REGENXBIO Inc. 10-K

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the audited financial statements and the notes thereto included elsewhere in this Annual Report on Form 10-K. In addition, you should read the “Risk Factors” and “Information Regarding Forward-Looking Statements” sections of this Annual Report on Form 10-K for a discussion of important factors that could cause actual results to differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. For a full discussion and analysis of financial condition and results of operations for the year ended December 31, 2024, including a year-over-year comparison to the year ended December 31, 2023, please read the “Management's Discussion and Analysis of Financial Condition and Results of Operations” section of our Annual Report on Form 10-K for the year ended December 31, 2024, which we filed with the SEC on March 13, 2025. Overview We are a leading clinical-stage biotechnology company seeking to improve lives through the curative potential of gene therapy. Our investigational gene therapies are designed to deliver functional genes to address genetic defects in cells, enabling the production of therapeutic proteins or antibodies that are intended to impact disease. Through a single administration, gene therapy could potentially alter the course of disease significantly and deliver improved patient outcomes with long-lasting effects. Overview of Product Candidates We have developed a broad pipeline of gene therapy programs using our proprietary adeno-associated virus (AAV) gene therapy delivery platform (NAV Technology Platform) as a one-time treatment to address an array of diseases. Our lead programs and product candidates are described below: • ABBV-RGX-314: We are developing ABBV-RGX-314 (surabgene lomparvovec, sura-vec) in collaboration with AbbVie as a potential one-time treatment for chronic retinal conditions that cause total or partial vision loss, including wet age-related macular degeneration (wet AMD) and diabetic retinopathy (DR). ABBV-RGX-314 is currently being evaluated in multiple clinical trials, including two pivotal trials (ATMOSPHERE and ASCENT), one Phase II bridging study, one long-term follow-up study and a fellow eye sub-study in patients with wet AMD, all utilizing subretinal delivery. Additionally, two Phase II clinical trials in patients with wet AMD (AAVIATE) and DR (ALTITUDE) are ongoing along with two corresponding long-term follow-up studies, all utilizing in-office suprachoroidal delivery. Within the Phase II study in DR, we are also evaluating ABBV-RGX-314 in diabetic macular edema (DME). Additionally, we are planning a Phase IIb/III program in DR and expect to dose the first patient in a two-part Phase IIb/III study (NAAVIGATE) in the second quarter of 2026. ABBV-RGX-314 uses the NAV ® AAV8 vector to deliver a gene encoding a therapeutic antibody fragment to inhibit vascular endothelial growth factor (VEGF). We have licensed certain exclusive rights to the SCS Microinjector ® from Clearside Biomedical, Inc. (Clearside) to deliver gene therapy treatments to the suprachoroidal space of the eye. Wet AMD Subretinal Delivery Enrollment in the ATMOSPHERE ® and ASCENT ® pivotal trials for the treatment of patients with wet AMD using subretinal delivery was completed in October 2025. These trials are expected to support global regulatory submissions with the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Topline data from these trials are expected to be shared in the fourth quarter of 2026 in partnership with AbbVie. Suprachoroidal Delivery The AAVIATE ® trial is a multi-center, open label, randomized, controlled, dose-escalation Phase II trial to evaluate the efficacy, safety and tolerability of suprachoroidal delivery of ABBV-RGX-314 for the treatment of wet AMD. Based on the favorable safety profile observed as of July 29, 2024, the Phase II AAVIATE trial enrolled a cohort to evaluate ABBV-RGX-314 at dose level 4 (1.5x10e12 GC/eye). Patients in this cohort received short course prophylactic steroid eye drops. 72 Table of Contents DR and DME The ALTITUDE ® trial is a multi-center, open label, randomized, controlled, dose-escalation Phase II trial to evaluate the efficacy, safety and tolerability of ABBV-RGX-314 using suprachoroidal delivery for the treatment of DR. In November 2023, we announced data showing ABBV-RGX-314 was well tolerated at dose levels 1 and 2 and positive signals of efficacy, including 20.8% of patients exhibiting > 2-step Diabetic Retinopathy Severity Scale (DRSS) improvement without additional DR treatment at one year. In August 2025, we and AbbVie executed an amendment to our collaboration agreement and announced plans to initiate a pivotal program consisting of a Phase IIb/III trial (NAAVIGATE) as well as a second Phase III trial. NAAVIGATE is a Phase IIb/III multicenter, randomized, masked, sham-controlled study to evaluate the safety and efficacy of sura-vec in subjects with non-proliferative DR (NPDR) without center-involved diabetic macular edema (CI-DME). The primary endpoint is > 2-step improvement on the diabetic retinopathy severity scale (DRSS) at one year. Following an interim analysis, REGENXBIO and AbbVie will initiate a Phase III expansion, which will include two Phase III trials, including a U.S. trial and a parallel global trial, led by AbbVie. We expect to dose the first patient in NAAVIGATE in the second quarter of 2026. The ALTITUDE trial includes a new cohort of patients with center-involved DME evaluating ABBV-RGX-314 at dose level 4. Enrollment completed in this cohort in June 2025. DME is a vision-threatening complication of DR; an estimated 34 million people globally have DME. Patients received a one-time, in-office injection of ABBV-RGX-314 at dose level 4 (1.5x10e12 GC/eye) with short course prophylactic steroid eye drops. • RGX-202: We are developing RGX-202 as an investigational AAV therapeutic for the treatment of Duchenne muscular dystrophy (Duchenne), using the NAV AAV8 vector to deliver a transgene for a novel microdystrophin that includes the functional elements of the C-Terminal domain as well as a muscle-specific promoter to support a targeted therapy for improved resistance to muscle damage associated with Duchenne. Other differentiating elements of RGX-202 include the proactive immune suppression regimen and in-house, state-of-the-art manufacturing that has demonstrated leading purity levels in Duchenne (>80% full capsids). AFFINITY DUCHENNE ® is a multicenter, open-label Phase I/II/III trial to evaluate the safety, tolerability and clinical efficacy of a one-time intravenous dose of RGX-202 in patients with Duchenne aged one and older. The initiation of the pivotal study was designed to enroll approximately 30 patients in the U.S. and Canada. In October 2025, we announced that enrollment in the AFFINITY DUCHENNE pivotal trial had completed and that we continue to enroll participants in the planned confirmatory trial. We expect to share topline data in the early second quarter of 2026 and request a pre-Biologics License Application (BLA) meeting with the FDA in mid-2026. We began manufacturing the first batches of RGX-202 intended for commercial supply at our Manufacturing Innovation Center and completed the Process Performance Qualification (PPQ) campaign in the fourth quarter of 2025. Additional regulatory interactions with the FDA and the EMA are planned for 1H 2026. We are also recruiting patients in the AFFINITY BEYOND ® trial, an observational screening study. The primary objective is to evaluate the prevalence of AAV8 antibodies in patients with Duchenne up to 12 years of age. Information collected in this study may be used to identify potential participants for the AFFINITY DUCHENNE trial and potential future trials of RGX-202. • RGX-121: We are developing RGX-121 (clemidsogene lanparvovec) in collaboration with Nippon Shinyaku in the United States and certain countries in Asia as an investigational one-time AAV therapeutic for the treatment of Mucopolysaccharidosis Type II (MPS II), also known as Hunter syndrome, using the NAV AAV9 vector to deliver the gene that encodes the iduronate-2-sulfatase enzyme. A BLA for RGX-121 seeking accelerated approval was submitted to the FDA in March 2025. The FDA subsequently granted priority review of the BLA and successfully completed mid-cycle meeting, Pre-license inspection (PLI) and Bioresearch monitoring information (BIMO) inspections. The PLI and BIMO inspections were completed with no observations. In August 2025, we announced that the FDA review timeline had been extended following submission of 12-month clinical data for all patients in the pivotal study of RGX-121 (n=13) in response to an FDA information request. The Prescription Drug User Fee Act (PDUFA) goal date was extended from November 9, 2025 to February 8, 2026. The longer-term data submitted to the FDA were presented at the International Congress of Inborn Errors of Metabolism (ICIEM) in September 2025. These results showed that in the pivotal phase of the CAMPSIITE trial (n=13), participants through one year sustained an 82% median reduction of cerebrospinal fluid (CSF) levels of HS D2S6. These longer-term data were consistent with previously reported topline pivotal results from the CAMPSIITE trial. 73 Table of Contents In January 2026, we announced that the FDA placed the RGX-121 program on clinical hold in relation to a serious adverse event in a patient treated in the Phase I/II trial of RGX-111. The FDA cited the similarities in products, study populations, and shared risk between the clinical studies. In February 2026, we announced that the FDA issued a Complete Response Letter (CRL) for the RGX-121 BLA. The FDA stated in the CRL that it had agreed to the study protocol in principle and outlined several reasons for not approving the gene therapy, including uncertainty regarding the study eligibility criteria to adequately define a population with neuronopathic disease (vs. attenuated disease), the comparability of the natural history external control to the study population, and the appropriateness of CSF HS D2S6 as a surrogate endpoint reasonably likely to predict clinical benefit. The CRL lists several potential paths forward, including a new study, treating additional patients and conducting longer-term follow up, and using an untreated control arm. Throughout active discussions during the BLA process, we believed we had addressed the points raised in the CRL through the submission of additional data and responses to numerous information requests. The FDA did not agree the data set provided substantial evidence of effectiveness to support approval of RGX-121 for the treatment of MPS II. We plan to request a Type A meeting with the FDA. As of March 2026, we plan to work with the FDA to address the clinical hold and CRL, and discuss potential paths forward for the program, Potential approval of the BLA for RGX-121 could result in receipt of a Rare Pediatric Disease Priority Review Voucher (PRV), assuming the statutory criteria are met. If approved, RGX-121 would be the first approved gene therapy and one-time treatment for MPS II. • RGX-111: We are developing RGX-111 in collaboration with Nippon Shinyaku in the United States and certain countries in Asia as an investigational one-time AAV therapeutic for the treatment of Mucopolysaccharidosis Type I (MPS I), also known as Hurler syndrome, using the NAV AAV9 vector to deliver the IDUA gene. In November 2023, future development of RGX-111 was halted as a result of a strategic pipeline prioritization and corporate restructuring. Prior to that announcement, RGX-111 demonstrated to be well tolerated and indicated encouraging biomarker and neurodevelopmental results in a Phase I/II study. Efforts to continue development of RGX-111 as part of the strategic partnership with Nippon Shinyaku are ongoing. In January 2026, we announced that the FDA placed the RGX-111 program on clinical hold following preliminary analysis of a single case of neoplasm (intraventricular CNS tumor) in a participant treated in the Phase I/II study. The case was identified during a routine brain MRI of an asymptomatic five-year-old participant who received intracisternal RGX-111 four years prior. Preliminary genetic analysis of the resected tumor detected an AAV vector genome integration event associated with overexpression of a proto-oncogene (PLAG1), which is known to be susceptible to chromosomal rearrangements. Final analysis of the resected tumor was conducted by an independent third-party lab, and, as previously reported, detected an AAV vector genome integration event associated with overexpression of a PLAG1. Clonal integration of AAV vector elements into the PLAG1 gene was detected in the tumor tissue. Analyses supported classification as a PLAG1‑family neuroepithelial tumor and are consistent with the hypothesis that AAV vector integration at the PLAG1 site contributed to tumor formation. Of note, this participant had a background of factors that could have contributed to risk of oncogenic transformation. This child underwent unsuccessful stem cell transplant at 4 months of age, with loss of donor chimerism, and he received chemotherapeutics that may have contributed to DNA damage. The report concludes, based on formal neuropsychologic testing and developmental pediatrician assessment, that the patient’s neurocognitive development is above average, which indicates mitigation of MPS I disease, and the patient continues to do well. We anticipate the analysis will be published in a peer-reviewed journal this year. AbbVie Collaboration for ABBV-RGX-314 In September 2021, we entered into a collaboration and license agreement with AbbVie Global Enterprises Ltd. (AbbVie), a subsidiary of AbbVie Inc., to jointly develop and commercialize ABBV-RGX-314 (as amended, the AbbVie Collaboration Agreement). Pursuant to the AbbVie Collaboration Agreement, both we and AbbVie are active participants in the development of ABBV-RGX-314 and development expenses are shared between the parties in accordance with the agreement. The Company will lead the manufacturing of ABBV-RGX-314 for clinical development and U.S. commercial supply, and AbbVie will lead the global commercialization of ABBV-RGX-314. We received an up-front fee of $370.0 million from AbbVie upon the effective date of the AbbVie Collaboration Agreement in November 2021, and we are eligible to receive up to $1.38 billion from AbbVie upon the achievement of specified development and sales-based milestones. Additionally, the parties will share equally in the net profits and net losses associated with the commercialization of ABBV-RGX-314 in the United States, and we are eligible to receive tiered royalties on net sales by AbbVie of ABBV-RGX-314 outside the United States. For additional information regarding the AbbVie Collaboration Agreement, please refer to Note 10, “License and Collaboration Agreements—AbbVie Collaboration and License Agreement” to the accompanying audited consolidated financial statements. 74 Table of Contents In August 2025, we and AbbVie entered into an amendment to the AbbVie Collaboration Agreement which modified the development plan and milestone payment structure for the ABBV-RGX-314 DR program. Under the amendment, we will conduct the first registration enabling trial for DR suprachoroidal (SCS) treatment as a combined Phase IIb/III trial (NAAVIGATE) which will be performed in two parts (Part 1 and Part 2), and AbbVie will conduct the second registration enabling trial as a separate, standalone Phase III trial. In lieu of the $200.0 million milestone due to us under the original AbbVie Collaboration Agreement upon first patient dosed in the first registration enabling trial for DR SCS treatment, AbbVie will pay us $100.0 million upon first patient dosed in the NAAVIGATE trial and an additional $100.0 million upon first patient dosed in the subsequent Phase III trial. Also pursuant to the amendment, AbbVie will lead a new Phase III randomized controlled study (ACHIEVE) to assess the injection burden, adverse events, change in disease activity, and long-term preservation of visual acuity of ABBV-RGX-314 in adult participants with neovascular AMD. We will be responsible for our development expenses to conduct Part 1 of the NAAVIGATE trial and the parties will share the development expenses related to Part 2 of the NAAVIGATE trial and the subsequent Phase III trial for DR in accordance with the existing terms of the AbbVie Collaboration Agreement. AbbVie will be responsible for all development expenses related to the ACHIEVE study. Nippon Shinyaku Collaboration for RGX-121 and RGX-111 In January 2025, we entered into a collaboration and license agreement with Nippon Shinyaku Co., Ltd. (Nippon Shinyaku) for the development and commercialization of RGX-121 and RGX-111 (the Nippon Shinyaku Collaboration Agreement). Pursuant to the Nippon Shinyaku Collaboration Agreement, we are responsible for the development of RGX-121 and RGX-111 in the United States, and Nippon Shinyaku is responsible for development in licensed territories outside the United States. We are responsible for the manufacturing of RGX-121 and RGX-111 for clinical development and commercial supply, and manufacturing expenses will be allocated between the parties in accordance with the terms of the Nippon Shinyaku Collaboration Agreement. Nippon Shinyaku is responsible, at its sole cost, for the commercialization of RGX-121 and RGX-111 in the licensed territories. Under the terms of the Nippon Shinyaku Collaboration Agreement, we received an up-front payment of $110.0 million from Nippon Shinyaku following the effective date of the agreement in March 2025 and are eligible to receive up to $700.0 million from Nippon Shinyaku upon the achievement of specified development and sales-based milestones. We are also eligible to receive double-digit royalties on net sales of RGX-121 and RGX-111 by Nippon Shinyaku, subject to specified offsets and reductions. We retain all rights to, and any proceeds related to the sale of, any priority review vouchers that may be issued upon the potential approvals of RGX-121 and RGX-111. We recognized $84.7 million of revenue under the Nippon Shinyaku Collaboration Agreement during the year ended December 31, 2025. For additional information regarding the Nippon Shinyaku Collaboration Agreement, please refer to Note 10, “License and Collaboration Agreements—Nippon Shinyaku Collaboration and License Agreement” to the accompanying audited consolidated financial statements. In May 2025, we entered into a loan agreement with entities managed by Healthcare Royalty Management, LLC (collectively and with other affiliated entities, HCR). Pursuant to the terms of the loan agreement, future royalties, sales-based milestone payments and certain development milestone payments earned under the Nippon Shinyaku Collaboration Agreement, along with consideration earned under various other NAV Technology Platform license agreements, shall be used to repay principal and interest owed to HCR. For additional information regarding the May 2025 loan agreement with HCR, please refer to Note 7, “Royalty Monetization Liabilities—2025 Royalty Bond” to the accompanying audited consolidated financial statements. NAV Technology Licensing Platform In addition to our internal product development efforts, we also selectively license the NAV Technology Platform and other intellectual property rights to other leading biotechnology and pharmaceutical companies, which we refer to as NAV Technology Licensees. As of December 31, 2025, our NAV Technology Platform was being applied in two commercial products, Zolgensma ® and Itvisma ® , and the preclinical and clinical development of various other licensed products. Licensing the NAV Technology Platform allows us to maintain our internal product development focus on our core disease indications and therapeutic areas while still expanding the NAV gene therapy pipeline, developing a greater breadth of treatments for patients, providing additional technological and potential clinical proof-of-concept for our NAV Technology Platform and creating additional revenue opportunities. Financial Overview Revenues Our revenues to date have been primarily generated from the licensing of our NAV Technology Platform and other intellectual property rights to NAV Technology Licensees and collaborators. We have not generated any revenues from commercial sales of our own products. If we fail to complete the development of our product candidates in a timely manner or obtain regulatory approval and adequate labeling, our ability to generate future revenues will be materially compromised. 