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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Segment Reporting (Q1)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <!--Parent Role: Risks and Liquidity (FY)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Summary of Significant Accounting Policies (FY)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <!--Parent Role: Cash, Cash Equivalents, and Marketable Securities (FY)-->
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        <!--Parent Role: Fair Value of Financial Instruments and Non-Financial Instruments (FY)-->
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <!--Parent Role: Fair Value of Financial Instruments and Non-Financial Instruments (FY)-->
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        <!--Parent Role: Property and Equipment, Net (FY)-->
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        <!--Parent Role: Property and Equipment, Net (FY)-->
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <!--Parent Role: Accrued Expenses and Other Current Liabilities (FY)-->
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://passagebio.com/role/GemmaLicenseAgreementFyDetails" id="GemmaLicenseAgreementFyDetails">
        <!--Parent Role: Gemma License Agreement (FY)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <!--Parent Role: Property and Equipment, Net (Q1)-->
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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  <xs:element name="NonRefundableUpfrontFeesPayablePerProductIndication" id="pasg_NonRefundableUpfrontFeesPayablePerProductIndication" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="EquityIncentivePlan2020Member" id="pasg_EquityIncentivePlan2020Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="DeferredProceedsReceivableFromSaleOfEquipmentInOtherCurrentAssets" id="pasg_DeferredProceedsReceivableFromSaleOfEquipmentInOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="RisksLiquidityAndGoingConcernAbstract" id="pasg_RisksLiquidityAndGoingConcernAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="InterimFinancialStatementsPolicyTextBlock" id="pasg_InterimFinancialStatementsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="OperatingLossCarryforwardSubjectToExpiration" id="pasg_OperatingLossCarryforwardSubjectToExpiration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="LocalTaxAuthoritiesMember" id="pasg_LocalTaxAuthoritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="StateTaxAuthorityMember" id="pasg_StateTaxAuthorityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="OrphanDrugMember" id="pasg_OrphanDrugMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="RemainingCapacityOfValueOfSharesAvailableToBeSold" id="pasg_RemainingCapacityOfValueOfSharesAvailableToBeSold" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="EarlyLeaseTerminationFee" id="pasg_EarlyLeaseTerminationFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" id="pasg_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="LeaseLiabilityForOperatingLeasePeriodDecreaseDueToLeaseTermination" id="pasg_LeaseLiabilityForOperatingLeasePeriodDecreaseDueToLeaseTermination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="RightOfUsePeriodDecreaseDueToLeaseTermination" id="pasg_RightOfUsePeriodDecreaseDueToLeaseTermination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="GainLossOnWriteOffOfOperatingLeases" id="pasg_GainLossOnWriteOffOfOperatingLeases" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="LicenseFeeDueAndReceivable" id="pasg_LicenseFeeDueAndReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="ProceedsFromShortTermLicenseFee" id="pasg_ProceedsFromShortTermLicenseFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="EstimatedSeveranceAndRelatedCosts" id="pasg_EstimatedSeveranceAndRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="RestructuringPlanReductionInWorkforcePercentage" id="pasg_RestructuringPlanReductionInWorkforcePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="PaymentOfLeaseTerminationFee" id="pasg_PaymentOfLeaseTerminationFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="MergerAgreementTerminationPaymentAmount" id="pasg_MergerAgreementTerminationPaymentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="MarketStreetLeaseAgreement2005Member" id="pasg_MarketStreetLeaseAgreement2005Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" id="pasg_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" id="pasg_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" />
  <xs:element name="DeferredTaxAssetsCollaborationAndLicenseAgreement" id="pasg_DeferredTaxAssetsCollaborationAndLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DeferredTaxAssetsDepreciationAndAmortization" id="pasg_DeferredTaxAssetsDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" id="pasg_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" />
  <xs:element name="DeferredTaxAssetsOperatingLeaseLiabilities" id="pasg_DeferredTaxAssetsOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" id="pasg_DeferredTaxAssetsCapitalizedResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilitiesAndOther" id="pasg_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilitiesAndOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
</xs:schema>
