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  <xs:element id="syre_OtherCommitmentRoyaltyPercentage" abstract="false" name="OtherCommitmentRoyaltyPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_OtherCommitmentRightToTerminateAgreementPriorWrittenNoticePeriod" abstract="false" name="OtherCommitmentRightToTerminateAgreementPriorWrittenNoticePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="syre_OtherCommitmentRightToTerminateAgreementByCounterpartyMaterialBreachUncuredPeriod" abstract="false" name="OtherCommitmentRightToTerminateAgreementByCounterpartyMaterialBreachUncuredPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="syre_OtherCommitmentRightToTerminateAgreementByCounterpartyPaymentsNotReceivedPeriod" abstract="false" name="OtherCommitmentRightToTerminateAgreementByCounterpartyPaymentsNotReceivedPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="syre_TwoThousandAndSixteenEquityIncentivePlanMember" abstract="true" name="TwoThousandAndSixteenEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_TwoThousandAndFifteenEquityIncentivePlanMember" abstract="true" name="TwoThousandAndFifteenEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_TwoThousandAndEighteenEquityInducementPlanMember" abstract="true" name="TwoThousandAndEighteenEquityInducementPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_TwoThousandAndFifteenAndTwoThousandAndSixteenEquityIncentivePlanAndTwoThousandAndEighteenEquityInducementPlanMember" abstract="true" name="TwoThousandAndFifteenAndTwoThousandAndSixteenEquityIncentivePlanAndTwoThousandAndEighteenEquityInducementPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_SpyreEquityPlanMember" abstract="true" name="SpyreEquityPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_TwoThousandAndSixteenEmployeeStockPurchasePlanMember" abstract="true" name="TwoThousandAndSixteenEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_ServiceBasedAwardsMember" abstract="true" name="ServiceBasedAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_NonEmployeesMember" abstract="true" name="NonEmployeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" abstract="false" name="IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="syre_AnnualPercentageOfAdditionalSharesWhichEqualsToIssuedAndOutstandingShares" abstract="false" name="AnnualPercentageOfAdditionalSharesWhichEqualsToIssuedAndOutstandingShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_ShareBasedPaymentArrangementPlanTermsAnnualLimitForNonEmployeeDirectorCompensationNumberOfShares" abstract="false" name="ShareBasedPaymentArrangementPlanTermsAnnualLimitForNonEmployeeDirectorCompensationNumberOfShares" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="syre_ShareBasedPaymentArrangementPlanModificationAnnualLimitForNonEmployeeDirectorCompensationAmount" abstract="false" name="ShareBasedPaymentArrangementPlanModificationAnnualLimitForNonEmployeeDirectorCompensationAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_ShareBasedPaymentArrangementPlanModificationNonEmployeeDirectorCompensationAmount" abstract="false" name="ShareBasedPaymentArrangementPlanModificationNonEmployeeDirectorCompensationAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalNumberOfSharesAvailableForGrant" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalNumberOfSharesAvailableForGrant" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="syre_ClassOfWarrantOrRightAnnualGrantPercentageOfCommonStockOutstanding" abstract="false" name="ClassOfWarrantOrRightAnnualGrantPercentageOfCommonStockOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_ClassOfWarrantOrRightNumberOfSeparateGrants" abstract="false" name="ClassOfWarrantOrRightNumberOfSeparateGrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="syre_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumAnnualFairMarketValuePerEmployee" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumAnnualFairMarketValuePerEmployee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalAnnualPercentageIncrease" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalAnnualPercentageIncrease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_MaximumNumberOfSharesPurchasedUnderEmployeeStockPurchasePlan" abstract="false" name="MaximumNumberOfSharesPurchasedUnderEmployeeStockPurchasePlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="syre_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="syre_EmployeesMember" abstract="true" name="EmployeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_LegacyAegleaEmployeesAndDirectorsMember" abstract="true" name="LegacyAegleaEmployeesAndDirectorsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_RestructuringActivitiesMember" abstract="true" name="RestructuringActivitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationChangeInFairMarketValueOfContingentValueRightAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationChangeInFairMarketValueOfContingentValueRightAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationLimitationOnOfficersCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationLimitationOnOfficersCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationForwardContractLiabilityAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationForwardContractLiabilityAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationContingentValueAddedLiabilityAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationContingentValueAddedLiabilityAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_IncomeTaxReconciliationTaxCostCredit" abstract="false" name="IncomeTaxReconciliationTaxCostCredit" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationForeignJurisdictionEffectAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationForeignJurisdictionEffectAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationChangeInFairMarketValueOfContingentValueRightPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationChangeInFairMarketValueOfContingentValueRightPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_EffectiveIncomeTaxRateReconciliationLimitationOnOfficersCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationLimitationOnOfficersCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="syre_IncomeTaxesTable" abstract="true" name="IncomeTaxesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="syre_IncomeTaxesLineItems" abstract="true" name="IncomeTaxesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="syre_DeferredTaxAssetsCapitalizedResearchAndDevelopmentCosts" abstract="false" name="DeferredTaxAssetsCapitalizedResearchAndDevelopmentCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_OperatingLossCarryforwardsSubjectToExpiration" abstract="false" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_TaxCreditCarryforwardsSubjectToExpiration" abstract="false" name="TaxCreditCarryforwardsSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_IncreaseDecreaseInFairValueOfContingentValueRightLiability" abstract="false" name="IncreaseDecreaseInFairValueOfContingentValueRightLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="syre_ScottBurrowsMember" abstract="true" name="ScottBurrowsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_ScottBurrowsNovember2025PlanMember" abstract="true" name="ScottBurrowsNovember2025PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="syre_ScottBurrowsApril2024PlanMember" abstract="true" name="ScottBurrowsApril2024PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