75 Table of Contents We license our NAV Technology Platform and other intellectual property rights to other biotechnology and pharmaceutical companies, including collaborators for the joint development and commercialization of our product candidates. The terms of the licenses vary, and licenses may be exclusive or non-exclusive and may be sublicensable by the licensee. Licenses may grant intellectual property rights for purposes of internal and preclinical research and development only, or may include the rights, or options to obtain future rights, to commercialize drug therapies for specific diseases using the NAV Technology Platform and other licensed rights. License agreements generally have a term at least equal to the life of the underlying patents, but are terminable at the option of the licensee. Consideration payable to us under our license and collaboration agreements may include: (i) up-front and annual fees, (ii) milestone payments based on the achievement of certain development and sales-based milestones, (iii) sublicense fees, (iv) royalties on sales of licensed products, (v) fees for services related to the development and manufacturing of licensed products and (vi) other consideration payable upon optional goods and services purchased by licensees and collaborators. Future revenues under our license and collaboration arrangements are dependent on the successful development and commercialization of licensed products, which is uncertain, and revenues may fluctuate significantly from period to period. Additionally, we may never receive consideration under our license or collaboration agreements that is contemplated on optional goods and services, development and sales-based milestones, royalties on sales of licensed products or sublicense fees, given the contingent nature of these payments. Our revenues are concentrated among a low number of licensees and collaborators and the arrangements are terminable at the option of the counterparty. The termination of our license and collaborations arrangements may materially impact the amount of revenue we recognize in future periods. Please refer to Note 16, “Segment and Geographical Information” to the accompanying audited consolidated financial statements for a description of segment and geographical information regarding our revenues. Zolgensma and Itvisma Royalties Royalty revenue to date consists primarily of royalties on net sales of Zolgensma and Itvisma, which are marketed by Novartis Gene Therapies, Inc. (Novartis Gene Therapies), a wholly owned subsidiary of Novartis AG (Novartis), for the treatment of spinal muscular atrophy (SMA). Zolgensma and Itvisma are licensed products under our license agreement with Novartis Gene Therapies for the development and commercialization of treatments for SMA using the NAV Technology Platform. Operating Expenses Our operating expenses consist primarily of cost of license and royalty revenues, research and development expenses and general and administrative expenses. Personnel costs including salaries, wages, benefits, bonuses and stock-based compensation expense, comprise a significant component of research and development and general and administrative expenses. We allocate indirect expenses associated with our facilities, information technology costs, depreciation and other overhead costs between research and development and general and administrative categories based on employee headcount and the nature of work performed by each employee or using other reasonable allocation methodologies. Cost of License and Royalty Revenues Our cost of license and royalty revenues consists primarily of upstream fees due to our licensors as a result of revenue generated from the licensing of our NAV Technology Platform and other intellectual property rights, including sublicense fees and royalties on net sales of licensed products. Sublicense fees are based on a percentage of license fees received by us from licensees and are recognized in the period that the underlying license revenue is recognized. Royalties are based on a percentage of net sales of licensed products by licensees and are recognized in the period that the underlying sales occur. Future costs of revenues are uncertain due to the nature of our license agreements and significant fluctuations in cost of license and royalty revenues may occur from period to period. Research and Development Expense Our research and development expenses consist primarily of: • salaries, wages and personnel-related costs, including benefits, travel and stock-based compensation, for our scientific personnel and others performing research and development activities; • costs related to executing preclinical studies and clinical trials; • costs related to acquiring, developing and manufacturing materials for preclinical studies and clinical trials; 76 Table of Contents • fees paid to consultants and other third parties who support our product candidate development; • other costs in seeking regulatory approval of our product candidates; and • direct costs and allocated costs related to laboratories and facilities, depreciation expense, information technology and other overhead. Up-front fees incurred in obtaining technology licenses for research and development activities, as well as associated milestone payments, are charged to research and development expense as incurred if the technology licensed has no alternative future use. We expect to continue to incur significant research and development expenses for the foreseeable future as we continue the development of our product candidates and engage in early research and development for prospective product candidates and new technologies. The following table summarizes our research and development expenses incurred during the years ended December 31, 2025 and 2024 (in thousands): Years Ended December 31, 2025 2024 Direct Expenses ABBV-RGX-314 $ 37,599 $ 36,401 RGX-202 26,338 14,419 RGX-121 12,817 12,143 Other product candidates 6,771 7,103 Total direct expenses 83,525 70,066 Unallocated Expenses Platform and early research 29,362 27,885 Personnel 73,508 65,950 Facilities 11,276 11,410 Stock-based compensation 15,977 17,985 Depreciation and amortization 14,651 15,226 Total unallocated expenses 144,774 138,456 Total research and development $ 228,299 $ 208,522 Direct expenses related to the development of ABBV-RGX-314 for the years ended December 31, 2025 and 2024 include net cost reimbursement from AbbVie under our eye care collaboration of $60.2 million and $78.3 million, respectively, which were recorded as a reduction of research and development expenses. In addition to reimbursement of direct development expenses, net cost reimbursement from AbbVie includes reimbursement of personnel and overhead costs attributable to the development of ABBV-RGX-314, the underlying costs of which are reported as unallocated expenses in the table above. We typically utilize our employee and infrastructure resources across our development programs. As a result, we generally do not allocate personnel and other internal costs, such as facilities and other overhead costs, to specific product candidates or development programs. Platform and early research reported in the table above includes direct costs not identifiable with a specific lead product candidate, including costs associated with our research and development platform used across programs, manufacturing support, process and analytical development, early research and development for prospective product candidates and new technologies, and other costs in support of research and development activities. General and Administrative Expense Our general and administrative expenses consist primarily of salaries, wages and personnel-related costs, including benefits, travel and stock-based compensation, for employees performing functions other than research and development. This includes certain personnel in executive, commercial, corporate development, finance, legal, human resources, information technology, facilities and administrative support functions. Additionally, general and administrative expenses include costs associated with accounting, legal, commercial and other corporate advisory services, obtaining and maintaining patents, insurance, information systems and other general corporate activities, as well as facility-related costs and other corporate overhead costs not otherwise allocated to research and development expense. We expect that our general and administrative expenses will increase as we continue to develop, and potentially commercialize, our product candidates. Specifically, we expect general and administrative costs associated with the potential commercialization of our product candidates to increase in future periods as we and our commercial partners prepare for and carry out product launch efforts, in particular for the potential commercialization of our RGX-202 and ABBV-RGX-314 product candidates. 77 Table of Contents Other Income (Expense) Interest Income from Licensing In accordance with our revenue recognition policy, interest income from licensing consists of imputed interest recognized from significant financing components identified in our license agreements with NAV Technology Licensees. Investment Income Investment income consists of interest income earned and gains and losses realized from our cash equivalents, marketable securities and non-marketable equity securities. Cash equivalents are comprised of money market mutual funds and highly liquid debt securities with original maturities of 90 days or less at acquisition. Marketable securities are comprised of available-for-sale debt securities. Interest Expense Interest expense is primarily associated with our royalty monetization liabilities, including our December 2020 royalty purchase agreement (2020 Royalty Purchase Agreement) and May 2025 loan agreement (2025 Royalty Bond) with HCR. For further information regarding our royalty monetization liabilities and associated interest expense, please refer to Note 7, “Royalty Monetization Liabilities” to the accompanying audited consolidated financial statements. Critical Accounting Policies and Estimates This Management’s Discussion and Analysis of Financial Condition and Results of Operations is based on our consolidated financial statements, which we have prepared in accordance with accounting principles generally accepted in the United States of America (GAAP). The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and related disclosure of contingent assets and liabilities for the periods presented. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities, and other reported amounts, that are not readily apparent from other sources. Actual results may differ materially from these estimates under different assumptions or conditions. Our significant accounting policies are fully described in Note 2, “Summary of Significant Accounting Policies” to our audited consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K. We believe the following accounting policies are critical to the process of making significant judgments and estimates in the preparation of our financial statements and understanding and evaluating our reported financial results. Revenue Recognition We recognize revenue in accordance with Accounting Standards Codification (ASC) 606, Revenue from Contracts with Customers (ASC 606). ASC 606 requires entities to recognize revenue when control of the promised goods or services is transferred to customers at an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The following five steps are performed to determine the appropriate revenue recognition for arrangements within the scope of ASC 606: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract and (v) recognize revenue when (or as) the entity satisfies the performance obligations. We apply the five-step model to contracts that are within the scope of ASC 606 only when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. At contract inception, for contracts within the scope of ASC 606, we assess the goods or services promised within each contract and determine those that are performance obligations and whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price that is allocated to respective performance obligations when (or as) the respective performance obligations are satisfied. We evaluate our contracts with customers for the presence of significant financing components. If a significant financing component is identified in a contract and provides a financing benefit to the customer, the transaction price for the contract is adjusted to account for the financing portion of the arrangement, which is recognized as interest income over the financing term using the effective interest method. In determining the appropriate interest rates for significant financing components, we evaluate the credit profile of the customer and prevailing market interest rates and select an interest rate in which we believe would be charged to the customer in a separate financing arrangement over a similar financing term. 78 Table of Contents We license our NAV Technology Platform and other intellectual property rights to other biotechnology and pharmaceutical companies, including collaborators for the joint development and commercialization of our product candidates. The terms of the licenses vary, and licenses may be exclusive or non-exclusive and may be sublicensable by the licensee. Licenses may grant intellectual property rights for purposes of internal and preclinical research and development only, or may include the rights, or options to obtain future rights, to commercialize drug therapies for specific diseases using the NAV Technology Platform and other licensed rights. License agreements generally have a term at least equal to the life of the underlying patents, but are terminable at the option of the licensee. Consideration payable to us under our license and collaboration agreements may include: (i) up-front and annual fees, (ii) milestone payments based on the achievement of certain development and sales-based milestones, (iii) sublicense fees, (iv) royalties on sales of licensed products, (v) fees for services related to the development and manufacturing of licensed products and (vi) other consideration payable upon optional goods and services purchased by licensees and collaborators. We evaluate our agreements with collaboration partners to determine whether they are within the scope of ASC 808, Collaborative Arrangements (ASC 808). For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we identify the various transactions with the counterparty and determine if any unit of account is more reflective of a transaction with a customer and therefore should be accounted for within the scope of ASC 606. For transactions that are accounted for pursuant to ASC 606, we apply the five-step model as described in our revenue recognition policies. For transactions that are accounted for pursuant to ASC 808, an appropriate method of recognition and presentation is determined and consistently applied in accordance with our accounting policies for collaborative arrangements. Our license and collaboration agreements are accounted for as contracts with customers within the scope of ASC 606, with the exception of transactions for which the counterparty is determined not to be a customer. At the inception of each agreement, we determine the contract term for purposes of applying the requirements of ASC 606. Licenses are generally terminable at the option of the licensee with advance notice to us. For each license granted, we evaluate these termination rights to determine whether a substantive termination penalty would be incurred by the licensee upon termination. If the licensee incurs a substantive termination penalty upon termination, the contract term for revenue recognition purposes is generally equal to the stated term of the license, which is the life of the underlying licensed patents. Alternatively, if the licensee does not incur a substantive termination penalty upon termination, the contract term for revenue recognition purposes may be shorter than the stated term of the license, in which case the termination rights may be accounted for as contract renewal options. Performance obligations under our license and collaboration agreements may include (i) the delivery of intellectual property licenses, (ii) development and manufacturing services to be performed by us related to licensed products and (iii) options granted to purchase additional goods and services, to the extent the options convey material rights. At the inception of each license agreement which contains performance obligations for development, manufacturing or other services, we evaluate whether the license is distinct from the services, which requires judgment. In making this determination, we consider, among other things, the stage of development of the licensed products and whether the services will significantly impact further development of the licensed products. If it is determined that the license is not distinct from the services, the license is combined with the services into a single performance obligation. Agreements may provide licensees and collaborators with options to purchase additional goods or other services, including options to purchase commercial supply of licensed products. Options are evaluated at the inception of the agreement to determine whether they provide material rights to the customer. In making this determination, we consider whether the options are priced at an incremental discount to the standalone selling price of the underlying goods or services, in which case the option is considered to be a material right. Material rights are accounted for as separate performance obligations under the current arrangement. We evaluate the transaction price of our license and collaboration agreements at contract inception and at each reporting date. The transaction price includes the fixed consideration payable to us over the contract term, as well as any variable consideration to the extent that it is probable that a significant reversal of revenue will not occur in the future. Fixed consideration under the agreements may include up-front and annual fees payable to us over the contract term and fixed fees for development, manufacturing and other services. Variable consideration under the agreements may include development and sales-based milestone payments, payments for development, manufacturing and other services, sublicense fees and royalties on sales of licensed products. Consideration contingent upon the exercise of options by the customer is excluded from the transaction price and not accounted for as part of the arrangement until the option is exercised. The transaction price of our license and collaboration arrangements is allocated to the underlying performance obligations based on their relative standalone selling prices and recognized as revenue when (or as) the performance obligations are satisfied. Variable consideration payable based on services performed is allocated directly to the performance obligation for such services. Consideration allocated to performance obligations for the delivery of intellectual property licenses is recognized as license and royalty revenue in full upon the delivery of the license. Consideration allocated to performance obligations for development, manufacturing and other services is recognized as service revenue as we perform the services. Consideration allocated to performance obligations for material rights to purchase additional goods and services is recognized as revenue upon the satisfaction of the performance obligations underlying the optional goods and services purchased by the customer. Service revenue is recognized using a measure of progress that 79 Table of Contents best reflects the pattern of satisfaction of the performance obligations. At each reporting date, we re-evaluate the measure of progress and adjust service revenue on a cumulative catch-up basis to reflect our best estimate of the services performed to date versus the total services to be performed under the arrangement. Development milestone payments are payable to us upon the achievement of specified development milestones. At the inception of each license agreement that contains development milestone payments, we evaluate whether the milestones are probable of achievement and estimate the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal will not occur in the future, milestone payments are included in the transaction price. Milestone payments contingent on the achievement of development milestones that are not within our control or the control of the licensee, such as regulatory approvals, are not considered probable of being achieved and are excluded from the transaction price until the milestone is achieved. At each reporting date, we re-evaluate the probability of achievement of each outstanding development milestone and, if necessary, adjust the transaction price for any milestones for which the probability of achievement has changed due to current facts and circumstances. The increase to the transaction price as a result of any such adjustments is then allocated to the underlying performance obligations in a manner similar to the allocation of the initial transaction price and, to the extent the performance obligations are satisfied, recognized as revenue on a cumulative catch-up basis in the period of the adjustment. Royalties on sales of licensed products, sales-based milestone payments, including milestones payable upon first commercial sales of licensed products, and sublicense fees based on the receipt of certain fees by licensees from any sublicensees are excluded from the transaction price of each license and recognized as license and royalty revenue in the period that the related sales or sublicenses occur, provided that the associated license has been delivered to the licensee. Royalty revenue to date consists primarily of royalties on net sales of Zolgensma and Itvisma, which are licensed products under our license agreement with Novartis Gene Therapies for the development and commercialization of treatments for SMA. We recognize royalty revenue from net sales of Zolgensma and Itvisma in the period in which the underlying products are sold by Novartis Gene Therapies, which in certain cases may require us to estimate royalty revenue for periods of net sales which have not yet been reported to us. Estimated royalties are reconciled to actual amounts reported in subsequent periods, and any differences are recognized as an adjustment to royalty revenue in the period the royalties are reported. We receive payments from licensees and collaborators based on the billing schedules established in the associated agreements. Amounts recognized as revenue which have not yet been received from the customer are recorded as accounts receivable when our rights to the consideration are conditional solely upon the passage of time. Amounts recognized as revenue which have not yet been received from customers are recorded as contract assets when our rights to the consideration are not unconditional. Contract assets are recorded as other current assets on the consolidated balance sheets if the consideration is expected to be realized within 12 months from the reporting date, or as other assets if the consideration is expected to be realized in periods beyond 12 months from the reporting date. If a licensee elects to terminate a license prior to the end of the license term, the licensed intellectual property is returned to us and any consideration recorded as accounts receivable or contract assets which is not contractually payable by the licensee is charged off as a reduction of revenue in the period of the termination. Amounts received by us prior to the delivery of underlying performance obligations are deferred and recognized as revenue upon the satisfaction of the performance obligations. Deferred revenue which is not expected to be recognized within 12 months from the reporting date is recorded as non-current on the consolidated balance sheets. Collaborative Arrangements We evaluate our agreements with collaboration partners to determine whether they are within the scope of ASC 808. Such arrangements are within the scope of ASC 808 if they involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. This evaluation is performed throughout the life of the arrangement based on any changes in the roles and responsibilities of the parties under the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we identify the various transactions with the counterparty and determine if any unit of account is more reflective of a transaction with a customer and therefore should be accounted for within the scope of ASC 606. For transactions that are accounted for pursuant to ASC 606, we apply the five-step model as described in our revenue recognition policies. For transactions that are accounted for pursuant to ASC 808, an appropriate method of recognition and presentation is determined and consistently applied. For additional information regarding our collaborative arrangements, including our collaborations with AbbVie and Nippon Shinyaku, refer to Note 10, “License and Collaboration Agreements” to the accompanying audited consolidated financial statements. 