statement-statement-note-10-stockholders-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-11-equity-incentive-plans-assumptions-of-employee-purchase-plan-details" name="statement-statement-note-11-equity-incentive-plans-assumptions-of-employee-purchase-plan-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-11-equity-incentive-plans-assumptions-of-options-details" name="statement-statement-note-11-equity-incentive-plans-assumptions-of-options-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-11-equity-incentive-plans-summary-of-stock-option-transactions-details" name="statement-statement-note-11-equity-incentive-plans-summary-of-stock-option-transactions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-11-equity-incentive-plans-tables" name="statement-statement-note-11-equity-incentive-plans-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-11-equity-incentive-plans-total-stockbased-compensation-recognized-for-options-details" name="statement-statement-note-11-equity-incentive-plans-total-stockbased-compensation-recognized-for-options-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-13-income-taxes-components-of-deferred-tax-assets-details" name="statement-statement-note-13-income-taxes-components-of-deferred-tax-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-13-income-taxes-components-of-income-tax-expense-details" name="statement-statement-note-13-income-taxes-components-of-income-tax-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-13-income-taxes-reconciliation-of-effective-tax-rate-details" name="statement-statement-note-13-income-taxes-reconciliation-of-effective-tax-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-13-income-taxes-tables" name="statement-statement-note-13-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-13-income-taxes-unrecognized-tax-benefits-details" name="statement-statement-note-13-income-taxes-unrecognized-tax-benefits-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-14-net-loss-per-share-attributable-to-common-stockholders-calculation-of-basic-and-diluted-net-loss-income-per-share-details" name="statement-statement-note-14-net-loss-per-share-attributable-to-common-stockholders-calculation-of-basic-and-diluted-net-loss-income-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-14-net-loss-per-share-attributable-to-common-stockholders-summary-of-antidilutive-securities-details" name="statement-statement-note-14-net-loss-per-share-attributable-to-common-stockholders-summary-of-antidilutive-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-14-net-loss-per-share-tables" name="statement-statement-note-14-net-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-2-summary-of-significant-accounting-policies-estimated-useful-lives-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-estimated-useful-lives-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-2-summary-of-significant-accounting-policies-tables" name="statement-statement-note-2-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-3-business-combination-allocation-of-the-purchase-price-to-the-fair-value-of-the-respective-assets-and-liabilities-acquired-details" name="statement-statement-note-3-business-combination-allocation-of-the-purchase-price-to-the-fair-value-of-the-respective-assets-and-liabilities-acquired-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-3-business-combination-tables" name="statement-statement-note-3-business-combination-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-4-fair-value-of-financial-instruments-financial-assets-measured-on-a-recurring-basis-details" name="statement-statement-note-4-fair-value-of-financial-instruments-financial-assets-measured-on-a-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-4-fair-value-of-financial-instruments-tables" name="statement-statement-note-4-fair-value-of-financial-instruments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-accrued-liabilities-details" name="statement-statement-note-5-balance-sheet-components-accrued-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-cash-and-cash-equivalents-and-investments-details" name="statement-statement-note-5-balance-sheet-components-cash-and-cash-equivalents-and-investments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-estimated-future-amortization-expense-details" name="statement-statement-note-5-balance-sheet-components-estimated-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-intangible-assets-details" name="statement-statement-note-5-balance-sheet-components-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-property-and-equipment-net-details" name="statement-statement-note-5-balance-sheet-components-property-and-equipment-net-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-5-balance-sheet-components-tables" name="statement-statement-note-5-balance-sheet-components-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-7-liabilities-related-to-sale-of-future-royalties-deferred-revenue-activity-details" name="statement-statement-note-7-liabilities-related-to-sale-of-future-royalties-deferred-revenue-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-7-liabilities-related-to-sale-of-future-royalties-tables" name="statement-statement-note-7-liabilities-related-to-sale-of-future-royalties-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-8-leases-lease-liabilities-payment-obligations-details" name="statement-statement-note-8-leases-lease-liabilities-payment-obligations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-8-leases-operating-lease-expenses-details" name="statement-statement-note-8-leases-operating-lease-expenses-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-note-8-leases-tables" name="statement-statement-note-8-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="vxrt_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
