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  <xsd:element id="nxtc_OmnibusIncentive2019PlanMember" name="OmnibusIncentive2019PlanMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="nxtc_EmployeeStockPurchase2019PlanMember" name="EmployeeStockPurchase2019PlanMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="nxtc_ShareBasedCompensationArrangementIncreaseInSharesForIssuanceAsPercentageOfNumberOfCommonStockOutstanding" name="ShareBasedCompensationArrangementIncreaseInSharesForIssuanceAsPercentageOfNumberOfCommonStockOutstanding" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="nxtc_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="nxtc_OmnibusIncentive2015PlanAndEmployeeStockPurchase2019PlanMember" name="OmnibusIncentive2015PlanAndEmployeeStockPurchase2019PlanMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="nxtc_MarketableSecuritiesAndCashEquivalents" name="MarketableSecuritiesAndCashEquivalents" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="nxtc_ScheduleOfAvailableForSaleSecuritiesMaturitiesTableTextBlock" name="ScheduleOfAvailableForSaleSecuritiesMaturitiesTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="nxtc_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTaxAdjusted" name="OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTaxAdjusted" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element name="DepreciationDepletionAndAmortizationAndOther" id="nxtc_DepreciationDepletionAndAmortizationAndOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EarningsPerSharesBasicAndDilutedAbstract" id="nxtc_EarningsPerSharesBasicAndDilutedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EarningsPerSharesBasicAndDilutedOtherDisclosuresAbstract" id="nxtc_EarningsPerSharesBasicAndDilutedOtherDisclosuresAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NoncashOperatingLeaseExpense" id="nxtc_NoncashOperatingLeaseExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AccruedAndOtherLiabilitiesCurrent" id="nxtc_AccruedAndOtherLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInAccruedAndOtherCurrentLiabilities" id="nxtc_IncreaseDecreaseInAccruedAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CashAndCashEquivalentsAndMarketableSecuritiesAtCarryingValue" id="nxtc_CashAndCashEquivalentsAndMarketableSecuritiesAtCarryingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CollaborationAgreementsDisclosureAbstract" id="nxtc_CollaborationAgreementsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LegochemBiosciencesMember" id="nxtc_LegochemBiosciencesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MaximumNumberOfAntibodyDrugConjugatesToBeDeveloped" id="nxtc_MaximumNumberOfAntibodyDrugConjugatesToBeDeveloped" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CollaborationAgreementsCostSharingPercentage" id="nxtc_CollaborationAgreementsCostSharingPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="CollaborativeArrangementReductionInExpenseAmount" id="nxtc_CollaborativeArrangementReductionInExpenseAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CollaborationAgreementsAdditionalReceivableOnFinalizationOfCostSharingTerms" id="nxtc_CollaborationAgreementsAdditionalReceivableOnFinalizationOfCostSharingTerms" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SingleReportingSegmentMember" id="nxtc_SingleReportingSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExpenseEmployeeCosts" id="nxtc_ResearchAndDevelopmentExpenseEmployeeCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseClinicalProductCandidates" id="nxtc_ResearchAndDevelopmentExpenseClinicalProductCandidates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseNonclinicalProductCandidates" id="nxtc_ResearchAndDevelopmentExpenseNonclinicalProductCandidates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseDepreciation" id="nxtc_ResearchAndDevelopmentExpenseDepreciation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeExpenseEmployeeCosts" id="nxtc_GeneralAndAdministrativeExpenseEmployeeCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeExpenseProfessionalServices" id="nxtc_GeneralAndAdministrativeExpenseProfessionalServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GeneralAndAdministrativeExpenseInsurance" id="nxtc_GeneralAndAdministrativeExpenseInsurance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockIssuedDuringPeriodReverseStockSplitFractionalShares" id="nxtc_StockIssuedDuringPeriodReverseStockSplitFractionalShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementAbstract" id="nxtc_LicenseAgreementAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementTextBlock" id="nxtc_LicenseAgreementTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LicenseAgreementTable" id="nxtc_LicenseAgreementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseAgreementLineItems" id="nxtc_LicenseAgreementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UponInitiationOfFirstPhase2ClinicalTrialForSim0505Member" id="nxtc_UponInitiationOfFirstPhase2ClinicalTrialForSim0505Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UponAchievingDevelopmentAndRegulatoryMilestoneOfZaimingProductMember" id="nxtc_UponAchievingDevelopmentAndRegulatoryMilestoneOfZaimingProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UponAchievingDevelopmentAndRegulatoryMilestoneOfNextcureProductMember" id="nxtc_UponAchievingDevelopmentAndRegulatoryMilestoneOfNextcureProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UponAchievingCommercialSalesBasedMilestoneMember" id="nxtc_UponAchievingCommercialSalesBasedMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicensingAgreementConsiderationToAcquireRights" id="nxtc_LicensingAgreementConsiderationToAcquireRights" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicensingAgreementUpfrontCashPayment" id="nxtc_LicensingAgreementUpfrontCashPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicensingAgreementAmountPayable" id="nxtc_LicensingAgreementAmountPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CommonStockCapitalSharesValueReservedForFutureIssuance" id="nxtc_CommonStockCapitalSharesValueReservedForFutureIssuance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicensingAgreementMilestonePayments" id="nxtc_LicensingAgreementMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LicensingAgreementExpense" id="nxtc_LicensingAgreementExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="GoingConcernPolicyPolicyTextBlock" id="nxtc_GoingConcernPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CashAndCashEquivalentsAtCarryingValueDebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent" id="nxtc_CashAndCashEquivalentsAtCarryingValueDebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="UponInitiationOfFirstPhase1ClinicalTrialForSim0505Member" id="nxtc_UponInitiationOfFirstPhase1ClinicalTrialForSim0505Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIssuedDuringPeriodSharesExerciseOfPreFundedWarrants" id="nxtc_StockIssuedDuringPeriodSharesExerciseOfPreFundedWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodValueExerciseOfPreFundedWarrants" id="nxtc_StockIssuedDuringPeriodValueExerciseOfPreFundedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PurchasePricePerWarrant" id="nxtc_PurchasePricePerWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PreFundedWarrantsMember" id="nxtc_PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WainwrightAtmAgreementMember" id="nxtc_WainwrightAtmAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