80 Table of Contents Accrued Research and Development Expenses We estimate our accrued research and development expenses as of each balance sheet date. This process involves reviewing contracts and purchase orders with service providers, identifying services that have been performed on our behalf and estimating the level of service performed, the expected remaining period of performance and the associated expenses incurred for the service when we have not yet been invoiced or otherwise notified of actual cost. Depending on the timing of payments to the service providers and the estimated expenses incurred, we may record net prepaid or accrued research and development expenses relating to these costs. Examples of estimated accrued research and development expenses include fees paid to: • Contract research organizations (CROs) and other vendors in connection with preclinical development and clinical studies; • Contract manufacturing organizations (CMOs) and other vendors related to process development and manufacturing of materials for use in preclinical development and clinical studies; and • service providers for professional service fees such as consulting and other research and development related services. Our understanding of the status and timing of services performed relative to the actual status and timing may vary and may result in us reporting changes in estimates in any particular period. To date, there have been no material differences from our estimates to the amount actually incurred. Stock-based Compensation We account for our stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation (ASC 718). ASC 718 requires all stock-based awards to employees and nonemployees to be recognized as expense based on the grant date fair value of the awards. Our stock-based awards include stock options and restricted stock units granted to employees and nonemployees and shares issued to employees under our employee stock purchase plan. Our stock-based awards may be subject to either service or performance-based vesting conditions. Compensation expense related to awards with service-based vesting conditions is recognized on a straight-line basis based on the estimated grant date fair value over the requisite service period of the award, which is generally the vesting term. Compensation expense related to awards with performance-based vesting conditions is recognized based on the estimated grant date fair value over the requisite service period using the accelerated attribution method to the extent achievement of the performance condition is probable. We have elected to not estimate forfeitures of stock-based awards and account for forfeitures as they occur. We estimate the fair value of our stock option awards using the Black-Scholes option-pricing model, which requires the input of subjective assumptions, including (i) the fair value of the underlying common stock, (ii) the expected stock price volatility, (iii) the expected term of the award, (iv) the risk-free interest rate and (v) expected dividends. The fair value of our common stock, as used as an input to determine the fair value of our stock option awards, is based on the closing price of our common stock on the date of the grant. We estimate expected stock price volatility based on the historical volatility of our common stock over a period of time commensurate with the expected term of our stock option awards. Due to the lack of sufficient historical data, we estimate the expected term of our employee stock options using the “simplified” method, whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. For stock options granted to nonemployees, we use the contractual term of the award rather than expected term to estimate the fair value of the award. We estimate the risk-free interest rates for periods within the expected term of its options based on the rates of U.S. Treasury securities with maturity dates commensurate with the expected term of the associated awards. We assume a dividend yield of zero for our common stock as we have never paid dividends and do not expect to pay dividends for the foreseeable future. We estimate the fair value of our restricted stock units based on the closing price of our common stock on the date of the grant. Royalty Monetization Liabilities Net proceeds received under our royalty monetization agreements with HCR are recorded as liabilities and accounted for as debt. The liabilities are amortized over the estimated life of the arrangements using the effective interest method. For arrangements in which there is no stated interest rate, the total amount of royalty and other payments paid to HCR under the arrangement, less the net proceeds we received from HCR, is recorded as interest expense over the life of the arrangement. We estimate the effective interest rates of our royalty monetization liabilities based on our estimate of total payments to be paid to HCR under the arrangement. We reassess these estimates at each reporting date and adjust the effective interest rate and amortization of the liabilities on a prospective basis as necessary. 81 Table of Contents Income Taxes We account for income taxes in accordance with ASC 740, Income Taxes, which provides for deferred taxes using an asset and liability approach. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are provided if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. As of December 31, 2025, we had federal net operating loss (NOL) carryforwards of $754.4 million, U.S. state NOL carryforwards of $394.9 million and federal and state research and development tax credit carryforwards of $95.1 million which may be available to offset future income tax liabilities. Our federal NOL carryforwards and a portion of our state NOL carryforwards as of December 31, 2025 may be carried forward indefinitely. The remaining portion of our state NOL carryforwards and our federal and state credit carryforwards as of December 31, 2025 expire at various dates between 2029 and 2045. We have evaluated the positive and negative evidence bearing upon the realizability of our deferred tax assets, including our NOL and credit carryforwards. Based on our history of operating losses, and other relevant facts and circumstances, we concluded that it is more likely than not that the benefit of our deferred tax assets will not be realized. Accordingly, we provided a full valuation allowance for our net deferred tax assets as of December 31, 2025 and 2024. Results of Operations Our consolidated results of operations were as follows (in thousands): Years Ended December 31, 2025 2024 Change Revenues License and royalty revenue $ 156,267 $ 81,960 $ 74,307 Service revenue 14,174 1,368 12,806 Total revenues 170,441 83,328 87,113 Operating Expenses Cost of license and royalty revenues 20,298 33,567 (13,269 ) Research and development 228,299 208,522 19,777 General and administrative 82,863 76,619 6,244 Credit losses (recoveries) — (5,000 ) 5,000 Impairment of long-lived assets — 2,101 (2,101 ) Other operating expenses 179 865 (686 ) Total operating expenses 331,639 316,674 14,965 Loss from operations (161,198 ) (233,346 ) 72,148 Other Income (Expense) Interest income from licensing 83 174 (91 ) Investment income 12,245 18,729 (6,484 ) Interest expense (45,008 ) (12,659 ) (32,349 ) Total other income (expense) (32,680 ) 6,244 (38,924 ) Net loss $ (193,878 ) $ (227,102 ) $ 33,224 Comparison of the Years Ended December 31, 2025 and 2024 License and Royalty Revenue. License and royalty revenue increased by $74.3 million, from $82.0 million for the year ended December 31, 2024 to $156.3 million for the year ended December 31, 2025. The increase was primarily attributable to $72.9 million of up-front license revenue recognized under our collaboration with Nippon Shinyaku in 2025, as well as an increase in royalty revenues for Zolgensma and Itvisma. Total royalty revenues for Zolgensma and Itvisma increased by $1.7 million, from $81.5 million in 2024 to $83.2 million in 2025. Novartis reported combined Zolgensma and Itvisma sales of $1.23 billion in 2025, as compared to $1.21 billion in 2024. As reported by Novartis, the increase reflects continued strong demand for Zolgensma in the incident SMA population, and was partially driven by the approval and launch of Itvisma in the fourth quarter of 2025. Zolgensma and Itvisma royalty revenues for 2025 were $82.5 million and $0.6 million, respectively. Itvisma royalties for 2025 reflect a product launch in the late fourth quarter of 2025. 82 Table of Contents Service Revenue. Service revenue increased by $12.8 million, from $1.4 million for the year ended December 31, 2024 to $14.2 million for the year ended December 31, 2025. The increase was primarily attributable to $11.8 million of service revenue recognized under our collaboration with Nippon Shinyaku in 2025, largely driven by the performance of RGX-121 development and manufacturing services. Cost of License and Royalty Revenues. Cost of license and royalty revenues decreased by $13.3 million, from $33.6 million for the year ended December 31, 2024 to $20.3 million for the year ended December 31, 2025. The decrease was largely driven by a reduction in upstream Zolgensma royalties payable to licensors for net sales in certain territories outside the United States. Research and Development Expense. Research and development expenses increased by $19.8 million, from $208.5 million for the year ended December 31, 2024 to $228.3 million for the year ended December 31, 2025. The increase was primarily attributable to the following: • an increase of $8.1 million in manufacturing-related expenses and other clinical supply costs for our lead product candidates, largely driven by manufacturing costs for ABBV-RGX-314, RGX-202 and RGX-121; • an increase of $5.8 million in personnel-related costs due to increased headcount of development personnel, net of a $2.0 million decrease in stock-based compensation expense; and • an increase of $5.7 million in costs associated with clinical trials and regulatory activities, largely driven by clinical trial expenses for RGX-202 pivotal trials. General and Administrative Expense. General and administrative expenses increased by $6.2 million, from $76.6 million for the year ended December 31, 2024 to $82.9 million for the year ended December 31, 2025. The increase was largely driven by professional services, consulting and other corporate advisory services. Credit Losses (Recoveries). We recognized credit recoveries of $5.0 million during the year ended December 31, 2024 upon the full collection of amounts due under our settlement agreement with Abeona Therapeutics Inc. (Abeona), for which we had previously recorded an allowance for credit losses. For further information regarding the settlement agreement with Abeona and the allowance for credit losses, please refer to Note 10, “License and Collaboration Agreements—Settlement Agreement with Abeona Therapeutics” to the accompanying audited consolidated financial statements. We did not record any credit losses or recoveries during the year ended December 31, 2025. Investment Income. Investment income decreased by $6.5 million, from $18.7 million for the year ended December 31, 2024 to $12.2 million for the year ended December 31, 2025. The decrease was primarily attributable to the achievement of milestones associated with the July 2021 acquisition of our non-marketable equity securities of Corlieve Therapeutics SAS (Corlieve) by uniQure N.V. (uniQure). We recognized realized gains of $6.6 million upon the achievement of such milestones during 2024. No such milestones were achieved during 2025 and no gains were realized during the period. Interest Expense. Interest expense increased by $32.3 million, from $12.7 million for the year ended December 31, 2024 to $45.0 million for the year ended December 31, 2025. The increase was primarily attributable to interest expense under our royalty monetization liabilities, driven largely by an increase in forecasted Zolgensma and Itvisma royalties expected to be paid to HCR under the 2020 Royalty Purchase Agreement and interest expense incurred to date under the 2025 Royalty Bond issued in May 2025. Liquidity and Capital Resources Sources of Liquidity As of December 31, 2025, we had cash, cash equivalents and marketable securities of $240.9 million, which were primarily derived from the royalty monetization in May 2025, the up-front payment received under the Nippon Shinyaku Collaboration Agreement in March 2025 and the sale of our common stock and pre-funded warrants in March 2024, each as described below: • In May 2025, we entered into a loan agreement with HCR pursuant to which HCR will provide us with an aggregate limited recourse loan of up to $250.0 million (the 2025 Royalty Bond). The 2025 Royalty Bond is disbursable to us in three tranches, with $150.0 million funded on the closing date in May 2025, $50.0 million available to be funded if sales of a specified product exceed a specified sales threshold prior to December 31, 2026, and $50.0 million available to be funded if both parties exercise an option in 2027. Proceeds received from the initial funding tranche of the 2025 Royalty Bond in May 2025, net of discounts and transaction costs, were $144.5 million. The 2025 Royalty Bond matures in 2035, subject to potential extension, and bears interest at a rate of 9.75% plus the 3-month secured overnight financing rate as administered by the Federal Reserve Bank of New York (SOFR), with a minimum interest rate of 14.0%. Prior to the maturity date, interest and principal under the 2025 Royalty Bond will be paid quarterly to HCR solely using proceeds 83 Table of Contents received, net of upstream obligations to licensors, from certain specified royalties, milestone payments, license fees and other consideration payable to us under the Zolgensma and Itvisma license with Novartis Gene Therapies, the Nippon Shinyaku Collaboration Agreement and certain other NAV Technology Platform license agreements. • In January 2025, we entered into the Nippon Shinyaku Collaboration Agreement for the development and commercialization of RGX-121 and RGX-111 in the United States and certain countries in Asia. Pursuant the Nippon Shinyaku Collaboration Agreement, we received an up-front payment of $110.0 million following the effective date of the agreement in March 2025 and are eligible to receive up to $700.0 million upon the achievement of specified development and sales-based milestones. We are also eligible to receive double-digit royalties on net sales of RGX-121 and RGX-111 by Nippon Shinyaku, subject to specified offsets and reductions. • In March 2024, we completed a public offering of 4,565,260 shares of our common stock at a price of $23.00 per share and 1,521,740 pre-funded warrants to purchase shares of our common stock at a price of $22.9999 per pre-funded warrant, which equaled the public offering price per share of the common stock less the $0.0001 exercise price of each pre-funded warrant. The aggregate net proceeds received from the offering were $131.1 million, net of underwriting discounts and commissions and offering expenses. At-the-Market Offering Program In December 2024, we entered into a Sales Agreement with Leerink Partners LLC (Leerink) pursuant to which we may offer and sell shares of our common stock having an aggregate offering price of up to $150.0 million from time to time through Leerink, acting as our sales agent (the Leerink ATM Program). As of December 31, 2025, no shares of common stock had been sold under the Leerink ATM Program. We intend to use proceeds obtained from the sale of shares under the Leerink ATM Program, if any, for general corporate purposes. Future Liquidity and Ability to Continue as a Going Concern We intend to devote the majority of our current capital to preclinical research, clinical development, seeking regulatory approval of our product candidates and, if approved, commercialization of our product candidates, as well as additional capital expenditures needed to support these activities. Because of the numerous risks and uncertainties associated with the development and commercialization of gene therapy product candidates, we are unable to estimate the total amount of operating expenditures and capital outlays necessary to complete the development and commercialization of our product candidates. We expect that our cash, cash equivalents and marketable securities of $240.9 million as of December 31, 2025 will enable us to fund our operating expenses and capital expenditure requirements, and are sufficient to meet our financial commitments and obligations into early 2027. This estimate is based on our current operating plan, and excludes the potential effects of any future financings or material milestone payments that may be received under our licensing and collaboration arrangements. