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        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:linkbaseRef xlink:type="simple" xlink:href="mtva-20260630_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="mtva-20260630_cal.xml" xlink:title="Calculation Links, all" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="mtva-20260630_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="mtva-20260630_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:roleType roleURI="http://metaviatx.com/role/DisclosureStandardAndCustomAxisDomainDefaults" id="DisclosureStandardAndCustomAxisDomainDefaults">
        <link:definition>99900 - Disclosure - Standard And Custom Axis Domain Defaults</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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    </xsd:appinfo>
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  <xsd:import namespace="http://xbrl.sec.gov/ecd/2026" schemaLocation="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-roles-2026.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://fasb.org/us-gaap/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd" />
  <xsd:import namespace="http://fasb.org/srt/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd" />
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  <xsd:element name="MaximumAggregateOfferingPrice" id="mtva_MaximumAggregateOfferingPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PercentageOfSalesAgentCommission" id="mtva_PercentageOfSalesAgentCommission" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="StockIssuanceCostAtMarketOfferingAgreement" id="mtva_StockIssuanceCostAtMarketOfferingAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockIssuedDuringPeriodSharesWarrantsExercisedShares" id="mtva_StockIssuedDuringPeriodSharesWarrantsExercisedShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodNumberOfSharesReservedForFurtherIssuanceIncreaseAnnually" id="mtva_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodNumberOfSharesReservedForFurtherIssuanceIncreaseAnnually" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockPlan2019Member" id="mtva_StockPlan2019Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DongStMember" id="mtva_DongStMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ClassOfWarrantOrRightNumberOfWarrantsIssued" id="mtva_ClassOfWarrantOrRightNumberOfWarrantsIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ClassUnitsMember" id="mtva_ClassUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ClassBUnitsMember" id="mtva_ClassBUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfCommonStockIssuedPerUnit" id="mtva_NumberOfCommonStockIssuedPerUnit" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodValueCommonStockAndWarrants" id="mtva_StockIssuedDuringPeriodValueCommonStockAndWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesCommonStockAndWarrants" id="mtva_StockIssuedDuringPeriodSharesCommonStockAndWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="TwoThousandTwentyOnePlanMember" id="mtva_TwoThousandTwentyOnePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockPlan2022Member" id="mtva_StockPlan2022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SharedServicesAgreementMember" id="mtva_SharedServicesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PrepaidExpenseAndOtherCurrentAssetsTextBlock" id="mtva_PrepaidExpenseAndOtherCurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber" id="mtva_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedWeightedAverageGrantDateFairValue" id="mtva_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AccruedLiabilitiesClinicalTrialCurrent" id="mtva_AccruedLiabilitiesClinicalTrialCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AccruedExpensesAndOtherLiabilitiesCurrent" id="mtva_AccruedExpensesAndOtherLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PreFundedWarrantsMember" id="mtva_PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ThresholdPeriodFollowingPublicAnnouncementOfReceivingPositivePhase1MultipleAscendingDoseDataForExpiryOfWarrants" id="mtva_ThresholdPeriodFollowingPublicAnnouncementOfReceivingPositivePhase1MultipleAscendingDoseDataForExpiryOfWarrants" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockAndWarrantsIssuanceCosts" id="mtva_StockAndWarrantsIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockPlan20192022AndInducementPlanMember" id="mtva_StockPlan20192022AndInducementPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CurrentLiabilitiesTextBlock" id="mtva_CurrentLiabilitiesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SingleReportableSegmentMember" id="mtva_SingleReportableSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LaborAndRelatedExpenseResearchAndDevelopment" id="mtva_LaborAndRelatedExpenseResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ConsultingFeeResearchAndDevelopment" id="mtva_ConsultingFeeResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LegalAndProfessionalFees" id="mtva_LegalAndProfessionalFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ConsultingFeeGeneralAndAdministrative" id="mtva_ConsultingFeeGeneralAndAdministrative" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LaborAndRelatedExpenseGeneralAndAdministrative" id="mtva_LaborAndRelatedExpenseGeneralAndAdministrative" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromIssuanceOfCommonStockAndWarrants" id="mtva_ProceedsFromIssuanceOfCommonStockAndWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateFairValueOutstandingBalance" id="mtva_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateFairValueOutstandingBalance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateFairValueOutstanding" id="mtva_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateFairValueOutstanding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="November2022SeriesBMember" id="mtva_November2022SeriesBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExpenseFirstClinicalTrialProgram" id="mtva_ResearchAndDevelopmentExpenseFirstClinicalTrialProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseSecondClinicalTrialProgram" id="mtva_ResearchAndDevelopmentExpenseSecondClinicalTrialProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockAndPreFundedWarrantsIssuanceCosts" id="mtva_StockAndPreFundedWarrantsIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DeferredIssuanceCostsIncurredButNotYetPaid" id="mtva_DeferredIssuanceCostsIncurredButNotYetPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ProceedsFromIssuanceOfStockAndPrefundedWarrants" id="mtva_ProceedsFromIssuanceOfStockAndPrefundedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentsForPlacementAgentFees" id="mtva_PaymentsForPlacementAgentFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RelatedPartyExtendedPaymentLiability" id="mtva_RelatedPartyExtendedPaymentLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RelatedPartyAccruedInterestPayable" id="mtva_RelatedPartyAccruedInterestPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RelatedPartyClinicalTrialAccruedLiability" id="mtva_RelatedPartyClinicalTrialAccruedLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="WarrantsExercisePrice15919.20Member" id="mtva_WarrantsExercisePrice15919.20Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="November2022SeriesBWarrantExercisePrice0.00Member" id="mtva_November2022SeriesBWarrantExercisePrice0.00Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="June2024PlacementAgentWarrantExercisePrice54.0375Member" id="mtva_June2024PlacementAgentWarrantExercisePrice54.0375Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="June2024SeriesBWarrantExercisePrice43.23Member" id="mtva_June2024SeriesBWarrantExercisePrice43.23Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AtMarketOfferingAgreementMember" id="mtva_AtMarketOfferingAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PublicOffering2026Member" id="mtva_PublicOffering2026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WarrantLiabilitiesFairValueDisclosure" id="mtva_WarrantLiabilitiesFairValueDisclosure" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SeriesCWarrantMember" id="mtva_SeriesCWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SeriesDWarrantMember" id="mtva_SeriesDWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NonCashLeaseCreditCharge" id="mtva_NonCashLeaseCreditCharge" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfWarrantsIssuedPerUnit" id="mtva_NumberOfWarrantsIssuedPerUnit" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="RelatedPartyExtendedPaymentLiabilityPayableInThreeMonths" id="mtva_RelatedPartyExtendedPaymentLiabilityPayableInThreeMonths" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CommonStockCapitalReservedForFutureIssuance" id="mtva_CommonStockCapitalReservedForFutureIssuance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="January2026PreFundedWarrantExercisePrice0.0010Member" id="mtva_January2026PreFundedWarrantExercisePrice0.0010Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="January2026SeriesCWarrantExercisePrice3.1000Member" id="mtva_January2026SeriesCWarrantExercisePrice3.1000Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="January2026SeriesDWarrantExercisePrice3.1000Member" id="mtva_January2026SeriesDWarrantExercisePrice3.1000Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FinancialInstrumentsLiabilitiesAndEquityPolicyPolicyTextBlock" id="mtva_FinancialInstrumentsLiabilitiesAndEquityPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RelatedPartyExtendedPaymentLiabilityPayable" id="mtva_RelatedPartyExtendedPaymentLiabilityPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodValueCommonStockAndPreFundedWarrants" id="mtva_StockIssuedDuringPeriodValueCommonStockAndPreFundedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesCommonStockAndPreFundedWarrants" id="mtva_StockIssuedDuringPeriodSharesCommonStockAndPreFundedWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NonCashProfessionalServicesExpense" id="mtva_NonCashProfessionalServicesExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ScheduleOfWarrantExercisedTableTextBlock" id="mtva_ScheduleOfWarrantExercisedTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="FirstAmendmentToStockPlan2022Member" id="mtva_FirstAmendmentToStockPlan2022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IncreaseDecreaseInAccruedLiabilitiesClinicalTrialCurrent" id="mtva_IncreaseDecreaseInAccruedLiabilitiesClinicalTrialCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
</xsd:schema>
