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<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2020-02-26T20:58:27.3767118+00:00 -->
<!-- Version            : 5.0.1.321 -->
<!-- Package ID         : d77a5d6b9c264504afcc485cff4f9ebb -->
<!-- Copyright (c) 2020 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="rgnx_ProceedsFromIssuancesOfCommonStockNetOfUnderwritingDiscountsAndCommissions" name="ProceedsFromIssuancesOfCommonStockNetOfUnderwritingDiscountsAndCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_NoncashOrPartNoncashAssetsAcquiredUnderFinancingObligation" name="NoncashOrPartNoncashAssetsAcquiredUnderFinancingObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_LicenseAgreementRevenueRecognitionTextBlock" name="LicenseAgreementRevenueRecognitionTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LicenseAgreementRevenueRecognitionAbstract" name="LicenseAgreementRevenueRecognitionAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NonMarketableEquitySecuritiesPolicyTextBlock" name="NonMarketableEquitySecuritiesPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock" name="ScheduleOfCashAndCashEquivalentsAndRestrictedCashTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ScheduleOfRevenueOrAccountsReceivableByMajorCustomersTableTextBlock" name="ScheduleOfRevenueOrAccountsReceivableByMajorCustomersTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ScheduleOfUsefulLivesOfAssetsTableTextBlock" name="ScheduleOfUsefulLivesOfAssetsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_SummaryOfLeaseCostsAndSupplementalCashFlowInformationOfOperatingLeasesTableTextBlock" name="SummaryOfLeaseCostsAndSupplementalCashFlowInformationOfOperatingLeasesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ScheduleOfLesseeOperatingLeaseWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRate" name="ScheduleOfLesseeOperatingLeaseWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRate" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TrusteesOfTheUniversityOfPennsylvaniaMember" name="TrusteesOfTheUniversityOfPennsylvaniaMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_GlaxoSmithKlineLLCMember" name="GlaxoSmithKlineLLCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_SummaryOfChangesInReceivablesAndContractAssetsAndContractLiabilitiesTableTextBlock" name="SummaryOfChangesInReceivablesAndContractAssetsAndContractLiabilitiesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ScheduleOfLicenseRevenueTableTextBlock" name="ScheduleOfLicenseRevenueTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TwoThousandFourteenAndTwoThousandFifteenEquityIncentivePlanMember" name="TwoThousandFourteenAndTwoThousandFifteenEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NineThousandEightHundredMedicalCenterDriveMember" name="NineThousandEightHundredMedicalCenterDriveMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_CustomerAMember" name="CustomerAMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_CustomerBMember" name="CustomerBMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_CustomerCMember" name="CustomerCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_CustomerDMember" name="CustomerDMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_ComputerEquipmentAndSoftwareMember" name="ComputerEquipmentAndSoftwareMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_DeferredRentLiabilitiesCurrentAndNoncurrent" name="DeferredRentLiabilitiesCurrentAndNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_PrepaidExpensesOtherCurrentAssetsAndOtherAssets" name="PrepaidExpensesOtherCurrentAssetsAndOtherAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_TaxCutsAndJobsActReclassificationFromAOCIToRetainedEarningsTaxEffect" name="TaxCutsAndJobsActReclassificationFromAOCIToRetainedEarningsTaxEffect" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AvailableForSaleDebtSecuritiesRemainingMaturitiesGreaterThanThreeYears" name="AvailableForSaleDebtSecuritiesRemainingMaturitiesGreaterThanThreeYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_NonMarketableEquitySecurities" name="NonMarketableEquitySecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_CashEquivalentsAndMarketableSecuritiesMember" name="CashEquivalentsAndMarketableSecuritiesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_RemeasurementsOrImpairmentLossesOnNonMarketableEquitySecurities" name="RemeasurementsOrImpairmentLossesOnNonMarketableEquitySecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_NonMarketableEquitySecuritiesCarryingValue" name="NonMarketableEquitySecuritiesCarryingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_LeaseExpirationTerm" name="LeaseExpirationTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TenantImprovementAllowanceToBeReceived" name="TenantImprovementAllowanceToBeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_MinimumRequiredLeaseTermToUseOptionalTerminationOfLease" name="MinimumRequiredLeaseTermToUseOptionalTerminationOfLease" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