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  <xs:element id="goss_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="goss_ClassOfWarrantOrRightPremiumToTheReferencePricePercentage" abstract="false" name="ClassOfWarrantOrRightPremiumToTheReferencePricePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_StockIssuedDuringPeriodSharesWarrantExercised" abstract="false" name="StockIssuedDuringPeriodSharesWarrantExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_LeaseAgreementEnteredInJuly2024Member" abstract="true" name="LeaseAgreementEnteredInJuly2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="goss_LesseeOperatingLeaseBaseRent" abstract="false" name="LesseeOperatingLeaseBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_LesseeOperatingLeaseBaseRentAnnualIncreasePercentage" abstract="false" name="LesseeOperatingLeaseBaseRentAnnualIncreasePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_LesseeOperatingLeaseExtensionTerm" abstract="false" name="LesseeOperatingLeaseExtensionTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_LesseeOperatingLeaseTerminationFeeNumberOfMonthsOfBaseRent" abstract="false" name="LesseeOperatingLeaseTerminationFeeNumberOfMonthsOfBaseRent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="goss_LicensesOfIntellectualPropertyMember" abstract="true" name="LicensesOfIntellectualPropertyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_ResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" abstract="true" name="ResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PAHAndPHILDResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" abstract="true" name="PAHAndPHILDResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PAHAndPHILDCommercializationActivitiesMember" abstract="true" name="PAHAndPHILDCommercializationActivitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_NumberOfDistinctPerformanceObligations" abstract="false" name="NumberOfDistinctPerformanceObligations" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="goss_NumberOfLicensesGranted" abstract="false" name="NumberOfLicensesGranted" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="goss_RevenuePerformanceObligationCommercialEffortsContributionPercentage" abstract="false" name="RevenuePerformanceObligationCommercialEffortsContributionPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_RevenuePerformanceObligationCommercializationActivitiesPerformancePercentage" abstract="false" name="RevenuePerformanceObligationCommercializationActivitiesPerformancePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_RevenuePerformanceObligationUpfrontNonrefundableAmountReceived" abstract="false" name="RevenuePerformanceObligationUpfrontNonrefundableAmountReceived" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_RevenuePerformanceObligationRegulatoryMilestonesAmount" abstract="false" name="RevenuePerformanceObligationRegulatoryMilestonesAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_RevenuePerformanceObligationSalesMilestonesAmount" abstract="false" name="RevenuePerformanceObligationSalesMilestonesAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_RevenueLoyaltyReceivableExpirationPeriod" abstract="false" name="RevenueLoyaltyReceivableExpirationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_ContractWithCustomerLiabilityDevelopmentCost" abstract="false" name="ContractWithCustomerLiabilityDevelopmentCost" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_ContractWithCustomerLiabilityFairValueOfEquityOption" abstract="false" name="ContractWithCustomerLiabilityFairValueOfEquityOption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_ContractWithCustomerRevenueRecognitionPeriod" abstract="false" name="ContractWithCustomerRevenueRecognitionPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_AccountReceivablePaymentTerm" abstract="false" name="AccountReceivablePaymentTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_PAHResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" abstract="true" name="PAHResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PHILDResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" abstract="true" name="PHILDResearchAndDevelopmentServicesPerformanceObligationsSatisfiedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_ContractWithCustomerLiabilityRollforwardAbstract" abstract="true" name="ContractWithCustomerLiabilityRollforwardAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="goss_ContractWithCustomerLiabilityEffectOfChangeInExchangeRate" abstract="false" name="ContractWithCustomerLiabilityEffectOfChangeInExchangeRate" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_PAHResearchAndDevelopmentServicesExpensesSubjectToReimbursementMember" abstract="true" name="PAHResearchAndDevelopmentServicesExpensesSubjectToReimbursementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PHILDResearchAndDevelopmentServicesExpensesSubjectToReimbursementMember" abstract="true" name="PHILDResearchAndDevelopmentServicesExpensesSubjectToReimbursementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PAHCommercialExpensesSubjectToReimbursementMember" abstract="true" name="PAHCommercialExpensesSubjectToReimbursementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_PHILDCommercialExpensesSubjectToReimbursementMember" abstract="true" name="PHILDCommercialExpensesSubjectToReimbursementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_EffectsOfExchangeRateMember" abstract="true" name="EffectsOfExchangeRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_ReportingSegmentMember" abstract="true" name="ReportingSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_AnnualEffectiveTaxRatePercentage" abstract="false" name="AnnualEffectiveTaxRatePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_AssetAcquisitionConsiderationTransferredEquityInterestSharesIssuableNumberOfShares" abstract="false" name="AssetAcquisitionConsiderationTransferredEquityInterestSharesIssuableNumberOfShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_ResearchAndDevelopmentArrangementContractualObligationAmountCommitted" abstract="false" name="ResearchAndDevelopmentArrangementContractualObligationAmountCommitted" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_RightsReacquisitionAgreementReimbursementOfResearchAndDevelopmentExpense" abstract="false" name="RightsReacquisitionAgreementReimbursementOfResearchAndDevelopmentExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_FaheemHasnainMember" abstract="true" name="FaheemHasnainMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