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our capital resources sooner than expected. These conditions raise substantial doubt about our ability to continue as a going concern within 12 months from the issuance date of our consolidated financial statements for the year ended December 31, 2025, which accompany this Annual Report on Form 10-K. Our ability to continue as a going concern will depend heavily on the successful development, approval and commercialization of our product candidates and our ability to raise additional capital to fund operations. If we are unable to raise capital sufficient to meet our working capital needs in the future, we may be forced to delay expenditures, reduce the scope of our development activities or make other changes to our operating plans. Cash Flows Our consolidated cash flows were as follows (in thousands): Years Ended December 31, 2025 2024 Net cash used in operating activities $ (123,963 ) $ (173,125 ) Net cash provided by (used in) investing activities (15,868 ) 103,446 Net cash provided by financing activities 116,771 92,683 Net increase (decrease) in cash and cash equivalents and restricted cash $ (23,060 ) $ 23,004 84 Table of Contents Cash Flows from Operating Activities Our net cash used in operating activities for the year ended December 31, 2025 decreased by $49.2 million from the year ended December 31, 2024, largely as a result of the $110.0 million up-front fee received from Nippon Shinyaku in March 2025, partially offset by an increase in operating expenses in 2025. We expect to continue to incur regular net cash outflows from operations for the foreseeable future as we continue the development and advancement of our product candidates and other research programs. For the year ended December 31, 2025, our net cash used in operating activities of $124.0 million consisted of a net loss of $193.9 million, offset by adjustments for non-cash items of $58.1 million and favorable changes in operating assets and liabilities of $11.8 million. Adjustments for non-cash items primarily consisted of stock-based compensation expense of $34.6 million, depreciation and amortization expense of $15.6 million, and non-cash interest expense of $12.9 million. The changes in operating assets and liabilities include an increase in deferred revenue of $29.3 million, which was primarily attributable to the deferred portion of the $110.0 million up-front payment received under our collaboration with Nippon Shinyaku in the first quarter of 2025. The favorable changes in operating assets and liabilities were partially offset by an increase in accounts receivable of $7.7 million, which was driven largely by reimbursable costs due from Nippon Shinyaku under our collaboration for RGX-121 and RGX-111 and royalties receivable on net sales of Zolgensma and Itvisma. Other changes in operating working capital occurred in the normal course of business. For the year ended December 31, 2024, our net cash used in operating activities of $173.1 million consisted of a net loss of $227.1 million, offset by adjustments for non-cash items of $48.4 million and favorable changes in operating assets and liabilities of $5.5 million. Adjustments for non-cash items primarily consisted of stock-based compensation expense of $38.5 million and depreciation and amortization expense of $16.2 million, partially offset by realized gains on investments, credit recoveries and the accretion of discounts on marketable debt securities during the period. The changes in operating assets and liabilities include a decrease in total accounts receivable of $9.7 million, which was driven largely by a decrease in Zolgensma royalties receivable and the full collection of amounts due under our settlement agreement with Abeona, for which we recorded a $5.0 million credit recovery during the period. The changes in operating assets and liabilities also include a total decrease in prepaid expenses and other current assets of $12.0 million, which was driven primarily by decreases in prepaid fees to CROs and net cost reimbursement due from AbbVie under our ABBV-RGX-314 collaboration. The favorable changes in operating assets and liabilities were partially offset by a decrease in accrued expenses and other current liabilities of $12.1 million, which was driven primarily by decreases in accruals for external research and development services and sublicense and royalties due to licensors. Other changes in operating working capital occurred in the normal course of business. Cash Flows from Investing Activities For the year ended December 31, 2025, our net cash used in investing activities primarily consisted of $332.6 million used to purchase marketable debt securities and $2.4 million used to purchase property and equipment, partially offset by $319.1 million in maturities of marketable debt securities. For the year ended December 31, 2024, our net cash provided by investing activities consisted of $290.2 million in maturities of marketable debt securities and $5.8 million in proceeds received from uniQure upon the achievement of milestones associated with their acquisition of Corlieve, offset by $190.1 million used to purchase marketable debt securities and $2.4 million used to purchase property and equipment. Cash Flows from Financing Activities For the year ended December 31, 2025, our net cash provided by financing activities primarily consisted of $144.5 million in proceeds received from the issuance of the 2025 Royalty Bond and warrants to HCR in May 2025, net of discounts and transaction costs paid during the period, and was partially offset by $28.1 million of royalties paid, net of interest, under our royalty monetization liabilities. For the year ended December 31, 2024, our net cash provided by financing activities primarily consisted of $131.1 million in proceeds received from the public offering of common stock and pre-funded warrants completed in March 2024, net of underwriting discounts and commissions and other offering expenses paid during the period, and $2.7 million in proceeds received from the exercise of stock options and issuance of common stock under our employee stock purchase plan. Our net cash provided by financing activities was partially offset by $39.9 million of royalties paid, net of interest, under our royalty monetization liabilities. 85 Table of Contents Additional Capital Requirements Our material capital requirements from known contractual and other obligations primarily relate to our vendor service contracts and purchase commitments, in-license agreements, operating lease agreements and royalty monetization agreements. In the normal course of business, we enter into services agreements with CROs, CMOs and other third parties. Generally, these agreements provide for termination upon notice, with specified amounts due upon termination based on the timing of termination and the terms of the agreement. The amounts and timing of payments under these agreements are uncertain and contingent upon the initiation and completion of the services to be provided. Obligations to licensors under our in-license agreements may include sublicense fees, milestones fees, royalties and reimbursement of patent maintenance costs. Sublicense fees are payable to licensors when we sublicense underlying intellectual property to third parties; the fees are based on a percentage of the license fees we receive from sublicensees. Milestone fees are payable to licensors upon our future achievement of certain development, regulatory and commercial milestones. Royalties are payable to licensors based on a percentage of net sales of licensed products. Patent maintenance costs are payable to licensors as reimbursement for the cost of maintaining licensed patents. Due to the contingent nature of the payments, the amounts and timing of payments to licensors under our in-license agreements are uncertain and may fluctuate significantly from period to period. In March 2022, we entered into a letter agreement (the Penn Letter Agreement) with The Trustees of the University of Pennsylvania (Penn) to buy out our obligation to pay sublicense fees under our license agreement with Penn (the Penn License). Pursuant to the letter agreement, we are obligated to pay Penn a total of $12.0 million to satisfy any other past or future obligations to pay sublicense fees under the Penn License, which is payable in four equal annual installments of $3.0 million beginning in March 2023. We are no longer obligated to pay sublicense fees to Penn under the license agreement, but remain obligated to pay Penn royalties on net sales of licensed products, milestone fees and reimbursement of certain patent maintenance costs in accordance with the Penn License. As of December 31, 2025, we had $3.0 million remaining payable to Penn under the Penn Letter Agreement, in addition to other amounts payable under the Penn License. We have entered into a number of long-term operating leases for office, laboratory and manufacturing space in Rockville, Maryland, Washington, D.C. and New York, New York, as well as a number of laboratory and other equipment leases. As of December 31, 2025, we had recorded total lease liabilities of $73.5 million under our operating leases. Please refer to Note 6, “Leases” to the accompanying consolidated financial statements for further information regarding our lease commitments. Under the terms of the 2020 Royalty Purchase Agreement, our Zolgensma and Itvisma royalties, less amounts payable by us to certain licensors, are payable to HCR up to a specified capped amount. As of December 31, 2025, the total amount of future royalties payable to HCR under the 2020 Royalty Purchase Agreement was $35.5 million. We have no obligation to repay any amounts to HCR if total future Zolgensma and Itvisma royalty payments from Novartis are not sufficient to repay these amounts. Upon full repayment of our obligation under the 2020 Royalty Purchase Agreement, future Zolgensma and Itvisma royalties shall be included in the royalty interest payable to HCR under the 2025 Royalty Bond. Under the terms of the 2025 Royalty Bond, interest and principal shall be paid quarterly to HCR solely using proceeds received, net of upstream obligations to licensors, from certain specified royalties, milestone payments, license fees and other consideration payable to us under the Zolgensma and Itvisma license with Novartis Gene Therapies, the Nippon Shinyaku Collaboration Agreement and certain other NAV Technology Platform license agreements. If the proceeds received under the specified license agreements are insufficient to pay the quarterly interest due to HCR, unpaid interest will accrue to the principal balance. The 2025 Royalty Bond matures in May 2035, subject to potential extension, unless repaid in full at an earlier date. Upon maturity, the outstanding principal and interest shall be due and payable to HCR. Other than through the payment of proceeds received under the specified license agreements, the 2025 Royalty Bond may not be prepaid prior to maturity. The 2025 Royalty Bond is collateralized by a security interest and lien on the specified royalties and license fees. As of December 31, 2025, the principal balance outstanding under the 2025 Royalty Bond was $163.4 million. Future Funding Requirements We have incurred cumulative losses since our inception and had an accumulated deficit of $1.13 billion as of December 31, 2025. Our transition to recurring profitability is dependent upon achieving a level of revenues adequate to support our cost structure, which depends heavily on the successful development, approval and commercialization of our product candidates. We do not expect to achieve such revenues, and expect to continue to incur losses, for at least the next several years. We expect to continue to incur significant research and development and general and administrative expenses for the foreseeable future as we continue the development of, and seek regulatory approval for, our product candidates. Subject to obtaining regulatory approval for our product 86 Table of Contents candidates, we expect to incur significant commercialization expenses for product sales, marketing, manufacturing and distribution. Additionally, we expect to continue to incur capital expenditures associated with building out additional laboratory and manufacturing capacity to further support the development of our product candidates and potential commercialization efforts. As a result, we will need significant additional capital to fund our operations, which we may obtain through one or more equity offerings, debt financings or other third-party funding, including potential strategic alliances and licensing or collaboration arrangements. Our future capital requirements will depend on many factors, including: • the timing of enrollment, commencement and completion of our clinical trials; • the results of our clinical trials; • the results of our preclinical studies for our product candidates and any subsequent clinical trials; • the scope, progress, results and costs of drug discovery, laboratory testing, preclinical development and clinical trials for our product candidates; • delays or costs due to a clinical hold or CRL, including BLA resubmission; • whether we receive a PRV and are able to monetize or otherwise realize any potential value associated with such a voucher; • the value of any PRV received diminishes including any decreases due to demand for these vouchers; • the costs associated with building out additional laboratory and manufacturing capacity; • the costs, timing and outcome of regulatory review of our product candidates; • the impact of any government-imposed tariffs on cost of goods and services, particularly related to partnered product candidates; • the costs of future product sales, medical affairs, marketing, manufacturing and distribution activities for any of our product candidates for which we receive marketing approval; • revenue, if any, received from commercial sales of our products, should any of our product candidates receive marketing approval; • revenue received from commercial sales of Zolgensma and Itvisma, and the timing and amount of Zolgensma and Itvisma royalties paid to HCR under our royalty monetization agreements; • revenue received from other commercial sales of our licensees’ and collaborators’ products, should any of their product candidates receive marketing approval, other revenue received under our licensing agreements and collaborations, and the timing and amount of any such revenues payable to HCR under our royalty monetization agreements; • the costs of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights including against Sarepta and defending any intellectual property-related claims; • our current licensing agreements or collaborations remaining in effect, including the AbbVie Collaboration Agreement relating to ABBV-RGX-314 and the Nippon Shinyaku Collaboration Agreement relating to RGX-121 and RGX-111, and our ability to timely achieve any milestones set forth in such agreements or collaborations; • our ability to establish and maintain additional licensing agreements or collaborations on favorable terms, if at all; and • the extent to which we acquire or in-license other product candidates and technologies. The issuance of additional securities, whether equity or debt, by us, including through our at-the-market program, or the possibility of such issuance, may cause the market price of our common stock to decline. Adequate additional financing may not be available to us on acceptable terms, or at all. We also could be required to seek funds through arrangements with partners or otherwise that may require us to relinquish rights to our intellectual property, our product candidates or otherwise agree to terms unfavorable to us. Off-Balance Sheet Arrangements We did not have any off-balance sheet arrangements during the periods presented, and we do not currently have, any off-balance sheet arrangements, as defined in the rules and regulations of the SEC. 87 Table of Contents ITEM 7A. QUANTITATIVE AND QUALITAT IVE DISCLOSURES ABOUT MARKET RISK Interest Rate Risk We are exposed to market risk related to changes in interest rates. Our primary exposure to interest rate risk results from the cash equivalents and marketable securities in our investment portfolio. Our primary objectives in managing our investment portfolio are to preserve principal, maintain proper liquidity to meet operating needs and maximize yields. At any time, significant changes in interest rates can affect the fair value of the investment portfolio and its interest earnings. Currently, we do not hedge these interest rate exposures. As of December 31, 2025 and 2024, we had cash, cash equivalents and marketable securities of $240.9 million and $244.9 million, respectively. Our cash equivalents and marketable securities as of December 31, 2025 consisted of money market mutual funds, U.S. government and agency securities and corporate bonds. If market interest rates were to increase immediately and uniformly by 100 basis points, or one percentage point, from levels at December 31, 2025, we estimate that the increase would have resulted in a hypothetical decline of $0.8 million in the net fair value of our interest-sensitive securities as of December 31, 2025. A similar increase in market interest rates as of December 31, 2024 would have resulted in an estimated hypothetical decline of $0.8 million in the net fair value of our interest-sensitive securities as of December 31, 2024. Foreign Currency Exchange Rate Risk We are exposed to foreign currency exchange rate risk as a result of entering into transactions denominated in currencies other than U.S. dollars, primarily including euros and British pounds. All foreign currency transactions settle on the applicable spot exchange basis at the time such payments are made. Accordingly, an adverse movement in foreign exchange rates between the U.S. dollar and the aforementioned currencies could impact our results of operations and cash flows. Currently, we do not hedge these foreign currency exchange rate exposures. The effect of a hypothetical 10% change in foreign currency exchange rates applicable to our business would not materially harm our business, financial condition or results of operations. ITEM 8. FINANCIAL STATEMEN TS AND SUPPLEMENTARY DATA The financial statements and related financial statement schedules required to be filed are listed in the Index to Consolidated Financial Statements and are incorporated herein. ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOU NTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE None. ITEM 9A. CONTROL S AND PROCEDURES Conclusion Regarding the Effectiveness of Disclosure Controls and Procedures Our management, with the participation of our Chief Executive Officer and our Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2025. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the Exchange Act), means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer concluded that, as of December 31, 2025, our disclosure controls and procedures were effective at a reasonable assurance level. 88 Table of Contents Management’s Report on Internal Control over Financial Reporting Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) promulgated under the Exchange Act as a process designed by, or under the supervision of, our principal executive and principal financial officers and effected by our Board of Directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that: • pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of our assets; • provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that our receipts and expenditures are being made only in accordance with authorizations of our management and directors; and • provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on the financial statements. Under the supervision and with the participation of management, including our principal executive and financial officers, we assessed our internal control over financial reporting as of December 31, 2025, based on criteria for effective internal control over financial reporting established in Internal Control — Integrated Framework (2013), issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). In our management’s opinion, we have maintained effective internal control over financial reporting as of December 31, 2025, based on criteria established in the COSO 2013 framework. As a non-accelerated filer as defined in Rule 12b-2 under the Exchange Act, our independent registered public accounting firm is not required to issue an attestation report on our internal control over financial reporting and no such report is included in this Annual Report on Form 10-K. Changes in Internal Control over Financial Reporting There were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the quarter ended December 31, 2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting. Limitations on the Effectiveness of Controls Control systems, no matter how well conceived and operated, are designed to provide a reasonable, but not an absolute, level of assurance that the objectives of the control system are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, have been detected. Because of the inherent limitations in any control system, misstatements due to error or fraud may occur and not be detected. 89 Table of Contents ITEM 9B. OTHER INFORMATION Rule 10b5-1 Trading Plans The adoption or termination of contracts, instructions or written plans for the purchase or sale of our securities by our Section 16 officers and directors for the three months ended December 31, 2025, each of which is intended to satisfy the affirmative defense of Rule 10b5-1(c) (Rule 10b5-1 Plan), were as follows: Rule 10b5-1 Trading Plan Aggregate # of Provides for Securities to be Name Title Action Date Adopted Expiration Date Purchase/Sale Purchased/Sold (a) Stephen Pakola, M.D. Executive Vice President, Chief Medical Officer Adoption 11/12/2025 12/31/2026 Sale 408,835 (a) The aggregate number of shares in this column includes shares that may be forfeited or withheld to satisfy exercise price and/or tax withholding obligations at the time of vesting. Other than as described above, during the three months ended December 31, 2025, none of our directors or Section 16 reporting officers adopted or terminated any Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement (as such terms are defined in Item 408 of the SEC's Regulation S-K). Amendment to Bylaws On March 4, 2026, the Board of Directors amended and restated the Company’s bylaws (as so amended and restated, the Amended and Restated Bylaws), effective immediately. The Amended and Restated Bylaws modify the Company’s prior bylaws to (i) revise the procedures and disclosure requirements governing stockholder nominations of director candidates, including to require compliance with Rule 14a-19 under the Exchange Act, (ii) update procedures and rules relating to stockholder meetings, (iii) make certain changes to conform to recent amendments to the Delaware General Corporation Law and (iv) make certain other ministerial and conforming changes. The foregoing summary is not, nor is it intended to be, a complete or comprehensive summary of all of the changes reflected in Amended and Restated Bylaws. The foregoing summary is qualified in its entirety by the full text of the Amended and Restated Bylaws, a copy of which is filed as Exhibit 3.2 hereto and incorporated herein by reference. ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS Not applicable. 90 Table of Contents PART III ITEM 10. DIRECTORS, EXECUTIVE OF FICERS AND CORPORATE GOVERNANCE The information required by this item will be included in our proxy statement for the 2026 annual meeting of stockholders to be filed with the SEC within 120 days of the fiscal year ended December 31, 2025 (2026 Proxy Statement) under the headings “Election of Directors,” “Information about our Executive Officers” and “Corporate Governance” and is incorporated herein by reference. We maintain a code of business conduct and ethics that qualifies as a “code of ethics” under Item 406 of the SEC’s Regulation S-K and applies to each of our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer and controller, or persons performing similar functions. The code of business conduct and ethics is available in the corporate governance section of our corporate website at www.regenxbio.com. Any amendment or waiver of the “code of ethics” provisions of the code of business conduct and ethics for an executive officer or director may be granted only by our Board of Directors or a committee thereof and must be timely disclosed as required by applicable law. We intend to satisfy the disclosure requirements regarding any such amendment or waiver applicable to any principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, in a current report filed with the SEC on Form 8-K or on our corporate website at www.regenxbio.com. ITEM 11. EXECUTI VE COMPENSATION The information required by this item will be included in our 2026 Proxy Statement under the headings “Corporate Governance,” “Director Compensation” and “Executive Compensation” and is incorporated herein by reference. ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OW NERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS The information required by this item will be included in our 2026 Proxy Statement under the headings “Executive Compensation” and “Security Ownership of Certain Beneficial Owners and Management” and is incorporated herein by reference. ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE The information required by this item will be included in our 2026 Proxy Statement under the headings “Certain Relationships and Related Party Transactions” and “Corporate Governance” and is incorporated herein by reference. ITEM 14. PRINCIPAL ACCOU NTANT FEES AND SERVICES The information required by this item will be included in our 2026 Proxy Statement under the heading “Ratification of Appointment of Independent Registered Public Accounting Firm” and is incorporated herein by reference. 91 Table of Contents PART IV ITEM 15. EXHIBITS, FINAN CIAL STATEMENT SCHEDULES (a) The following documents are filed as part of, or incorporated by reference into, this Annual Report on Form 10-K: 1. Financial Statements. See Index to Consolidated Financial Statements under Item 8 of this Annual Report on Form 10-K. 2. Financial Statement Schedules. All schedules have been omitted because the information required to be presented in them is not applicable or is shown in the financial statements or related notes. 3. Exhibits. We have filed, or incorporated into this Annual Report on Form 10-K by reference, the exhibits listed on the accompanying Exhibit Index immediately following the financial statements in this Annual Report on Form 10-K. (b) Exhibits. See Item 15(a)(3) above. (c) Financial Statement Schedules. See Item 15(a)(2) above. ITEM 16. FORM 10-K SUMMARY Not applicable. 92 Table of Contents REGENXBIO INC. INDEX TO CONSOLIDATED FINANC IAL STATEMENTS Page Report of Independent Registered Public Accounting Firm (PCAOB ID: 238 ) 94 Consolidated Financial Statements: Consolidated Balance Sheets 96 Consolidated Statements of Operations and Comprehensive Loss 97 Consolidated Statements of Stockholders’ Equity 98 Consolidated Statements of Cash Flows 99 Notes to Consolidated Financial Statements 100 93 Table of Contents Report of Independent Re gistered Public Accounting Firm To the Board of Directors and Stockholders of REGENXBIO Inc. Opinion on the Financial Statements We have audited the accompanying consolidated balance sheets of REGENXBIO Inc. and its subsidiaries (the "Company") as of December 31, 2025 and 2024, and the related consolidated statements of operations and comprehensive loss, of stockholders’ equity and of cash flows for the years then ended, including the related notes (collectively referred to as the "consolidated financial statements"). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for the years then ended in conformity with accounting principles generally accepted in the United States of America. Substantial Doubt about the Company's Ability to Continue as a Going Concern The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 1 to the consolidated financial statements, the Company has incurred cumulative losses from operations since inception, an accumulated deficit of $1.13 billion and cash outflows from operating activities that raise substantial doubt about its ability to continue as a going concern. Management's plans in regard to these matters are also described in Note 1. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Basis for Opinion These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits of these consolidated financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion. Critical Audit Matters The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates. 94 Table of Contents Revenue Recognition – Determination of the Standalone Selling Price of the RGX-121 Intellectual Property License for the United States Under the Nippon Shinyaku Collaboration Agreement As described in Notes 2 and 10 to the consolidated financial statements, the Company’s license agreements are accounted for as contracts with customers within the scope of ASC 606, with the exception of transactions for which the counterparty is determined not to be a customer. The transaction price for each license agreement is allocated to the underlying performance obligations based on their relative standalone selling prices and recognized as revenue when (or as) the performance obligations are satisfied. In January 2025, the Company entered into a collaboration and license agreement with Nippon Shinyaku Co., Ltd. (Nippon Shinyaku) for the development and commercialization of RGX-121, the Company’s product candidate for the treatment of Mucopolysaccharidosis Type II (MPS II), and RGX-111, the Company's product candidate for the treatment of Mucopolysaccharidosis Type I (MPS I) (the Nippon Shinyaku Collaboration Agreement). Management identified the following performance obligations under the agreement: (i) delivery of intellectual property licenses to develop and commercialize RGX-121 and RGX-111 in the United States and Asia territories, (ii) development services for RGX-121 and RGX-111 in the United States, including manufacturing of clinical supply and commercial supply prior to regulatory approval, and (iii) material rights granted to Nippon Shinyaku to purchase commercial supply for sales in licensed territories. The selling prices of intellectual property licenses were determined based on discounted cash flow models for each of the licensed products in the respective licensed territories and were adjusted for the probability of developmental, regulatory and commercial success. Significant assumptions and judgments were required to estimate the future cash flows, including the addressable market, sales price per unit, discount rates and probabilities of success for each of the licensed products and territories. For the year ended December 31, 2025, the Company recognized total revenues of $84.7 million related to the Nippon Shinyaku Collaboration Agreement, of which a majority related to the RGX-121 intellectual property license for the United States. The principal considerations for our determination that performing procedures relating to the determination of the standalone selling price of the RGX-121 intellectual property license for the United States under the Nippon Shinyaku Collaboration Agreement is a critical audit matter are (i) the significant judgment by management when determining the standalone selling price of the RGX-121 intellectual property license for the United States; (ii) a high degree of auditor judgment, subjectivity, and effort in performing procedures and evaluating management’s significant assumptions related to the addressable market, sales price per unit, discount rate and probability of success; and (iii) the audit effort involved the use of professionals with specialized skill and knowledge. Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included, among others (i) reading the contractual terms of the Nippon Shinyaku Collaboration Agreement; (ii) testing management’s process for determining the standalone selling price of the RGX-121 intellectual property license for the United States; (iii) evaluating the appropriateness of the discounted cash flow model; and (iv) evaluating the reasonableness of the significant assumptions used by management related to the addressable market, sales price per unit, discount rate and probability of success. Evaluating the reasonableness of management’s assumptions related to the addressable market, sales price per unit, and the probability of success involved considering (i) the consistency with external market and industry data and (ii) whether the assumptions were consistent with evidence obtained in other areas of the audit. Professionals with specialized skill and knowledge were used to assist in evaluating (i) the appropriateness of the discounted cash flow model and (ii) the reasonableness of the discount rate assumption. /s/ PricewaterhouseCoopers LLP Washington, District of Columbia March 5, 2026 We have served as the Company’s auditor since 2015. 95 Table of Contents REGENXBIO INC. CONSOLIDATED BALANCE SHEETS (in thousands, except per share data) As of December 31, 2025 2024 Assets Current assets Cash and cash equivalents $ 34,466 $ 57,526 Marketable securities 195,604 177,161 Accounts receivable 26,379 20,473 Prepaid expenses 11,927 9,067 Other current assets 12,905 13,774 Total current assets 281,281 278,001 Marketable securities 10,785 10,179 Accounts receivable 2,312 474 Property and equipment, net 104,855 117,589 Operating lease right-of-use assets 47,156 53,716 Restricted cash 2,030 2,030 Other assets 4,613 4,000 Total assets $ 453,032 $ 465,989 Liabilities and Stockholders’ Equity Current liabilities Accounts payable $ 21,358 $ 22,798 Accrued expenses and other current liabilities 38,390 38,070 Deferred revenue 10,452 115 Operating lease liabilities 8,286 7,902 Royalty monetization liabilities 39,609 34,309 Total current liabilities 118,095 103,194 Deferred revenue 18,943 — Operating lease liabilities 65,215 74,131 Royalty monetization liabilities 147,408 25,378 Other liabilities 638 3,635 Total liabilities 350,299 206,338 Commitments and contingencies (Note 8) Stockholders’ equity Preferred stock; $ 0.0001 par value; 10,000 shares authorized, no shares issued and outstanding at December 31, 2025 and 2024 — — Common stock; $ 0.0001 par value; 100,000 shares authorized at December 31, 2025 and 2024; 50,892 and 49,549 shares issued and outstanding at December 31, 2025 and 2024, respectively 5 5 Additional paid-in capital 1,229,442 1,192,536 Accumulated other comprehensive loss ( 687 ) ( 741 ) Accumulated deficit ( 1,126,027 ) ( 932,149 ) Total stockholders’ equity 102,733 259,651 Total liabilities and stockholders’ equity $ 453,032 $ 465,989 The accompanying notes are an integral part of these consolidated financial statements. 96 Table of Contents REGENXBIO INC. CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (in thousands, except per share data) Years Ended December 31, 2025 2024 Revenues License and royalty revenue $ 156,267 $ 81,960 Service revenue 14,174 1,368 Total revenues 170,441 83,328 Operating Expenses Cost of license and royalty revenues 20,298 33,567 Research and development 228,299 208,522 General and administrative 82,863 76,619 Credit losses (recoveries) — ( 5,000 ) Impairment of long-lived assets — 2,101 Other operating expenses 179 865 Total operating expenses 331,639 316,674 Loss from operations ( 161,198 ) ( 233,346 ) Other Income (Expense) Interest income from licensing 83 174 Investment income 12,245 18,729 Interest expense ( 45,008 ) ( 12,659 ) Total other income (expense) ( 32,680 ) 6,244 Net loss $ ( 193,878 ) $ ( 227,102 ) Other Comprehensive Income Unrealized gain on available-for-sale securities, net 54 3,688 Total other comprehensive income 54 3,688 Comprehensive loss $ ( 193,824 ) $ ( 223,414 ) Net loss per share, basic and diluted $ ( 3.76 ) $ ( 4.59 ) Weighted-average common shares outstanding, basic and diluted 51,573 49,509 The accompanying notes are an integral part of these consolidated financial statements. 97 Table of Contents REGENXBIO INC. CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (in thousands) Accumulated Additional Other Total Common Stock Paid-in Comprehensive Accumulated Stockholders’ Shares Amount Capital Loss Deficit Equity Balances at December 31, 2023 44,046 $ 4 $ 1,021,214 $ ( 4,429 ) $ ( 705,047 ) $ 311,742 Vesting of restricted stock units, net of tax 345 — ( 910 ) — — ( 910 ) Exercise of stock options, net of tax 291 — 1,512 — — 1,512 Issuance of common stock under employee stock purchase plan 105 — 1,191 — — 1,191 Issuance of common stock and pre-funded warrants upon public offering, net of transaction costs of $ 534 4,565 1 131,066 — — 131,067 Exercise of pre-funded warrants 197 — — — — — Stock-based compensation expense — — 38,463 — — 38,463 Unrealized gain on available-for-sale securities, net — — — 3,688 — 3,688 Net loss — — — — ( 227,102 ) ( 227,102 ) Balances at December 31, 2024 49,549 5 1,192,536 ( 741 ) ( 932,149 ) 259,651 Vesting of restricted stock units, net of tax 662 — ( 633 ) — — ( 633 ) Exercise of stock options, net of tax 68 — 318 — — 318 Issuance of common stock under employee stock purchase plan 158 — 1,048 — — 1,048 Issuance of warrants, net of transaction costs — — 1,610 — — 1,610 Exercise of pre-funded warrants 455 — — — — — Stock-based compensation expense — — 34,563 — — 34,563 Unrealized gain on available-for-sale securities, net — — — 54 — 54 Net loss — — — — ( 193,878 ) ( 193,878 ) Balances at December 31, 2025 50,892 $ 5 $ 1,229,442 $ ( 687 ) $ ( 1,126,027 ) $ 102,733 The accompanying notes are an integral part of these consolidated financial statements. 98 Table of Contents REGENXBIO INC. CONSOLIDATED STATEMENTS OF CASH FLOWS (in thousands) Years Ended December 31, 2025 2024 Cash flows from operating activities Net loss $ ( 193,878 ) $ ( 227,102 ) Adjustments to reconcile net loss to net cash used in operating activities Stock-based compensation expense 34,563 38,463 Depreciation and amortization 15,615 16,215 Provision for credit losses (recoveries) — ( 5,000 ) Net accretion of discounts on marketable debt securities ( 5,479 ) ( 4,144 ) Net realized gain on investments ( 62 ) ( 6,616 ) Impairment of long-lived assets — 2,101 Non-cash interest expense 12,901 6,101 Other non-cash adjustments 597 1,324 Changes in operating assets and liabilities Accounts receivable ( 7,661 ) 9,707 Prepaid expenses ( 2,860 ) 5,453 Other current assets 658 6,511 Operating lease right-of-use assets 6,653 6,196 Other assets ( 613 ) 807 Accounts payable ( 2,284 ) ( 292 ) Accrued expenses and other current liabilities 229 ( 12,124 ) Deferred revenue 29,280 ( 33 ) Operating lease liabilities ( 8,625 ) ( 8,083 ) Other liabilities ( 2,997 ) ( 2,609 ) Net cash used in operating activities ( 123,963 ) ( 173,125 ) Cash flows from investing activities Purchases of marketable debt securities ( 332,630 ) ( 190,139 ) Maturities of marketable debt securities 319,114 290,238 Sales of equity securities 62 5,783 Purchases of property and equipment ( 2,414 ) ( 2,436 ) Net cash provided by (used in) investing activities ( 15,868 ) 103,446 Cash flows from financing activities Proceeds from exercise of stock options 318 1,512 Taxes paid related to net settlement of stock-based awards ( 633 ) ( 910 ) Proceeds from issuance of common stock under employee stock purchase plan 1,048 1,191 Proceeds from public offering of common stock and pre-funded warrants, net of issuance costs — 131,067 Expenses related to at-the-market offering programs ( 357 ) ( 323 ) Proceeds from issuance of royalty bond and warrants, net of transaction costs 144,493 — Repayments under royalty monetization liabilities, net of interest ( 28,098 ) ( 39,854 ) Net cash provided by financing activities 116,771 92,683 Net increase (decrease) in cash and cash equivalents and restricted cash ( 23,060 ) 23,004 Cash and cash equivalents and restricted cash Beginning of period 59,556 36,552 End of period $ 36,496 $ 59,556 Supplemental cash flow information Cash paid (received) for income taxes $ 285 $ ( 72 ) Cash paid for interest under royalty monetization liabilities $ 32,107 $ 6,559 Supplemental disclosures of non-cash investing and financing information Purchases of property and equipment in accounts payable and accrued expenses and other current liabilities $ 889 $ 339 Deferred equity offering costs in accounts payable and accrued expenses and other current liabilities $ 153 $ 222 Deferred equity offering costs reclassified $ 499 $ 628 The accompanying notes are an integral part of these consolidated financial statements. 99 Table of Contents REGENXBIO INC. NOTES TO CONSOLIDATED FINANC IAL STATEMENTS 1. Nature of Business REGENXBIO Inc. (the Company) is a clinical-stage biotechnology company seeking to improve lives through the curative potential of gene therapy. The Company's investigational gene therapies use adeno-associated virus (AAV) vectors from its proprietary gene delivery platform (NAV Technology Platform). The NAV ® Technology Platform has consisted of exclusive rights to a large portfolio of proprietary AAV vectors. The Company has developed a broad pipeline of gene therapy product candidates using the NAV Technology Platform as a one-time treatment to address an array of diseases. The Company's lead product candidates include ABBV-RGX-314 for the treatment of wet age-related macular degeneration (wet AMD) and diabetic retinopathy (DR), RGX-202 for the treatment of Duchenne muscular dystrophy, RGX-121 for the treatment of Mucopolysaccharidosis Type II (MPS II) and RGX-111 for the treatment of Mucopolysaccharidosis Type I (MPS I). In addition to its internal product development efforts, the Company has also selectively licensed the NAV Technology Platform and other intellectual property rights to other leading biotechnology and pharmaceutical companies (NAV Technology Licensees). As of December 31, 2025, the NAV Technology Platform was being applied by NAV Technology Licensees in two commercial products, Zolgensma ® and Itvisma ® , and in the preclinical and clinical development of various other licensed products. Additionally, the Company has licensed intellectual property rights to collaborators for the joint development and commercialization of certain product candidates. The Company was formed in 2008 in the State of Delaware and is headquartered in Rockville, Maryland. Liquidity The Company has incurred cumulative losses since inception and as of December 31, 2025, had generated an accumulated deficit of $ 1.13 billion. The Company's ability to transition to recurring profitability is dependent upon achieving a level of revenues adequate to support its cost structure, which depends heavily on the successful development, approval and commercialization of its product candidates. The Company may never achieve recurring profitability, and unless and until it does, will continue to need to raise additional capital through equity offerings, licensing and collaboration arrangements, or other non-dilutive financings. There is no assurance that the Company will be able to raise sufficient capital or obtain financing on favorable terms, or at all. As of December 31, 2025, the Company had cash, cash equivalents and marketable securities of $ 240.9 million, which management believes is sufficient to fund operations into early 2027. This estimate is based on the Company's current operating plan, and excludes the potential effects of any future financings or material milestone payments that may be received under the Company's licensing and collaboration arrangements. The Company has based this estimate on assumptions that may prove to be wrong, and it could exhaust its capital resources sooner than expected. These conditions raise substantial doubt about the Company's ability to continue as a going concern within 12 months from the date these consolidated financial statements were issued. The Company’s ability to continue as a going concern will depend heavily on the successful development, approval and commercialization of its product candidates and its ability to raise additional capital to fund its operations. If the Company is unable to raise capital sufficient to meet its working capital needs in the future, it may be forced to delay expenditures, reduce the scope of its development activities or make other changes to its operating plans. 2. Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP) and include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Foreign Currency Transactions The functional currency of the Company and its consolidated subsidiaries is the U.S. dollar. Transaction gains and losses that arise from exchange rate fluctuations on transactions denominated in currencies other than the U.S. dollar are included in results of operations as incurred. During the years ended December 31, 2025 and 2024 , the Company recorded aggregate net foreign currency transaction losses of $ 0.1 million and $ 0.9 million, respectively, which are included in other operating expenses in the consolidated statements of operations and comprehensive loss. 100 Table of Contents Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and related disclosure of contingent assets and liabilities for the periods presented. Management bases its estimates on historical experience and various other factors that it believes are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities, and other reported amounts, that are not readily apparent from other sources. Actual results may differ materially from these estimates. Estimates are used in the following areas, among others: revenue recognition, the allowance for credit losses, accrued research and development expenses and other accrued liabilities, stock-based compensation expense, interest expense under royalty monetization liabilities, income taxes and fair value measurements. Reclassifications Certain amounts reported in prior periods have been reclassified to conform to current period financial statement presentation, including separate presentation of service revenue in the statements of operations and comprehensive loss. As a result of the Company's collaboration and license agreement with Nippon Shinyaku Co., Ltd. (Nippon Shinyaku) which became effective in March 2025, the Company has modified the presentation of its revenues and now presents service revenues separately from license and royalty revenues. The modified presentation has been applied retrospectively to all prior periods presented. The reclassifications have no effect on previously reported financial position, results of operations and cash flows. Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents. Restricted Cash Restricted cash consists of deposits held at financial institutions that are used to collateralize irrevocable letters of credit required under the Company’s lease agreements and certain other agreements with third parties. The following table provides a reconciliation of cash and cash equivalents and restricted cash as reported on the consolidated balance sheets to the total of these amounts as reported at the end of the period in the consolidated statements of cash flows (in thousands): As of December 31, 2025 2024 Cash and cash equivalents $ 34,466 $ 57,526 Restricted cash 2,030 2,030 Total cash and cash equivalents and restricted cash $ 36,496 $ 59,556 Marketable Securities Marketable securities consist of available-for-sale debt securities and are carried at fair value. Marketable debt securities with remaining maturity dates exceeding 12 months which are not intended to be sold prior to maturity for use in current operations are classified as non-current assets. Unrealized gains and losses on available-for-sale debt securities, net of any related tax effects, are excluded from results of operations and are included in other comprehensive income and reported as a separate component of stockholders’ equity until realized. The Company uses the aggregate portfolio approach to release the tax effects of unrealized gains and losses on available-for-sale debt securities in accumulated other comprehensive loss. Purchase premiums and discounts on marketable debt securities are amortized or accreted into the cost basis over the life of the related security as adjustments to the yield using the effective-interest method. Interest income is recognized when earned. Realized gains and losses from the sale or maturity of marketable securities are based on the specific identification method and are included in results of operations as investment income. At each reporting date, the Company evaluates available-for-sale debt securities which have an amortized cost basis in excess of the fair value of the security to determine if the unrealized loss or any potential credit losses should be recognized in results of operations. If the Company does not have the intent and ability to hold the security until recovery of the unrealized loss, the difference between the fair value and amortized cost basis of the security is charged to results of operations resulting in a new amortized cost basis of the security. If the Company has the intent and ability to hold the security until recovery of the unrealized loss, the security is evaluated for potential credit losses. If a credit loss is deemed to exist, the credit loss is recognized in results of operations and an allowance for credit losses is recorded against the amortized cost basis of the security. In determining whether a credit loss exists related to impaired available-for-sale debt securities, the Company considers, among other factors, the extent of the unrealized loss relative to the amortized cost basis, the credit rating of the issuer and any recent changes thereto, current and expected future 101 Table of Contents economic conditions, and any adverse events or other changes in circumstances that have occurred which may indicate a potential credit loss. The Company did not record an allowance for credit losses on its available-for-sale debt securities as of December 31, 2025 or 2024. Accounts Receivable Accounts receivable consist of consideration due to the Company resulting from its agreements with customers. Accounts receivable include amounts invoiced to customers as well as rights to consideration which have not yet been invoiced, including unbilled royalties and services, and for which payment is conditional solely upon the passage of time. If a licensee elects to terminate a license prior to the end of the license term, the licensed intellectual property is returned to the Company and any accounts receivable from the licensee which are not contractually payable to the Company are charged off as a reduction of revenue in the period of the termination. Accounts receivable which are not expected to be received by the Company within 12 months from the reporting date are stated net of a discount to present value and recorded as non-current assets on the consolidated balance sheets. The present value discount is recognized as a reduction of revenue in the period in which the accounts receivable balance is initially recorded and is accreted as interest income from licensing over the term of the receivables. Accounts receivable are stated net of an allowance for credit losses, if deemed necessary based on the Company’s evaluation of collectability and potential credit losses. Management assesses the collectability of its accounts receivable using the specific identification of account balances and considers the credit quality and financial condition of its significant customers, historical information regarding credit losses and the Company’s evaluation of current and expected future economic conditions. If necessary, an allowance for credit losses is recorded against accounts receivable such that the carrying value of accounts receivable reflects the net amount expected to be collected. Accounts receivable balances are written off against the allowance for credit losses when the potential for collectability is considered remote. The Company did not record an allowance for credit losses on its accounts receivable as of December 31, 2025 or 2024. Concentrations of Credit Risk and Off-balance Sheet Risk Cash and cash equivalents, marketable debt securities and accounts receivable are financial instruments that are potentially subject to concentrations of credit risk. The Company’s cash and cash equivalents are deposited in accounts at multiple financial institutions, and amounts may exceed federally insured limits. The Company believes it is not exposed to significant credit risk due to the financial strength of the depository institutions in which the cash and cash equivalents are held. The Company’s marketable debt securities consist of investment grade securities and may be subject to concentrations of credit risk. The Company has adopted an investment policy which limits potential concentrations of investments and establishes minimum acceptable credit ratings, thereby reducing credit risk exposure. As of December 31, 2025, the Company believes that it is not exposed to significant credit risk related to accounts receivable due to the credit quality and history of collections from its significant customers, and the Company is unaware of any concentrations of credit risk related to accounts receivable from significant customers with deteriorated credit quality. The Company has no financial instruments with off-balance sheet risk of loss. The following table summarizes those customers who represented at least 10% of revenues or total net accounts receivable for the periods presented: Revenues Accounts Receivable Years Ended December 31, As of December 31, 2025 2024 2025 2024 Customer A 49 % 98 % 84 % 97 % Customer B 50 % — 14 % — Leases The Company accounts for its lease arrangements in accordance with Accounting Standards Codification (ASC) 842, Leases (ASC 842). Under ASC 842, the Company classifies its leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the Company. Lease classification is evaluated at the inception of the lease agreement. Regardless of classification, the Company records a right-of-use asset and a lease liability for all leases with a term greater than 12 months. All of the Company’s leases are classified as operating leases. Operating lease expense is recognized on a straight-line basis over the term of the lease, with the exception of variable lease expenses which are recognized as incurred. 102 Table of Contents The Company identifies leases in its contracts if the contract conveys the right to control the use of identified property, plant or equipment for a period of time in exchange for consideration. The Company does not allocate lease consideration between lease and nonlease components and records a lease liability equal to the present value of the remaining fixed consideration under the lease. The interest rates implicit in the Company’s leases are generally not readily determinable. Accordingly, the Company uses its estimated incremental borrowing rate at the commencement date of the lease to determine the present value discount of the lease liability. The Company estimates its incremental borrowing rate for each lease based on an evaluation of its expected credit rating and the prevailing market rates for collateralized debt in a similar economic environment with similar payment terms and maturity dates commensurate with the term of the lease. The right-of-use asset for each lease is equal to the lease liability, adjusted for unamortized initial direct costs and lease incentives and prepaid or accrued rent. Initial direct costs of entering into a lease are included in the right-of-use asset and amortized as lease expense over the term of the lease. Lease incentives, such as tenant improvement allowances, are recorded as a reduction of the right-of-use asset and amortized as a reduction of lease expense over the term of the lease. The Company excludes options to extend or terminate leases from the calculation of the lease liability unless it is reasonably certain the option will be exercised. The Company evaluates its right-of-use assets for impairment in accordance with its policy for long-lived assets. To the extent an impairment of a right-of-use asset is recognized, the remaining carrying value of the asset is subsequently amortized as lease expense on a straight-line basis from the date of impairment to the earlier of the end of the right-of-use asset’s useful life or the end of the lease term. The Company determines the classification of subleases at the inception of the sublease, as well as whether the Company has been relieved of its primary obligation under the original lease. All of the Company's subleases are classified as operating leases and, in each case, the Company has not been relieved of its primary obligation under the original lease and continues to account for the original lease as it did prior to the commencement of the sublease. Sublease income is recognized on a straight-line basis over the term of the sublease as a reduction of the related lease expense of the original lease. Initial direct costs of entering into a sublease are deferred and amortized on a straight-line basis over the term of the sublease as a reduction of sublease income. Property and Equipment Property and equipment is stated at cost less accumulated depreciation and amortization. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred. Upon disposal, the related cost and accumulated depreciation is removed from the accounts and any resulting gain or loss is included in the results of operations. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the assets, which are as follows: Estimated Useful Life Computer equipment and software 3 years Furniture and fixtures 5 years Laboratory and manufacturing equipment 5 to 15 years Leasehold improvements Shorter of lease term or estimated useful life Cloud Computing Arrangements The Company capitalizes certain costs associated with the implementation of cloud computing arrangements that are accounted for as service contracts. Once implementation activities are substantially complete and the cloud-based application is ready for its intended use, capitalization ceases and amounts capitalized are amortized on a straight-line basis over the term of the hosting arrangement. Capitalized implementation costs for cloud-based applications and associated amortization are classified on the consolidated balance sheets and statements of operations and comprehensive loss in the same manner as the costs of the associated hosting arrangement. As of December 31, 2025 and 2024, the Company had recorded capitalized costs, net of amounts amortized, of $ 0.1 million and less than $ 0.1 million, respectively, related to the implementation of cloud-based software applications, which were included in prepaid expenses and other assets on the consolidated balance sheets. Amortization of capitalized implementation costs for cloud-based applications recorded for the years ended December 31, 2025 and 2024 was less than $ 0.1 million and $ 1.0 million, respectively, and was included in general and administrative expenses in the consolidated statements of operations and comprehensive loss. 103 Table of Contents Impairment of Long-lived Assets The Company's long-lived assets consist primarily of property and equipment and operating lease right-of-use assets. The Company evaluates its long-lived assets for impairment when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparison of the book values of the assets to estimated future net undiscounted cash flows that the assets are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the book value of the assets exceed their fair value, which is measured based on the projected discounted future net cash flows arising from the assets. Please refer to Note 5 and Note 6 for further information on impairment of long-lived assets. Non-marketable Equity Securities Non-marketable equity securities consist of equity investments in other entities in which the Company’s ownership interest is below 20 % and the Company does not have significant influence over the operations of the entity, or for which the equity securities are not common stock or in-substance common stock. The Company’s non-marketable equity securities do not have readily determinable fair values and are measured at cost less impairment, adjusted for observable price changes for identical or similar investments of the same issuer. Please refer to Note 3 for further information on non-marketable equity securities. Fair Value Measurements The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC 820, Fair Value Measurements and Disclosures , establishes a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. • Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly. • Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for assets and liabilities categorized in Level 3. The level within the fair value hierarchy of an asset or liability measured at fair value is based on the lowest level of any input that is significant to the fair value measurement. The fair values of the Company’s Level 2 financial instruments are based on quoted market prices or broker or dealer quotations for similar assets. These investments are initially valued at the transaction price and subsequently valued utilizing third-party pricing providers or other market observable data. Please refer to Note 4 for further information on the Company's fair value measurements. Royalty Monetization Liabilities As discussed in Note 7, the Company has entered into multiple royalty monetization arrangements with entities managed by Healthcare Royalty Management, LLC (collectively and with other affiliated entities, HCR). Net proceeds received by the Company under these arrangements are recorded as liabilities and accounted for as debt since the return to HCR is explicitly capped under the agreements. The liabilities are amortized over the estimated life of the arrangements using the effective interest method. For arrangements in which there is no stated interest rate, the total amount of royalty and other payments paid to HCR under the arrangement, less the net proceeds received by the Company, is recorded as interest expense over the life of the arrangement. The Company estimates the effective interest rates of its royalty monetization liabilities based on its estimate of total payments to be paid to HCR under the arrangements. The Company reassesses these estimates at each reporting date and adjusts the effective interest rate and amortization of the liabilities on a prospective basis as necessary. 104 Table of Contents Due to its continuing involvement in the license and collaboration agreements underlying the royalty monetization arrangements with HCR, the Company continues to recognize license and royalty revenues under these license and collaboration agreements and records any payments to HCR as a reduction of the associated royalty monetization liability when paid. As such payments are made to HCR, the balance of the liability will be effectively repaid over the life of the royalty monetization agreement. The portion of royalty monetization liabilities representing principal that is expected to be paid within 12 months of the reporting date is recorded as a current liability, with the remaining portion of the liabilities recorded as non-current. Warrants Warrants are accounted for based on the specific terms of the warrant agreements. The Company's warrants, including pre-funded warrants, are indexed to the Company's common stock and meet the criteria to be classified as equity. Net proceeds received from the issuance of warrants are recorded within additional paid-in capital and are not subject to remeasurement. Please refer to Note 9 for further information regarding warrants issued by the Company. Revenue Recognition The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers (ASC 606). ASC 606 requires entities to recognize revenue when control of the promised goods or services is transferred to customers at an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The following five steps are performed to determine the appropriate revenue recognition for arrangements within the scope of ASC 606: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract and (v) recognize revenue when (or as) the entity satisfies the performance obligations. The Company applies the five-step model to contracts that are within the scope of ASC 606 only when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, for contracts within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations and whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to respective performance obligations when (or as) the respective performance obligations are satisfied. The Company evaluates its contracts with customers for the presence of significant financing components. If a significant financing component is identified in a contract and provides a financing benefit to the customer, the transaction price for the contract is adjusted to account for the financing portion of the arrangement, which is recognized as interest income over the financing term using the effective interest method. In determining the appropriate interest rates for significant financing components, the Company evaluates the credit profile of the customer and prevailing market interest rates and selects an interest rate in which it believes would be charged to the customer in a separate financing arrangement over a similar financing term. The Company licenses its NAV Technology Platform and other intellectual property rights to other biotechnology and pharmaceutical companies, including collaborators for the joint development and commercialization of its product candidates. The terms of the licenses vary, and licenses may be exclusive or non-exclusive and may be sublicensable by the licensee. Licenses may grant intellectual property rights for purposes of internal and preclinical research and development only, or may include the rights, or options to obtain future rights, to commercialize drug therapies for specific diseases using the Company’s NAV Technology Platform and other licensed rights. License agreements generally have a term at least equal to the life of the underlying patents, but are terminable at the option of the licensee. Consideration payable to the Company under its license and collaboration agreements may include: (i) up-front and annual fees, (ii) milestone payments based on the achievement of certain development and sales-based milestones, (iii) sublicense fees, (iv) royalties on sales of licensed products, (v) fees for services related to the development and manufacturing of licensed products and (vi) other consideration payable upon optional goods and services purchased by licensees and collaborators. The Company evaluates its agreements with collaboration partners to determine whether they are within the scope of ASC 808, Collaborative Arrangements (ASC 808). For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company identifies the various transactions with the counterparty and determines if any unit of account is more reflective of a transaction with a customer and therefore should be accounted for within the scope of ASC 606. For transactions that are accounted for pursuant to ASC 606, the Company applies the five-step model as described in its revenue recognition policies. For transactions that are accounted for pursuant to ASC 808, an appropriate method of recognition and presentation is determined and consistently applied in accordance with the Company's accounting policies for collaborative arrangements. 