_PercentageOfEarlyTerminationFee" name="PercentageOfEarlyTerminationFee" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TermOfRequiredBaseRentToBePaidAsTerminationFee" name="TermOfRequiredBaseRentToBePaidAsTerminationFee" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LesseeOperatingLeasePeriodicPaymentTermAfterTheCommencement" name="LesseeOperatingLeasePeriodicPaymentTermAfterTheCommencement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LesseeOperatingLeaseLeaseNotYetCommencedAdditionalAreaLeased" name="LesseeOperatingLeaseLeaseNotYetCommencedAdditionalAreaLeased" type="num:areaItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LesseeOperatingLeaseFrequencyOfPeriodicPayment" name="LesseeOperatingLeaseFrequencyOfPeriodicPayment" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_NineThousandSevenHundredTwelveMedicalCenterDriveMember" name="NineThousandSevenHundredTwelveMedicalCenterDriveMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NineThousandSixHundredBlackwellRoadMember" name="NineThousandSixHundredBlackwellRoadMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_FourHundredMadisonLeaseMember" name="FourHundredMadisonLeaseMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_LeaseAmendmentMember" name="LeaseAmendmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_MarylandAndNewYorkMember" name="MarylandAndNewYorkMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_LeaseCommencedDate" name="LeaseCommencedDate" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_RequiredPeriodToTerminateLeaseAfterCommencementPeriod" name="RequiredPeriodToTerminateLeaseAfterCommencementPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OperatingLeaseCommencementYear" name="OperatingLeaseCommencementYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OperatingLeaseExpirationYear" name="OperatingLeaseExpirationYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OperatingLeaseExpirationYear1" name="OperatingLeaseExpirationYear1" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OtherPropertiesHeldUnderOperatingLeasesMember" name="OtherPropertiesHeldUnderOperatingLeasesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_OtherOperatingLeasesMember" name="OtherOperatingLeasesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_UpfrontFeePayable" name="UpfrontFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_UniversityOfPennsylvaniaMember" name="UniversityOfPennsylvaniaMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NeurimmuneMember" name="NeurimmuneMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_ClearsideBiomedicalIncMember" name="ClearsideBiomedicalIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_RelatedPartyTransactionExpensesRevenueFromTransactionsWithRelatedParty" name="RelatedPartyTransactionExpensesRevenueFromTransactionsWithRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_LicenseFeesMember" name="LicenseFeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_RoyaltiesOnNetSalesOfLicensedProductsMember" name="RoyaltiesOnNetSalesOfLicensedProductsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_OtherCostsOfRevenueMember" name="OtherCostsOfRevenueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_TotalCostOfRevenuesMember" name="TotalCostOfRevenuesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_MilestonePaymentObligation" name="MilestonePaymentObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_PeriodForSharingOfResearchAndDevelopmentCost" name="PeriodForSharingOfResearchAndDevelopmentCost" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_PercentageOfPartnershipInCollaboration" name="PercentageOfPartnershipInCollaboration" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_PaymentAgainstExcerciseOfLicenseOption" name="PaymentAgainstExcerciseOfLicenseOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_PublicOfferingMember" name="PublicOfferingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_EquityIncentivePlanMember" name="EquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NumberOfDevelopmentPartneredProductCandidates" name="NumberOfDevelopmentPartneredProductCandidates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="rgnx_NumberOfCommercialProductCandidates" name="NumberOfCommercialProductCandidates" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LicenseRevenueLineItems" name="LicenseRevenueLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_LicenseRevenueTable" name="LicenseRevenueTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NAVTechnologyPlatformMember" name="NAVTechnologyPlatformMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_ZolgensmaRoyaltiesMember" name="ZolgensmaRoyaltiesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_LicenseAgreementMember" name="LicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_MarchTwoZeroOneFourLicenseAgreementMember" name="MarchTwoZeroOneFourLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_AveXisIncorporationMember" name="AveXisIncorporationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_JanuaryTwoZeroOneEightAmendmentAgreementMember" name="JanuaryTwoZeroOneEightAmendmentAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_FirstAnniversaryMember" name="FirstAnniversaryMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_SecondAnniversaryMember" name="SecondAnniversaryMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_SalesBasedMilestonesMember" name="SalesBasedMilestonesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_JuneTwoThousandSeventeenLicenseAgreementMember" name="JuneTwoThousandSeventeenLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_AbeonaTherapeuticsIncorporationMember" name="AbeonaTherapeuticsIncorporationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandEighteenDueMember" name="NovemberTwoThousandEighteenDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandNineteenDueMember" name="NovemberTwoThousandNineteenDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandTwentyDueMember" name="NovemberTwoThousandTwentyDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandTwentyOneDueMember" name="NovemberTwoThousandTwentyOneDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandTwentyTwoDueMember" name="NovemberTwoThousandTwentyTwoDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandTwentyThreeDueMember" name="NovemberTwoThousandTwentyThreeDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandTwentyFourDueMember" name="NovemberTwoThousandTwentyFourDueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_AprilTwoThousandTwentyMember" name="AprilTwoThousandTwentyMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NovemberTwoThousandEighteenLicenseAgreementMember" name="NovemberTwoThousandEighteenLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_ThirdAnniversaryMember" name="ThirdAnniversaryMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponCommencementOfClinicalTrials" name="MilestoneFeePaymentsUponCommencementOfClinicalTrials" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponSubmissionOfRegulatoryApprovalFilings" name="MilestoneFeePaymentsUponSubmissionOfRegulatoryApprovalFilings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponApprovalOfCommercialProducts" name="MilestoneFeePaymentsUponApprovalOfCommercialProducts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponAchievementOfSpecifiedSalesTargets" name="MilestoneFeePaymentsUponAchievementOfSpecifiedSalesTargets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponSubmissionPreclinicalFilings" name="MilestoneFeePaymentsUponSubmissionPreclinicalFilings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_ReceivablesAndContractAssetsAbstract" name="ReceivablesAndContractAssetsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_DeductionsRelatedToAccountsReceivable" name="DeductionsRelatedToAccountsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AdditionsRelatedToAccountsReceivable" name="AdditionsRelatedToAccountsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeductionsRelatedToContractWithCustomerAsset" name="DeductionsRelatedToContractWithCustomerAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AdditionsRelatedToContractWithCustomerAssets" name="AdditionsRelatedToContractWithCustomerAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeductionsRelatedToContractWithCustomerLiability" name="DeductionsRelatedToContractWithCustomerLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AdditionsRelatedToContractWithCustomerLiability" name="AdditionsRelatedToContractWithCustomerLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_UpfrontLicenseFeePaid" name="UpfrontLicenseFeePaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_MilestoneFeePaymentsUponAchievementOfVariousDevelopmentAndCommercialization" name="MilestoneFeePaymentsUponAchievementOfVariousDevelopmentAndCommercialization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_LicenseAgreementPeriod" name="LicenseAgreementPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LicenseAgreementAmendmentDate" name="LicenseAgreementAmendmentDate" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_LicenseFees" name="LicenseFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_MilestonePayments" name="MilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_UnpaidMilestonePayments" name="UnpaidMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_TransactionPriceOfLicense" name="TransactionPriceOfLicense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_PaymentsForRemainingDevelopmentMilestones" name="PaymentsForRemainingDevelopmentMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_IncreaseInTransactionPriceOfLicense" name="IncreaseInTransactionPriceOfLicense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_SalesBasedMilestonePaymentExcludeTransactionPrice" name="SalesBasedMilestonePaymentExcludeTransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_ConsiderationPaymentDuePeriodOne" name="ConsiderationPaymentDuePeriodOne" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