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  <xsd:element name="SubleaseAgreementCMember" id="pasg_SubleaseAgreementCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AreaOfLandSubleasedPercentage" id="pasg_AreaOfLandSubleasedPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AreaSubleased" id="pasg_AreaSubleased" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="GeneticMedicinesSegmentMember" id="pasg_GeneticMedicinesSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentLaborAndRelatedExpenses" id="pasg_ResearchAndDevelopmentLaborAndRelatedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeLaborAndRelatedExpenses" id="pasg_GeneralAndAdministrativeLaborAndRelatedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromNonRefundableTransitionServicesPayments" id="pasg_ProceedsFromNonRefundableTransitionServicesPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LossContingencySharesAgreedByDefendant" id="pasg_LossContingencySharesAgreedByDefendant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DeferredTaxAssetsDepreciationAndAmortization" id="pasg_DeferredTaxAssetsDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentThirdPartyCosts" id="pasg_ResearchAndDevelopmentThirdPartyCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentShareBasedCompensation" id="pasg_ResearchAndDevelopmentShareBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentDepreciationAndAmortization" id="pasg_ResearchAndDevelopmentDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeThirdPartyCosts" id="pasg_GeneralAndAdministrativeThirdPartyCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeShareBasedCompensation" id="pasg_GeneralAndAdministrativeShareBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeDepreciationAndAmortization" id="pasg_GeneralAndAdministrativeDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ContingentProceedsFromUponCompletionOfCertainBusinessMilestones" id="pasg_ContingentProceedsFromUponCompletionOfCertainBusinessMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PayableDecreaseFromAmountsReceivedTransitionServicesPayments" id="pasg_PayableDecreaseFromAmountsReceivedTransitionServicesPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" id="pasg_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" id="pasg_EffectiveIncomeTaxRateReconciliationTaxCreditOrphanDrugPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="Rule10b51ArrangementModified" id="pasg_Rule10b51ArrangementModified" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NonRule10b51ArrangementModified" id="pasg_NonRule10b51ArrangementModified" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LaboratoryEquipmentAndCertainOtherAssetsMember" id="pasg_LaboratoryEquipmentAndCertainOtherAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EmployeeStockPurchasePlanThresholdNumberOfSharesThatCanBePurchased" id="pasg_EmployeeStockPurchasePlanThresholdNumberOfSharesThatCanBePurchased" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PropertyPlantAndEquipmentAndCertainOtherAssetsMember" id="pasg_PropertyPlantAndEquipmentAndCertainOtherAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShortTermLicenseFeeDueAndReceivable" id="pasg_ShortTermLicenseFeeDueAndReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LongTermLicenseFeeDueAndReceivable" id="pasg_LongTermLicenseFeeDueAndReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
</xsd:schema>