105 Table of Contents The Company’s license and collaboration agreements are accounted for as contracts with customers within the scope of ASC 606, with the exception of transactions for which the counterparty is determined not to be a customer. At the inception of each agreement, the Company determines the contract term for purposes of applying the requirements of ASC 606. Licenses are generally terminable at the option of the licensee with advance notice to the Company. For each license granted, the Company evaluates these termination rights to determine whether a substantive termination penalty would be incurred by the licensee upon termination. If the licensee incurs a substantive termination penalty upon termination, the contract term for revenue recognition purposes is generally equal to the stated term of the license, which is the life of the underlying licensed patents. Alternatively, if the licensee does not incur a substantive termination penalty upon termination, the contract term for revenue recognition purposes may be shorter than the stated term of the license, in which case the termination rights may be accounted for as contract renewal options. Performance obligations under the Company’s license and collaboration agreements may include (i) the delivery of intellectual property licenses, (ii) development and manufacturing services to be performed by the Company related to licensed products and (iii) options granted to purchase additional goods and services, to the extent the options convey material rights. At the inception of each license agreement which contains performance obligations for development, manufacturing or other services, the Company evaluates whether the license is distinct from the services, which requires judgment. In making this determination, the Company considers, among other things, the stage of development of the licensed products and whether the services will significantly impact further development of the licensed products. If it is determined that the license is not distinct from the services, the license is combined with the services into a single performance obligation. Agreements may provide licensees and collaborators with options to purchase additional goods or other services, including options to purchase commercial supply of licensed products. Options are evaluated at the inception of the agreement to determine whether they provide material rights to the customer. In making this determination, the Company considers whether the options are priced at an incremental discount to the standalone selling price of the underlying goods or services, in which case the option is considered to be a material right. Material rights are accounted for as separate performance obligations under the current arrangement. The Company evaluates the transaction price of its license and collaboration agreements at contract inception and at each reporting date. The transaction price includes the fixed consideration payable to the Company over the contract term, as well as any variable consideration to the extent that it is probable that a significant reversal of revenue will not occur in the future. Fixed consideration under the agreements may include up-front and annual fees payable over the contract term and fixed fees for development, manufacturing and other services performed by the Company. Variable consideration under the agreements may include development and sales-based milestone payments, payments for development, manufacturing and other services performed by the Company, sublicense fees and royalties on sales of licensed products. Consideration contingent upon the exercise of options by the customer is excluded from the transaction price and not accounted for as part of the arrangement until the option is exercised. The transaction price of the Company's license and collaboration arrangements is allocated to the underlying performance obligations based on their relative standalone selling prices and recognized as revenue when (or as) the performance obligations are satisfied. Variable consideration payable based on services performed by the Company is allocated directly to the performance obligation for such services. Consideration allocated to performance obligations for the delivery of intellectual property licenses is recognized as license and royalty revenue in full upon the delivery of the license. Consideration allocated to performance obligations for development, manufacturing and other services is recognized as service revenue as the services are performed by the Company. Consideration allocated to performance obligations for material rights to purchase additional goods and services is recognized as revenue upon the satisfaction of the performance obligations underlying the optional goods and services purchased by the customer. Service revenue is recognized using a measure of progress that best reflects the pattern of satisfaction of the performance obligations. At each reporting date, the Company re-evaluates the measure of progress and adjusts service revenue on a cumulative catch-up basis to reflect its best estimate of the services performed to date versus the total services to be performed under the arrangement. Development milestone payments are payable to the Company upon the achievement of specified development milestones. At the inception of each license agreement that contains development milestone payments, the Company evaluates whether the milestones are probable of achievement and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal will not occur in the future, milestone payments are included in the transaction price. Milestone payments contingent on the achievement of development milestones that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved and are excluded from the transaction price until the milestone is achieved. At each reporting date, the Company re-evaluates the probability of achievement of each outstanding development milestone and, if necessary, adjusts the transaction price for any milestones for which the probability of achievement has changed due to current facts and circumstances. The increase to the transaction price as a result of any such adjustments is then allocated to the underlying performance obligations in a manner similar to the allocation of the initial transaction price and, to the extent the performance obligations are satisfied, recognized as revenue on a cumulative catch-up basis in the period of the adjustment. 106 Table of Contents Royalties on sales of licensed products, sales-based milestone payments, including milestones payable upon first commercial sales of licensed products, and sublicense fees based on the receipt of certain fees by licensees from any sublicensees are excluded from the transaction price of each license and recognized as license and royalty revenue in the period that the related sales or sublicenses occur, provided that the associated license has been delivered to the licensee. Royalty revenue to date consists primarily of royalties on net sales of Zolgensma and Itvisma, which are licensed products under the Company’s license agreement with Novartis Gene Therapies, Inc. (Novartis Gene Therapies), a wholly owned subsidiary of Novartis AG (Novartis), for the development and commercialization of treatments for spinal muscular atrophy (SMA). The Company recognizes royalty revenue from net sales of Zolgensma and Itvisma in the period in which the underlying products are sold by Novartis Gene Therapies, which in certain cases may require the Company to estimate royalty revenue for periods of net sales which have not yet been reported to the Company. Estimated royalties are reconciled to actual amounts reported in subsequent periods, and any differences are recognized as an adjustment to royalty revenue in the period the royalties are reported. The Company receives payments from licensees and collaborators based on the billing schedules established in the associated agreements. Amounts recognized as revenue which have not yet been received from the customer are recorded as accounts receivable when the Company’s rights to the consideration are conditional solely upon the passage of time. Amounts recognized as revenue which have not yet been received from customers are recorded as contract assets when the Company’s rights to the consideration are not unconditional. Contract assets are recorded as other current assets on the consolidated balance sheets if the consideration is expected to be realized within 12 months from the reporting date, or as other assets if the consideration is expected to be realized in periods beyond 12 months from the reporting date. If a licensee elects to terminate a license prior to the end of the license term, the licensed intellectual property is returned to the Company and any consideration recorded as accounts receivable or contract assets which is not contractually payable by the licensee is charged off as a reduction of revenue in the period of the termination. Amounts received by the Company prior to the delivery of underlying performance obligations are deferred and recognized as revenue upon the satisfaction of the performance obligations by the Company. Deferred revenue which is not expected to be recognized within 12 months from the reporting date is recorded as non-current on the consolidated balance sheets. Collaborative Arrangements The Company evaluates its agreements with collaboration partners to determine whether they are within the scope of ASC 808. Such arrangements are within the scope of ASC 808 if they involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. This evaluation is performed throughout the life of the arrangement based on any changes in the roles and responsibilities of the parties under the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company identifies the various transactions with the counterparty and determines if any unit of account is more reflective of a transaction with a customer and therefore should be accounted for within the scope of ASC 606. For transactions that are accounted for pursuant to ASC 606, the Company applies the five-step model as described in its revenue recognition policies. For transactions that are accounted for pursuant to ASC 808, an appropriate method of recognition and presentation is determined and consistently applied. For transactions accounted for as collaborative arrangements under ASC 808, payments to and from collaboration partners associated with multiple activities in a collaboration arrangement are classified based on the nature of each separate activity. Payments associated with development activities performed are recorded as research and development expense when owed to collaboration partners, or as a reduction of research and development expense when due from collaboration partners. Payments associated with commercialization activities performed are recorded as general and administrative expense when owed to collaboration partners, or as a reduction of general and administrative expense when due from collaboration partners. At the end of each reporting period, the Company records a net amount due to or from collaboration partners for activities performed by the parties under the collaboration. Cost of License and Royalty Revenues Cost of license and royalty revenues consists primarily of sublicense fees and royalties on net sales of licensed products as specified in the Company’s agreements with its licensors. Sublicense fees are based on a percentage of license fees received by the Company from licensees and are recognized in the period that the underlying revenue is recognized. Royalties are based on a percentage of net sales of licensed products by licensees and are recognized in the period that the underlying sales occur. Amounts which are payable to licensors in periods beyond 12 months from the reporting date are recorded as non-current liabilities on the consolidated balance sheets. 107 Table of Contents Research and Development Expenses Research and development costs are expensed as incurred in performing research and development activities. Advance payments for goods or services related to research and development activities are deferred and expensed as the goods are delivered or the services are performed. Research and development costs include salaries, wages, benefits and other personnel-related costs, laboratory and facilities costs, allocated overhead costs, license and milestone fees, and costs of goods and services associated with preclinical research and clinical trial activities, associated manufacturing-related activities, regulatory activities and other related services performed by third parties. At the end of each reporting period, the Company compares payments made to third-party service providers to the estimated expenses incurred based on the services provided and progress toward completion of the research or development objectives. Such estimates are subject to change as additional information becomes available. Depending on the timing of payments to the service providers and the estimated expenses incurred, the Company may record net prepaid or accrued research and development expenses relating to these costs. Up-front fees incurred in obtaining technology licenses, as well as milestone payments to licensors, are charged to research and development expense as incurred if the technology licensed has no alternative future use. Stock-based Compensation The Company accounts for its stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation (ASC 718). ASC 718 requires all stock-based awards to employees and nonemployees to be recognized as expense based on the grant date fair value of the awards. The Company’s stock-based awards include stock options and restricted stock units granted to employees and nonemployees and shares issued to employees under its employee stock purchase plan. The Company’s stock-based awards may be subject to either service or performance-based vesting conditions. Compensation expense related to awards with service-based vesting conditions is recognized on a straight-line basis based on the estimated grant date fair value over the requisite service period of the award, which is generally the vesting term. Compensation expense related to awards with performance-based vesting conditions is recognized based on the estimated grant date fair value over the requisite service period using the accelerated attribution method to the extent achievement of the performance condition is probable. The Company has elected to not estimate forfeitures of stock-based awards and accounts for forfeitures as they occur. The Company estimates the fair value of its stock option awards using the Black-Scholes option-pricing model, which requires the input of subjective assumptions, including (i) the fair value of the underlying common stock, (ii) the expected stock price volatility, (iii) the expected term of the award, (iv) the risk-free interest rate and (v) expected dividends. The Company estimates expected stock price volatility based on the historical volatility of its common stock over a period of time commensurate with the expected term of its stock option awards. Due to the lack of sufficient historical data, the Company estimates the expected term of its employee stock options using the “simplified” method, whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. For stock options granted to nonemployees, the Company uses the contractual term of the award rather than expected term to estimate the fair value of the award. The Company estimates the risk-free interest rates for periods within the expected term of its options based on the rates of U.S. Treasury securities with maturity dates commensurate with the expected term of the associated awards. The Company assumes a dividend yield of zero for its common stock as it has never paid dividends and does not expect to pay dividends for the foreseeable future. The Company estimates the fair value of restricted stock units based on the fair value of the Company’s common stock on the date of the grant. Income Taxes Income taxes are accounted for in accordance with ASC 740, Income Taxes (ASC 740), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are provided, if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. 108 Table of Contents The Company recognizes interest and penalties related to uncertain tax positions in income tax expense. As of December 31, 2025 and 2024 , the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company’s consolidated statements of operations and comprehensive loss. Restructuring Expenses The Company records costs and liabilities associated with exit and disposal activities in accordance with ASC 420, Exit or Disposal Cost Obligations (ASC 420) and ASC 712, Compensation – Nonretirement Postemployment Benefits (ASC 712). Such costs are based on estimates of fair value in the period liabilities are incurred. The Company evaluates and adjusts these costs as appropriate for changes in circumstances as additional information becomes available. Please refer to Note 14 for further information regarding restructuring expenses. Net Loss Per Share Basic net loss per share is calculated by dividing net loss applicable to common stockholders by the weighted-average common shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by adjusting the weighted-average common shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of computing both basic and diluted net loss per share, pre-funded warrants are considered outstanding shares upon issuance because the underlying shares may be issued for nominal consideration and are exercisable after the original issuance date. Contingently convertible shares in which conversion is based on non-market-priced contingencies are excluded from the calculations of both basic and diluted net loss per share until the contingency has been fully met. For purposes of the diluted net loss per share calculation, common stock equivalents are excluded from the calculation of diluted net loss per share if their effect would be anti-dilutive. Comprehensive Loss Comprehensive loss includes net loss as well as unrealized gains and losses on available-for-sale debt securities, net of income tax effects and reclassification adjustments for realized gains and losses. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In November 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures , which enhances certain interim and annual disclosure requirements of reportable segment information, including information about significant segment expenses. Additionally, the standard requires entities with a single reportable segment to provide all disclosures required by ASC 280, Segment Reporting . The Company adopted this standard for annual reporting periods beginning January 1, 2024 and interim reporting periods beginning January 1, 2025, on a retrospective basis for all periods presented. Please refer to Note 16 for further information regarding reportable segment information, including the information required to be disclosed pursuant to this standard. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures , which enhances the disclosure of an entity's effective tax rate reconciliation and requires the disclosure of income taxes paid to be disaggregated by jurisdiction. The Company adopted this standard for annual reporting periods beginning January 1, 2025, on a retrospective basis for all periods presented. Please refer to Note 13 for further information regarding income taxes, including the information required to be disclosed pursuant to this standard. Recent Accounting Pronouncements Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses . The new standard requires disclosures about specific types of expenses included in the expense captions presented on the face of the income statement as well as disclosures about selling expenses. In January 2025, the FASB issued ASU 2025-01, which clarifies the effective date of ASU 2024-03 with respect to interim periods. The standard is effective for the Company for annual periods beginning January 1, 2027 and interim periods beginning January 1, 2028, with early adoption permitted. The standard may be applied either prospectively to financial statements issued for reporting periods after the effective date or retrospectively to any or all prior periods presented in the financial statements. The Company is currently in the process of evaluating the impact of this standard on its consolidated financial statements and related disclosures. 