ConsiderationPaymentDuePeriodTwo" name="ConsiderationPaymentDuePeriodTwo" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_UpfrontAndAnnualLicenseFeeReceivable" name="UpfrontAndAnnualLicenseFeeReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_UpfrontAndAnnualPaymentsReceivableUponTerminationOfLicenseAgreementPriorToExpiration" name="UpfrontAndAnnualPaymentsReceivableUponTerminationOfLicenseAgreementPriorToExpiration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_SalesBasedMilestonePaymentsReceivable" name="SalesBasedMilestonePaymentsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_RemainingUnpaidPortionOfUpfrontAndAnnualFees" name="RemainingUnpaidPortionOfUpfrontAndAnnualFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_IncreaseInUpfrontAndAnnualLicenseFeeReceivable" name="IncreaseInUpfrontAndAnnualLicenseFeeReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_LicenseAgreementInitialContractTerm" name="LicenseAgreementInitialContractTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_UpfrontLicenseFeeReceived" name="UpfrontLicenseFeeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_LicenseAgreementFinancingTerm" name="LicenseAgreementFinancingTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ShareBasedCompensationArrangementIncreaseInNumberOfSharesReservedForIssuancePercentageUnderPlan" name="ShareBasedCompensationArrangementIncreaseInNumberOfSharesReservedForIssuancePercentageUnderPlan" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TwoThousandAndFifteenEquityIncentivePlanMember" name="TwoThousandAndFifteenEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_NonEmployeeStockOptionMember" name="NonEmployeeStockOptionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_TwoThousandFifteenEmployeeStockPurchasePlanMember" name="TwoThousandFifteenEmployeeStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_StockPlanExpirationDate" name="StockPlanExpirationDate" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMinimum" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMinimum" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TaxCutsAndJobsActOf2017LimitationOfNetOperatingLossDeductionsAsPercentageOfCurrentYearTaxableIncome" name="TaxCutsAndJobsActOf2017LimitationOfNetOperatingLossDeductionsAsPercentageOfCurrentYearTaxableIncome" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_IncomeTaxDisclosureLineItems" name="IncomeTaxDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_IncomeTaxDisclosureTable" name="IncomeTaxDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxAssetAndValuationAllowanceProvisionalIncomeTaxExpense" name="TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxAssetAndValuationAllowanceProvisionalIncomeTaxExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeferredTaxAssetsIncreaseInAssetValueUponConversion" name="DeferredTaxAssetsIncreaseInAssetValueUponConversion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsNonQualifiedShareBasedCompensationCost" name="DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsNonQualifiedShareBasedCompensationCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeferredTaxAssetsLeaseLiability" name="DeferredTaxAssetsLeaseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeferredTaxAssetsDepreciation" name="DeferredTaxAssetsDepreciation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="rgnx_DeferredTaxLiabilitiesRightOfUseAssets" name="DeferredTaxLiabilitiesRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_CumulativeLossPositionPeriod" name="CumulativeLossPositionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OperatingLossCarryforwardsExpirationYear" name="OperatingLossCarryforwardsExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_TaxCreditCarryforwardExpirationYear" name="TaxCreditCarryforwardExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_CumulativeChangesInOwnershipInterestPercentage" name="CumulativeChangesInOwnershipInterestPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="rgnx_OwnershipInterestChangePeriod" name="OwnershipInterestChangePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="rgnx_FOXKISERLimitedLiabilityPartnershipMember" name="FOXKISERLimitedLiabilityPartnershipMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="rgnx_AccruedExternalResearchAndDevelopmentExpenses" name="AccruedExternalResearchAndDevelopmentExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AccruedSublicenseFeesAndRoyaltiesOnReagentSales" name="AccruedSublicenseFeesAndRoyaltiesOnReagentSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AccruedExternalGeneralAndAdministrativeExpenses" name="AccruedExternalGeneralAndAdministrativeExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_AccruedPurchasesOfPropertyAndEquipment" name="AccruedPurchasesOfPropertyAndEquipment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="rgnx_CostOfGoodsAndServicesSoldNetOfGoodsCredit" name="CostOfGoodsAndServicesSoldNetOfGoodsCredit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
</xsd:schema>
