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    <element id="GTBP_AmendedAdvisoryAgreementMember" name="AmendedAdvisoryAgreementMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ClinicalStageBiopharmaceuticalMember" name="ClinicalStageBiopharmaceuticalMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_WarrantLiabilityCurrent" name="WarrantLiabilityCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_LossOnInitialRecognitionOfGreenshoeRightsLiability" name="LossOnInitialRecognitionOfGreenshoeRightsLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_GainOnSettlementOfDebt" name="GainOnSettlementOfDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodValueExerciseOfWarrantsForCashNet" name="StockIssuedDuringPeriodValueExerciseOfWarrantsForCashNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodSharesExerciseOfWarrantsForCashNet" name="StockIssuedDuringPeriodSharesExerciseOfWarrantsForCashNet" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_DividendsPreferredStockShares" name="DividendsPreferredStockShares" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodValueExerciseOfWarrantsForCashAndInducementWarrantsNet" name="StockIssuedDuringPeriodValueExerciseOfWarrantsForCashAndInducementWarrantsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodSharesExerciseOfWarrantsForCashAndInducementWarrantsNet" name="StockIssuedDuringPeriodSharesExerciseOfWarrantsForCashAndInducementWarrantsNet" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodValueIssuanceAndExerciseOfPrefundedWarrantsForElocFee" name="StockIssuedDuringPeriodValueIssuanceAndExerciseOfPrefundedWarrantsForElocFee" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodSharesIssuanceAndExerciseOfPrefundedWarrantsForElocFee" name="StockIssuedDuringPeriodSharesIssuanceAndExerciseOfPrefundedWarrantsForElocFee" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodValueIssuanceOfPrefundedWarrantToSettleVendorPayable" name="StockIssuedDuringPeriodValueIssuanceOfPrefundedWarrantToSettleVendorPayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_FairValueOfVestedStockOptions" name="FairValueOfVestedStockOptions" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_IssuanceOfWarrantsForVrtWaiver" name="IssuanceOfWarrantsForVrtWaiver" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_FairValueOfVestedWarrantsIssuedInSeriesLConvertiblePreferredStockTransaction" name="FairValueOfVestedWarrantsIssuedInSeriesLConvertiblePreferredStockTransaction" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_FairValueOfPrefundedWarrantsIssuedForElocFee" name="FairValueOfPrefundedWarrantsIssuedForElocFee" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_FairValueOfPrefundedWarrantAndCommonStockToSettleVendorPayable" name="FairValueOfPrefundedWarrantAndCommonStockToSettleVendorPayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_DividendOnConvertiblePreferredStock" name="DividendOnConvertiblePreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_DisclosureCommonStockWarrantsAndOptionsAbstract" name="DisclosureCommonStockWarrantsAndOptionsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_CommonStockWarrantsAndOptionsTextBlock" name="CommonStockWarrantsAndOptionsTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ScheduleOfWarrantsOustandingAndExercisableTableTextBlock" name="ScheduleOfWarrantsOustandingAndExercisableTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_SummaryOfSignificantAccountingPoliciesDetailsNarrativeAbstract" name="SummaryOfSignificantAccountingPoliciesDetailsNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_SummaryOfSignificantAccountingPoliciesDetailsNarrativeTable" name="SummaryOfSignificantAccountingPoliciesDetailsNarrativeTable" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" />
    <element id="GTBP_SummaryOfSignificantAccountingPoliciesDetailsNarrativeLineItems" name="SummaryOfSignificantAccountingPoliciesDetailsNarrativeLineItems" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_WeightedAverageVolumePriceOfCommonStockPercentage" name="WeightedAverageVolumePriceOfCommonStockPercentage" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisableNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisableNumber" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_StockIssuedDuringPeriodSharesDividends" name="StockIssuedDuringPeriodSharesDividends" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsGrantedWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsGrantedWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantedPursuantToFullRatchetPriceProtection" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantedPursuantToFullRatchetPriceProtection" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsGrantedPursuantToFullRatchetPriceProtectionWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsGrantedPursuantToFullRatchetPriceProtectionWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsForfeituresAndExpirationsWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsForfeituresAndExpirationsWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisedWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisedWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisable" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercisable" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisableWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsExercisableWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_DisclosureCommonStockWarrantsAndOptionsTable" name="DisclosureCommonStockWarrantsAndOptionsTable" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" />
    <element id="GTBP_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonVestedInPeriodFairValue1" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonVestedInPeriodFairValue1" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_OutstandingCommitments" name="OutstandingCommitments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_ProceedsFromUpfrontAmount" name="ProceedsFromUpfrontAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyFeePercentage" name="RoyaltyFeePercentage" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_PerformanceMilestonePayments" name="PerformanceMilestonePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_SalesMilestonePayments" name="SalesMilestonePayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_GrossSales" name="GrossSales" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_SalesRevenue" name="SalesRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_CummulativeGrossSales" name="CummulativeGrossSales" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyExpenseYearOne" name="RoyaltyExpenseYearOne" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyExpenseYearTwoThroughFive" name="RoyaltyExpenseYearTwoThroughFive" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyExpenseYearAfterSix" name="RoyaltyExpenseYearAfterSix" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_UpfrontLicenseFee" name="UpfrontLicenseFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyExpenseYearOneThoughFour" name="RoyaltyExpenseYearOneThoughFour" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_RoyaltyExpenseYearAfterFive" name="RoyaltyExpenseYearAfterFive" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_MinimumBidPriceRequirementDescription" name="MinimumBidPriceRequirementDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_LossOnInitialRecognitionOfLiability" name="LossOnInitialRecognitionOfLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_SeriesL10PercentageConvertiblePreferredStockMember" name="SeriesL10PercentageConvertiblePreferredStockMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="GTBP_PreferredStockPurchasePrice" name="PreferredStockPurchasePrice" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
</schema>
