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  <element name="FirstTrancheMember" id="ttph_FirstTrancheMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InitialPublicOfferingsCompletionDate" id="ttph_InitialPublicOfferingsCompletionDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="JanuaryFirstTwoThousandTwelveToAprilThirtiethTwoThousandFifteenMember" id="ttph_JanuaryFirstTwoThousandTwelveToAprilThirtiethTwoThousandFifteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LoanAgreementNumberOfTranches" id="ttph_LoanAgreementNumberOfTranches" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtCurrentIncludingDebtDiscountAndIssuanceCosts" id="ttph_LongTermDebtCurrentIncludingDebtDiscountAndIssuanceCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtNonCurrentIncludingDebtDiscountAndIssuanceCosts" id="ttph_LongTermDebtNonCurrentIncludingDebtDiscountAndIssuanceCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MilestonePayments" id="ttph_MilestonePayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NationalInstitutesOfHealthNationalInstituteOfAllergyAndInfectiousDiseasesMember" id="ttph_NationalInstitutesOfHealthNationalInstituteOfAllergyAndInfectiousDiseasesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageThresholdOfOutstandingStockForDeterminingAvailabilityOfGrants" id="ttph_PercentageThresholdOfOutstandingStockForDeterminingAvailabilityOfGrants" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PhaseThreeClinicalTrialMember" id="ttph_PhaseThreeClinicalTrialMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PotentialFuturePaymentsForRegulatoryMilestones" id="ttph_PotentialFuturePaymentsForRegulatoryMilestones" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrepaidClinicalExpenses" id="ttph_PrepaidClinicalExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrepaidExpenseAndOtherCurrentAssetsDisclosureTextBlock" id="ttph_PrepaidExpenseAndOtherCurrentAssetsDisclosureTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrepaidManufacturingFeesCurrent" id="ttph_PrepaidManufacturingFeesCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReclassificationOfConvertiblePreferredStockWarrantsToCommonStockWarrants" id="ttph_ReclassificationOfConvertiblePreferredStockWarrantsToCommonStockWarrants" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReclassificationOfDeferredFinancingCostsToAdditionalPaidInCapital" id="ttph_ReclassificationOfDeferredFinancingCostsToAdditionalPaidInCapital" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RegulatoryAssetsAbstract" id="ttph_RegulatoryAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevisedContractReceivableDueInNextRollingTwelveMonths" id="ttph_RevisedContractReceivableDueInNextRollingTwelveMonths" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RevisedGrantsReceivable" id="ttph_RevisedGrantsReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfPreferredStockWarrantLiabilityTableTextBlock" id="ttph_ScheduleOfPreferredStockWarrantLiabilityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SecondTrancheMember" id="ttph_SecondTrancheMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeptemberFirstTwoThousandElevenToSeptemberThirtiethTwoThousandSixteenMember" id="ttph_SeptemberFirstTwoThousandElevenToSeptemberThirtiethTwoThousandSixteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" id="ttph_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIncentivePlanTwoThousandSixMember" id="ttph_StockIncentivePlanTwoThousandSixMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIncentivePlanTwoThousandThirteenMember" id="ttph_StockIncentivePlanTwoThousandThirteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubawardMember" id="ttph_SubawardMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubcontractMember" id="ttph_SubcontractMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesLineItems" id="ttph_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesTable" id="ttph_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SvbFinancialGroupMember" id="ttph_SvbFinancialGroupMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TermLoanMember" id="ttph_TermLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ThresholdOfSharesOutstandingForDeterminingAvailabilityOfGrants" id="ttph_ThresholdOfSharesOutstandingForDeterminingAvailabilityOfGrants" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTwelveTermLoanAMember" id="ttph_TwoThousandTwelveTermLoanAMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTwelveTermLoanBMember" id="ttph_TwoThousandTwelveTermLoanBMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnamortizedDebtIssuanceCostAndDebtDiscountCurrent" id="ttph_UnamortizedDebtIssuanceCostAndDebtDiscountCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnamortizedDebtIssuanceCostAndDebtDiscountNonCurrent" id="ttph_UnamortizedDebtIssuanceCostAndDebtDiscountNonCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UpfrontAndMilestonePayments" id="ttph_UpfrontAndMilestonePayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
</schema>


