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  <xs:element id="goss_NetOperatingLossesCarryforwardAvailableToOffsetFutureFederalTaxableIncomePercentage" abstract="false" name="NetOperatingLossesCarryforwardAvailableToOffsetFutureFederalTaxableIncomePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate" abstract="false" name="UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_DeferredTaxAssetsLeaseLiability" abstract="false" name="DeferredTaxAssetsLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_DeferredTaxLiabilitiesRightOfUseAsset" abstract="false" name="DeferredTaxLiabilitiesRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_StockholdersEquityDeficitTable" abstract="true" name="StockholdersEquityDeficitTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="goss_OfficerDirectorEmployeeOrConsultantMember" abstract="true" name="OfficerDirectorEmployeeOrConsultantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_ChiesiFarmaceuticiS.p.AAndChiesiUSAInc.Member" abstract="true" name="ChiesiFarmaceuticiS.p.AAndChiesiUSAInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_FounderSharesMember" abstract="true" name="FounderSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="goss_StockholdersEquityDeficitLineItems" abstract="true" name="StockholdersEquityDeficitLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="goss_CommonStockVotingRightsNumberOfVotesPerShare" abstract="false" name="CommonStockVotingRightsNumberOfVotesPerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="goss_CommonStockVestingPercentage" abstract="false" name="CommonStockVestingPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_CommonStockVestingPeriod" abstract="false" name="CommonStockVestingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_PercentageOfFullyDilutedShareCapital" abstract="false" name="PercentageOfFullyDilutedShareCapital" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_IncreasedInEquityCapitalAmount" abstract="false" name="IncreasedInEquityCapitalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="goss_IncrementalCommonSharesAttributableToRestrictedStockSubjectToVesting" abstract="false" name="IncrementalCommonSharesAttributableToRestrictedStockSubjectToVesting" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_CollaborationAgreementEquityOptionOwnedByCounterpartyPercentage" abstract="false" name="CollaborationAgreementEquityOptionOwnedByCounterpartyPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_CollaborationAgreementEquityOptionOwnedByCounterpartyTenderOfferOrExchangeOfferPercentageOfSharesOutstanding" abstract="false" name="CollaborationAgreementEquityOptionOwnedByCounterpartyTenderOfferOrExchangeOfferPercentageOfSharesOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_CollaborationAgreementEquityOptionOwnedByCounterpartyPurchasePricePercentageOfCommonStocksAveragePerSharePrice" abstract="false" name="CollaborationAgreementEquityOptionOwnedByCounterpartyPurchasePricePercentageOfCommonStocksAveragePerSharePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_CollaborationAgreementEquityOptionOwnedByCounterpartyPurchasePriceNumberOfTradingDays" abstract="false" name="CollaborationAgreementEquityOptionOwnedByCounterpartyPurchasePriceNumberOfTradingDays" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="goss_CollaborationAgreementEquityOptionOwnedByCounterpartyMinimumPurchasePrice" abstract="false" name="CollaborationAgreementEquityOptionOwnedByCounterpartyMinimumPurchasePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_TwoThousandTwentyThreeEquityInducementIncentivePlanMember" abstract="true" name="TwoThousandTwentyThreeEquityInducementIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_TwoThousandNineteenEquityIncentivePlanMember" abstract="true" name="TwoThousandNineteenEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_TwoThousandNineteenEmployeeStockPurchasePlanMember" abstract="true" name="TwoThousandNineteenEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_TwoThousandSeventeenEquityIncentivePlanMember" abstract="true" name="TwoThousandSeventeenEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_SharesReservedForIssuanceOnGrantingOfOutstandingAwards" abstract="false" name="SharesReservedForIssuanceOnGrantingOfOutstandingAwards" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalNumberOfSharesAuthorized" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalNumberOfSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesIssued" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesIssued" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="goss_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsThresholdConsecutiveDays" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsThresholdConsecutiveDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="goss_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsThresholdSharePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsThresholdSharePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="goss_ShareBasedPaymentArrangementOptionRequiredCancellationPercentage" abstract="false" name="ShareBasedPaymentArrangementOptionRequiredCancellationPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="goss_EmployeeStockPurchasePlanMember" abstract="true" name="EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_LeaseAgreementEnteredInJuly2024Member" abstract="true" name="LeaseAgreementEnteredInJuly2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_NonCancelableLeaseAgreementEnteredInAugust2018Member" abstract="true" name="NonCancelableLeaseAgreementEnteredInAugust2018Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_LeaseeOperatingLeaseLeasedArea" abstract="false" name="LeaseeOperatingLeaseLeasedArea" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
  <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_CommercialPlanningActivitiesMember" abstract="true" name="CommercialPlanningActivitiesMember" 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_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_USLicenseMember" abstract="true" name="USLicenseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="goss_ROWLicenseMember" abstract="true" name="ROWLicenseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ContractWithCustomerLiabilityUpfrontPaymentReceived" abstract="false" name="ContractWithCustomerLiabilityUpfrontPaymentReceived" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_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_FaheemHasnainMember" abstract="true" name="FaheemHasnainMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
