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  <element name="PeriodOneMember" id="galt_PeriodOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PeriodSevenMember" id="galt_PeriodSevenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PeriodSixMember" id="galt_PeriodSixMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PeriodThreeMember" id="galt_PeriodThreeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PeriodTwoMember" id="galt_PeriodTwoMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PostConversionDividendRightsIssued" id="galt_PostConversionDividendRightsIssued" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PostConversionRedemptionRightReturnOnInvestmentMultiplierAmount" id="galt_PostConversionRedemptionRightReturnOnInvestmentMultiplierAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PreferredStockStatedValuePerShare" id="galt_PreferredStockStatedValuePerShare" type="num:perShareItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrepaidExpensesAndOtherPolicyTextBlock" id="galt_PrepaidExpensesAndOtherPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrivatePlacementTwentySixteenMember" id="galt_PrivatePlacementTwentySixteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromIssuanceOfPreferredStockNetOfIssuanceCosts" id="galt_ProceedsFromIssuanceOfPreferredStockNetOfIssuanceCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromIssuanceOrSaleOfEquityGross" id="galt_ProceedsFromIssuanceOrSaleOfEquityGross" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromSubscriptionAdvances" id="galt_ProceedsFromSubscriptionAdvances" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReclassificationOfConvertiblePreferredStockToEquity" id="galt_ReclassificationOfConvertiblePreferredStockToEquity" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReconciliationOfStatutoryTaxRateLineItems" id="galt_ReconciliationOfStatutoryTaxRateLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReconciliationOfStatutoryTaxRateTable" id="galt_ReconciliationOfStatutoryTaxRateTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="RedemptionDateDescription" id="galt_RedemptionDateDescription" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RedemptionPeriod" id="galt_RedemptionPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ResearchAndDevelopmentCreditsExpirationYear" id="galt_ResearchAndDevelopmentCreditsExpirationYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SbhSciencesIncMember" id="galt_SbhSciencesIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScenarioOneMember" id="galt_ScenarioOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScenarioTwoMember" id="galt_ScenarioTwoMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedLiabilitiesLineItems" id="galt_ScheduleOfAccruedLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedLiabilitiesTable" id="galt_ScheduleOfAccruedLiabilitiesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfComputationOfBasicAndDilutedEarningsPerCommonShareLineItems" id="galt_ScheduleOfComputationOfBasicAndDilutedEarningsPerCommonShareLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfComputationOfBasicAndDilutedEarningsPerCommonShareTable" id="galt_ScheduleOfComputationOfBasicAndDilutedEarningsPerCommonShareTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfComputationOfBasicAndDilutedEarningsPerShareTableTextBlock" id="galt_ScheduleOfComputationOfBasicAndDilutedEarningsPerShareTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfEquityAndOtherInvestmentsTableTextBlock" id="galt_ScheduleOfEquityAndOtherInvestmentsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SecondPaymentMember" id="galt_SecondPaymentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeptemberThirtyTwentyZeroNineSeriesBTwoTransactionMember" id="galt_SeptemberThirtyTwentyZeroNineSeriesBTwoTransactionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeptemberTwentyNineTwentySixteenSeriesBThreeTransactionMember" id="galt_SeptemberTwentyNineTwentySixteenSeriesBThreeTransactionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeptemberTwentyTwoTwentySixteenSeriesBThreeTransactionMember" id="galt_SeptemberTwentyTwoTwentySixteenSeriesBThreeTransactionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAAndBWarrantsMember" id="galt_SeriesAAndBWarrantsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAConvertiblePreferredStockMember" id="galt_SeriesAConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAOnePreferredStockMember" id="galt_SeriesAOnePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAOneWarrantMember" id="galt_SeriesAOneWarrantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesATwoWarrantMember" id="galt_SeriesATwoWarrantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBDirectorsMember" id="galt_SeriesBDirectorsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBNomineesMember" id="galt_SeriesBNomineesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBOneConvertiblePreferredStockMember" id="galt_SeriesBOneConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBOnePreferredStockMember" id="galt_SeriesBOnePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBOneRedeemableConvertiblePreferredStockMember" id="galt_SeriesBOneRedeemableConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBOneRedeemablePreferredStockMember" id="galt_SeriesBOneRedeemablePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBThreeConvertiblePreferredStockMember" id="galt_SeriesBThreeConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBthreePreferredStockMember" id="galt_SeriesBthreePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBTwoConvertiblePreferredStockMember" id="galt_SeriesBTwoConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBTwoPreferredStockMember" id="galt_SeriesBTwoPreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBTwoRedeemableConvertiblePreferredStockMember" id="galt_SeriesBTwoRedeemableConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBTwoRedeemablePreferredStockMember" id="galt_SeriesBTwoRedeemablePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesCConvertiblePreferredStockMember" id="galt_SeriesCConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsGrantsInPeriod" id="galt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsGrantsInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCanceledInPeriod" id="galt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCanceledInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfNonEmployeeDirectorsGrantedShares" id="galt_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfNonEmployeeDirectorsGrantedShares" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" id="galt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" id="galt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationCostRecognitionDateLatest" id="galt_ShareBasedCompensationCostRecognitionDateLatest" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareConversionRatio" id="galt_ShareConversionRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesLineItems" id="galt_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesTable" id="galt_SignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="StockAndWarrantsIssuedDuringPeriodSharesNewIssues" id="galt_StockAndWarrantsIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockAndWarrantsIssuedDuringPeriodValueNewIssues" id="galt_StockAndWarrantsIssuedDuringPeriodValueNewIssues" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockBThreeConvertiblePreferredStockMember" id="galt_StockBThreeConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuableShares" id="galt_StockIssuableShares" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuableValue" id="galt_StockIssuableValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodSharesNewIssuesForDirectors" id="galt_StockIssuedDuringPeriodSharesNewIssuesForDirectors" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueNewIssuesForDirectors" id="galt_StockIssuedDuringPeriodValueNewIssuesForDirectors" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockOptionsExercised" id="galt_StockOptionsExercised" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockWarrantsTextBlock" id="galt_StockWarrantsTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SupplementalDividendsOnConvertiblePreferredStock" id="galt_SupplementalDividendsOnConvertiblePreferredStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TerminationNoticePeriod" id="galt_TerminationNoticePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandFourteenAtMarketSalesAgreementMember" id="galt_TwoThousandFourteenAtMarketSalesAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UncategorizedAbstract" id="galt_UncategorizedAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedCapitalStockParValue" id="galt_UndesignatedCapitalStockParValue" type="num:perShareItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedCapitalStockSharesAuthorized" id="galt_UndesignatedCapitalStockSharesAuthorized" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedCapitalStockSharesAuthorizedButUnissued" id="galt_UndesignatedCapitalStockSharesAuthorizedButUnissued" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedCapitalStockSharesOutstanding" id="galt_UndesignatedCapitalStockSharesOutstanding" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedCapitalStockValue" id="galt_UndesignatedCapitalStockValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitsIssuedDuringPeriodUnitsNewIssues" id="galt_UnitsIssuedDuringPeriodUnitsNewIssues" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantExpirationDate" id="galt_WarrantExpirationDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantFourteenMember" id="galt_WarrantFourteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantIssueDate" id="galt_WarrantIssueDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantIssuedToPurchaseCommonStock" id="galt_WarrantIssuedToPurchaseCommonStock" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsExpirationDate" id="galt_WarrantsExpirationDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>




