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  <xs:element id="akba_IncreaseDecreaseInDeferredTaxAssets" abstract="false" name="IncreaseDecreaseInDeferredTaxAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_EffectiveIncomeTaxReconciliationAlternativeMinimumTax" abstract="false" name="EffectiveIncomeTaxReconciliationAlternativeMinimumTax" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_ViforPharmaMember" abstract="true" name="ViforPharmaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_DebtInstrumentFirstQuarterlyPeriodicPaymentPeriodAxis" abstract="true" name="DebtInstrumentFirstQuarterlyPeriodicPaymentPeriodAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="akba_PotentialPaymentForAchievementOfSpecifiedDevelopmentAndRegulatoryMilestones" abstract="false" name="PotentialPaymentForAchievementOfSpecifiedDevelopmentAndRegulatoryMilestones" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_RoyaltyPaymentsDue" abstract="false" name="RoyaltyPaymentsDue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_PaymentForLicenseAgreementReimbursementOfCostsIncurred" abstract="false" name="PaymentForLicenseAgreementReimbursementOfCostsIncurred" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_DefinedContributionPlanEmployeesAgeToBeEligibleUnderPlan" abstract="false" name="DefinedContributionPlanEmployeesAgeToBeEligibleUnderPlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="akba_CommercialMilestonePaymentsMember" abstract="true" name="CommercialMilestonePaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_CollateralAgentPharmakonMember" abstract="true" name="CollateralAgentPharmakonMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_ContractWithCustomerLiabilityAdditions" abstract="false" name="ContractWithCustomerLiabilityAdditions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_ShareBasedPaymentArrangementTrancheTwoSecondAnniversaryAfterGrantDateSubjectedToIndividualContinuedServiceMember" abstract="true" name="ShareBasedPaymentArrangementTrancheTwoSecondAnniversaryAfterGrantDateSubjectedToIndividualContinuedServiceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailableForPurchase" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailableForPurchase" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="akba_TwoThousandAndFourteenPlansMember" abstract="true" name="TwoThousandAndFourteenPlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_QuarterlyFinancialInformationLineItems" abstract="true" name="QuarterlyFinancialInformationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="akba_CashCashEquivalentsAndShortTermInvestmentsAmortizedCost" abstract="false" name="CashCashEquivalentsAndShortTermInvestmentsAmortizedCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_LicenseExpense" abstract="false" name="LicenseExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_ExcessInventoryPurchaseCommitmentsExpenseReversal" abstract="false" name="ExcessInventoryPurchaseCommitmentsExpenseReversal" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_LongTermPurchaseCommitmentFixedPricePeriod" abstract="false" name="LongTermPurchaseCommitmentFixedPricePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="akba_ShareBasedCompensationArrangementBySharesBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValueRollforward" abstract="true" name="ShareBasedCompensationArrangementBySharesBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValueRollforward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="akba_DevelopmentMilestonesPaymentMember" abstract="true" name="DevelopmentMilestonesPaymentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_PercentageOfRemainingCreditableAmountAppliedToFuturePayments" abstract="false" name="PercentageOfRemainingCreditableAmountAppliedToFuturePayments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_ShareBasedCompensationArrangementByShareBasedPaymentAwardConvertedOutstandingAndUnexercisedOptionsToPurchase" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardConvertedOutstandingAndUnexercisedOptionsToPurchase" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="akba_DevelopmentAndCommercializeCollaborationAndLicenseAgreementMember" abstract="true" name="DevelopmentAndCommercializeCollaborationAndLicenseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_BusinessCombinationRiskAdjustedDiscountRatesUsedToCalculatePresentValueOfFutureExpectedCashInflowsOfIntangibleAssets" abstract="false" name="BusinessCombinationRiskAdjustedDiscountRatesUsedToCalculatePresentValueOfFutureExpectedCashInflowsOfIntangibleAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_CollaborativeArrangementPotentialMilestoneReceivable" abstract="false" name="CollaborativeArrangementPotentialMilestoneReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_NumberOfPerformanceObligations" abstract="false" name="NumberOfPerformanceObligations" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="akba_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherIntangibleAssets" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherIntangibleAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_CantorFitzgeraldAndCompanyMember" abstract="true" name="CantorFitzgeraldAndCompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_LineOfCreditTerminationFeePercentage" abstract="false" name="LineOfCreditTerminationFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_OperatingLeaseMonthlyRentExpense" abstract="false" name="OperatingLeaseMonthlyRentExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_CollaborationAgreementTerminationNoticePeriod" abstract="false" name="CollaborationAgreementTerminationNoticePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="akba_PerformanceBasedRestrictedStockUnitMember" abstract="true" name="PerformanceBasedRestrictedStockUnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_RegulatoryMilestonePaymentsMember" abstract="true" name="RegulatoryMilestonePaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_ComputerEquipmentAndSoftwareMember" abstract="true" name="ComputerEquipmentAndSoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_PaymentReceivedForLicenseAgreementReimbursementOfPreviouslyCostsIncurred" abstract="false" name="PaymentReceivedForLicenseAgreementReimbursementOfPreviouslyCostsIncurred" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_OperatingLeaseFreeMonthlyRentPeriod" abstract="false" name="OperatingLeaseFreeMonthlyRentPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="akba_RebatesFeesAndOtherDeductionsMember" abstract="true" name="RebatesFeesAndOtherDeductionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="akba_InducementAwardProgramMember" abstract="true" name="InducementAwardProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_BostonMember" abstract="true" name="BostonMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_FacilityFeePercentagePaidOnPrincipalAmount" abstract="false" name="FacilityFeePercentagePaidOnPrincipalAmount" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOne" abstract="false" name="DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_DebtInstrumentFloorRate" abstract="false" name="DebtInstrumentFloorRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="akba_AllocatedShareBasedCompensationGrantedExpense" abstract="false" name="AllocatedShareBasedCompensationGrantedExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_MitsubishiTanabePharmaCorporationMember" abstract="true" name="MitsubishiTanabePharmaCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_SupplyAgreementPatheonIncMember" abstract="true" name="SupplyAgreementPatheonIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="akba_CollaborativeArrangementRoyaltyAndMilestonePayableMaximum" abstract="false" name="CollaborativeArrangementRoyaltyAndMilestonePayableMaximum" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="akba_ScheduleOfBusinessAcquisitionsTransactionPriceTableTextBlock" abstract="false" name="ScheduleOfBusinessAcquisitionsTransactionPriceTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
</xs:schema>