109 Table of Contents 3. Marketable Securities and Other Investments The following tables present a summary of the Company’s marketable securities, which consist solely of available-for-sale debt securities (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Fair Value December 31, 2025 U.S. government and agency securities $ 83,085 $ 59 $ — $ 83,144 Corporate bonds 123,131 131 ( 17 ) 123,245 $ 206,216 $ 190 $ ( 17 ) $ 206,389 Amortized Cost Unrealized Gains Unrealized Losses Fair Value December 31, 2024 U.S. government and agency securities $ 44,281 $ 11 $ ( 77 ) $ 44,215 Certificates of deposit 1,466 — ( 4 ) 1,462 Corporate bonds 141,474 234 ( 45 ) 141,663 $ 187,221 $ 245 $ ( 126 ) $ 187,340 As of December 31, 2025 and 2024 , no available-for-sale debt securities had remaining maturities greater than two years. The amortized cost of marketable debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, or to the earliest call date for callable debt securities purchased at a premium. As of December 31, 2025 and 2024, the balance in accumulated other comprehensive loss consisted solely of unrealized gains and losses on available-for-sale debt securities, net of reclassification adjustments for realized gains and losses and income tax effects. The Company did no t recognize any realized gains or losses on available-for-sale securities during the years ended December 31, 2025 and 2024, and no income tax effects or reclassification adjustments were recorded in accumulated other comprehensive loss during the periods. The following tables present the fair values and unrealized losses of available-for-sale debt securities held by the Company in an unrealized loss position for less than 12 months and 12 months or greater (in thousands): Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses December 31, 2025 U.S. government and agency securities $ 4,676 $ — $ — $ — $ 4,676 $ — Corporate bonds 32,289 ( 17 ) — — 32,289 ( 17 ) $ 36,965 $ ( 17 ) $ — $ — $ 36,965 $ ( 17 ) Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses December 31, 2024 U.S. government and agency securities $ — $ — $ 22,917 $ ( 77 ) $ 22,917 $ ( 77 ) Certificates of deposit — — 1,221 ( 4 ) 1,221 ( 4 ) Corporate bonds 21,317 ( 45 ) — — 21,317 ( 45 ) $ 21,317 $ ( 45 ) $ 24,138 $ ( 81 ) $ 45,455 $ ( 126 ) As of December 31, 2025 , available-for-sale debt securities held by the Company in an unrealized loss position consisted of nine investment grade security positions. The Company has the intent and ability to hold such securities until recovery, and based on the credit quality of the issuers and low severity of each unrealized loss position relative to its amortized cost basis, the Company did not identify any credit losses associated with its available-for-sale debt securities. The Company did not recognize any impairment or credit losses on available-for-sale debt securities during the years ended December 31, 2025 and 2024. 110 Table of Contents Non-marketable Equity Securities Non-marketable equity securities are measured at cost less impairment, adjusted for observable price changes for identical or similar investments of the same issuer. The Company did no t hold any non-marketable equity securities as of December 31, 2025 and 2024. No remeasurements or impairment losses were recorded on non-marketable equity securities during the years ended December 31, 2025 and 2024. Prior to the acquisition of Corlieve Therapeutics SAS (Corlieve) by uniQure N.V. (uniQure) in July 2021, the Company held non-marketable equity securities of Corlieve which were originally acquired by the Company in June 2 020 as consideration under a license and collaboration agreement with Corlieve. In connection with the acquisition of Corlieve by uniQure in July 2021, the Company received proceeds of € 5.3 million ($ 6.1 million) from uniQure in exchange for its ownership interest in Corlieve. As additional consideration, the Company became eligible to receive payments of up to € 37.1 million from uniQure contingent upon the achievement of various development and regulatory milestones. During the year ended December 31, 2024, the Company received € 5.6 million in milestone payments from uniQure and recognized investment income of $ 6.6 million, respectively, related to the achievement of the milestones during the period. No milestones were achieved or paid by uniQure during the year ended December 31, 2025. As of December 31, 2025, there were € 29.7 million ($ 35.0 million as of December 31, 2025) in remaining milestones which have not been paid or achieved and have not been recognized in the consolidated financial statements. Proceeds contingent upon the achievement of the remaining milestones will be recognized as investment income in the period in which any uncertainty regarding realization is substantially resolved, which may not occur until the achievement of the underlying milestones. It is at least reasonably possible that some or all of the proceeds contingent upon these milestones will not be realized by the Company. 4. Fair Value Measurements Financial instruments reported at fair value on a recurring basis include cash equivalents and marketable securities. The following tables present the fair value of cash equivalents and marketable securities in accordance with the fair value hierarchy discussed in Note 2 (in thousands): Level 1 Level 2 Level 3 Total December 31, 2025 Cash equivalents: Money market mutual funds $ — $ 21,418 $ — $ 21,418 U.S. government and agency securities — 2,496 — 2,496 Total cash equivalents — 23,914 — 23,914 Marketable securities: U.S. government and agency securities — 83,144 — 83,144 Corporate bonds — 123,245 — 123,245 Total marketable securities — 206,389 — 206,389 Total cash equivalents and marketable securities $ — $ 230,303 $ — $ 230,303 Level 1 Level 2 Level 3 Total December 31, 2024 Cash equivalents: Money market mutual funds $ — $ 43,895 $ — $ 43,895 U.S. government and agency securities — 2,498 — 2,498 Total cash equivalents — 46,393 — 46,393 Marketable securities: U.S. government and agency securities — 44,215 — 44,215 Certificates of deposit — 1,462 — 1,462 Corporate bonds — 141,663 — 141,663 Total marketable securities — 187,340 — 187,340 Total cash equivalents and marketable securities $ — $ 233,733 $ — $ 233,733 Management estimates that the carrying values of its current accounts receivable, other current assets, accounts payable, accrued expenses and other current liabilities approximate fair value due to the short-term nature of those instruments. Certain non-current accounts receivable and non-current payables reported as other liabilities are recorded at their present values using a discount rate that is based on prevailing market rates on the date the amounts were initially recorded. Management does not believe there have been any significant changes in market conditions or credit quality that would cause the discount rates initially used to be materially different 111 Table of Contents from those that would be used as of December 31, 2025 to determine the present value of these instruments. Accordingly, management estimates that the carrying values of its non-current accounts receivable and other liabilities approximate the fair value of those instruments. Management estimates that the carrying values of its royalty monetization liabilities approximate fair value. As discussed in Note 7, the carrying values of royalty monetization liabilities are based on the Company’s estimate of future royalties, milestones and other consideration to be paid over the life of the arrangement, which are considered Level 3 inputs, as well as any remaining repayment obligations upon maturity of the instruments. Long-lived assets, if determined to be impaired, are measured at fair value on a nonrecurring basis using Level 3 inputs. Please refer to Note 6 for further information on nonrecurring fair value measurements of long-lived assets during the years ended December 31, 2025 and 2024. 5. Property and Equipment, Net Property and equipment, net consists of the following (in thousands): As of December 31, 2025 2024 Laboratory and manufacturing equipment $ 78,825 $ 77,141 Computer equipment and software 4,573 4,244 Furniture and fixtures 7,039 7,031 Leasehold improvements 101,610 101,465 Total property and equipment 192,047 189,881 Accumulated depreciation and amortization ( 87,192 ) ( 72,292 ) Property and equipment, net $ 104,855 $ 117,589 During the years ended December 31, 2025 and 2024, the Company recorded depreciation and amortization expense of $ 15.6 million and $ 16.2 million, respectively. In March 2024, the Company entered into an agreement to sublease its office facilities in New York, New York. In connection with the sublease, the Company recorded impairment of property and equipment of $ 0.7 million in the first quarter of 2024 related to furniture and fixtures and leasehold improvements located at the subleased facility. Please refer to Note 6 for further information regarding the sublease agreement and associated impairment of long-lived assets. 6. Leases 9804 Medical Center Drive In November 2018, the Company entered into an operating lease, which has been amended from time to time, for approximately 186,000 square feet of office, laboratory and manufacturing space at 9804 Medical Center Drive in Rockville, Maryland (the 9804 Medical Center Drive Lease), which now serves as the Company’s corporate, research and manufacturing headquarters. The initial construction of the building was performed by the landlord and the lease commenced in September 2020 upon delivery of the leased premises to the Company to make additional improvements to the building. Monthly payments under the lease began in September 2021 and escalate annually in accordance with the lease agreement. The lease expires in September 2036 , subject to extension and termination options held by the Company. The Company has an option to extend the term of the lease for up to 10 additional years and an option to terminate the lease, with payment of an early termination fee, after 12 years from the delivery of the leased premises to the Company. As of December 31, 2025, the Company’s extension and termination options under the 9804 Medical Center Drive Lease were excluded from the measurement of the right-of-use assets and lease liabilities as they were not reasonably certain of exercise. As required by the 9804 Medical Center Drive Lease, the Company has provided the landlord with an irrevocable letter of credit of $ 1.1 million which the landlord may draw upon in the event of any uncured default by the Company under the terms of the lease. Pursuant to the 9804 Medical Center Drive Lease, the Company received a $ 19.5 million tenant improvement allowance from the landlord to perform improvements to the leased premises. The tenant improvement allowance was recorded as a reduction of the right-of-use assets for the lease and is amortized on a straight-line basis as a reduction of lease expense over the term of the lease. The Company began occupation of a portion of the facility upon the completion of its construction in 2021. The remaining portion of the building, primarily associated with the manufacturing facility, was activated upon the completion of its construction in 2022. 112 Table of Contents As of December 31, 2025, the Company had recorded right-of-use assets of $ 40.8 million and lease liabilities of $ 65.6 million related to the 9804 Medical Center Drive Lease. 9712 Medical Center Drive In March 2015, the Company entered into an operating lease for office space at 9712 Medical Center Drive in Rockville, Maryland (the 9712 Medical Center Drive Lease). The lease term commenced in April 2015 , and monthly payments under the lease began in October 2015 and escalate annually in accordance with the lease agreement. The 9712 Medical Center Drive Lease has been amended from time to time to include additional office and laboratory space at an adjacent building located at 9714 Medical Center Drive and extend the term of the lease, which expires in February 2027, subject to extension options held by the Company. The Company has an option to extend the term of the lease for three additional years, as well as an option to extend the lease term to be coterminous with the 9804 Medical Center Drive Lease, which expires in September 2036 . As of December 31, 2025, the Company’s extension options under the 9712 Medical Center Drive Lease were excluded from the measurement of the right-of-use assets and lease liabilities as they were not reasonably certain of exercise. The Company received a $ 0.4 million tenant improvement allowance from the landlord which was recorded as a reduction of the right-of-use assets for the lease and is amortized on a straight-line basis as a reduction of lease expense over the term of the lease. As of December 31, 2025, the Company had recorded right-of-use assets of $ 1.8 million and lease liabilities of $ 2.0 million related to the 9712 Medical Center Drive Lease. New York Lease and Sublease In May 2016, the Company entered into an operating lease for office space in New York, New York (the New York Lease), which has since been amended to include additional office space and extend the term of the lease. The lease term commenced in July 2016 and expires in April 2027 . The Company received a $ 0.7 million tenant improvement allowance from the landlord which was recorded as a reduction of the right-of-use assets for the lease and is amortized on a straight-line basis as a reduction of lease expense over the term of the lease. As required by the New York Lease, the Company has provided the landlord with an irrevocable letter of credit of $ 0.2 million which the landlord may draw upon in the event of any uncured default by the Company under the terms of the lease. In March 2024, the Company entered into an agreement to sublease its office space under the New York Lease (the New York Sublease) to a third-party subtenant. The sublease term commenced in April 2024 and expires in April 2027 concurrent with the expiration of the New York Lease. Monthly payments under the New York Sublease commenced in July 2024 and escalate annually in accordance with the sublease agreement. As of December 31, 2025, total undiscounted future minimum lease payments to be received by the Company over the term of the New York Sublease were $ 0.7 million. During the years ended December 31, 2025 and 2024, the Company recognized sublease income of $ 0.5 million and $ 0.3 million, respectively, under the New York Sublease. The New York Sublease is classified as an operating lease and the Company was not relieved of its primary obligation under the New York Lease. The Company continues to account for the New York Lease as it did prior to the commencement of the sublease. As a result of the New York Sublease, the Company determined an impairment indicator was present as of March 31, 2024 related to the long-lived asset group subject to the sublease, which included the right-of-use asset under the New York Lease, leasehold improvements and other property and equipment allocable to the New York Sublease. The Company concluded the carrying value of the asset group as of March 31, 2024 was not recoverable, as it exceeded the sum of the estimated undiscounted cash flows to be generated by the assets over their remaining lives. The Company estimated the fair value of the asset group as of March 31, 2024 using a discounted cash flow method, which incorporated unobservable inputs including the net identifiable cash flows over the term of the New York Sublease and an estimated borrowing rate of a market participant subtenant. The estimated fair value of the asset group as of March 31, 2024 represents a Level 3 nonrecurring fair value measurement. The Company concluded the carrying value of the asset group of $ 3.4 million exceeded its estimated fair value of $ 1.3 million as of March 31, 2024. As such, the Company recognized impairment losses of $ 2.1 million during the year ended December 31, 2024 on the long-lived asset group associated with the New York Sublease. The impairment losses were allocated to the various assets within the long-lived asset group based on their relative carrying values and consisted of $ 1.4 million recorded to the right-of-use assets and $ 0.7 million recorded to property and equipment. No impairment losses on long-lived assets were recorded during the year ended December 31, 2025. As of December 31, 2025, the Company had recorded right-of-use assets of $ 0.3 million and lease liabilities of $ 1.4 million related to the New York Lease. 113 Table of Contents Other Leases In October 2022, the Company entered into an operating lease for office space in Washington, D.C. (the DC Lease). The lease term commenced in October 2022 and expires in October 2027 . The Company has an option to extend the term of the lease for five additional years. As of December 31, 2025, the Company’s extension option under the DC Lease was excluded from the measurement of the right-of-use assets and lease liabilities as it was not reasonably certain of exercise. As of December 31, 2025 the Company had recorded right-of-use assets of $ 2.7 million and lease liabilities of $ 2.8 million related to the DC Lease. The Company leases additional office, laboratory and warehousing facilities, as well as laboratory and other equipment, under operating leases with various expiration dates through 2029 , including leases which have been executed but have not yet commenced. Operating Lease Information All of the Company’s leases are classified as operating leases. The following table summarizes the Company’s lease costs and supplemental cash flow information related to its operating leases (in thousands): Years Ended December 31, 2025 2024 Operating lease cost $ 11,256 $ 11,168 Variable lease cost 3,064 2,725 Sublease income ( 451 ) ( 319 ) Total lease cost $ 13,869 $ 13,574 Cash paid for amounts included in operating lease liabilities $ 13,071 $ 12,969 Right-of-use assets acquired through operating lease liabilities $ 93 $ 826 Short-term lease expense for the years ended December 31, 2025 and 2024 was not material and is included in operating lease cost in the table above. Variable lease cost under the Company’s operating leases includes items such as common area maintenance, utilities, taxes and other charges. The following table presents the weighted-average remaining lease term and weighted-average discount rate of the Company’s operating leases: As of December 31, 2025 2024 Weighted-average remaining lease term (years) 9.8 10.3 Weighted-average discount rate 5.7 % 5.7 % The following table presents a reconciliation of the undiscounted future minimum lease payments remaining under the Company’s operating leases to the amounts reported as operating lease liabilities on the consolidated balance sheet as of December 31, 2025 (in thousands): As of December 31, 2025 Undiscounted future minimum lease payments: 2026 $ 12,237 2027 10,020 2028 7,943 2029 8,051 2030 8,134 Thereafter 50,855 Total undiscounted future minimum lease payments 97,240 Amount representing imputed interest ( 23,739 ) Total operating lease liabilities 73,501 Current portion of operating lease liabilities ( 8,286 ) Operating lease liabilities, non-current $ 65,215 The table above excludes future minimum lease payments for leases which were executed but had not yet commenced as of December 31, 2025, the total of which were not material. 114 Table of Contents 7. Royalty Monetization Liabilities Royalty monetization liabilities are accounted for as debt and consist of the following (in thousands): As of December 31, 2025 2024 2020 Royalty Purchase Agreement $ 29,672 $ 59,687 2025 Royalty Bond 157,345 — Total $ 187,017 $ 59,687 Current portion of royalty monetization liabilities $ 39,609 $ 34,309 Non-current portion of royalty monetization liabilities 147,408 25,378 Total $ 187,017 $ 59,687 2020 Royalty Purchase Agreement In December 2020, the Company entered into a royalty purchase agreement (the 2020 Royalty Purchase Agreement) with HCR. Under the 2020 Royalty Purchase Agreement, HCR purchased the Company’s rights to a capped amount of Zolgensma and Itvisma royalty payments under the Company’s license agreement with Novartis Gene Therapies (the Novartis License), including $ 4.0 million of royalty payments received by the Company in the fourth quarter of 2020. In consideration for these rights, HCR paid the Company $ 200.0 million (the Purchase Price), less $ 4.0 million representing the payment of the royalties received in the fourth quarter of 2020 to HCR. Beginning upon the effective date of the 2020 Royalty Purchase Agreement, Zolgensma and Itvisma royalty payments, up to a specified threshold, shall be paid to HCR, net of upstream royalties payable by the Company to certain licensors in accordance with existing license agreements. Pursuant to the 2020 Royalty Purchase Agreement, the total amount of Zolgensma and Itvisma royalty payments to be paid to HCR was subject to an increasing cap (the Cap Amount) equal to (i) $ 260.0 million applicable for the period from the effective date of the 2020 Royalty Purchase Agreement through November 7, 2024 (the First Cap Amount), and (ii) $ 300.0 million applicable for the period from November 8, 2024 through the effective date of termination of the Novartis License (the Second Cap Amount). If, on or prior to the defined dates for each Cap Amount, the total amount of royalties paid to HCR equals or exceeds the Cap Amount applicable to such date, the 2020 Royalty Purchase Agreement will automatically terminate. The First Cap Amount was not achieved prior to November 7, 2024, therefore the 2020 Royalty Purchase Agreement will remain in effect until the achievement of the Second Cap Amount or the termination of the Novartis License, if earlier. The Company has no obligation to repay any amounts to HCR under the 2020 Royalty Purchase Agreement if future Zolgensma and Itvisma royalty payments are not sufficient to achieve the applicable Cap Amount prior to the termination of the Novartis License. The Company has a call option to repurchase its rights to the royalties under the 2020 Royalty Purchase Agreement for a repurchase price equal to, as of the option exercise date, $ 300.0 million minus the total amount of royalty payments paid to HCR. The proceeds received from HCR under the 2020 Royalty Purchase Agreement of $ 196.0 million were recorded as a liability, net of transaction costs of $ 3.5 million, which is amortized over the estimated life of the arrangement using the effective interest method. In order to determine the amortization of the liability, the Company is required to estimate the total amount of future royalty payments to be paid to HCR, subject to the Cap Amount, over the life of the arrangement. The total amount of royalty payments paid to HCR, less the net proceeds received by the Company of $ 192.5 million, is recorded as interest expense over the life of the arrangement using the effective interest method. Due to its continuing involvement in the Novartis License, the Company continues to recognize royalty revenue on net sales of Zolgensma and Itvisma and records the royalty payments to HCR as a reduction of the liability when paid. As such payments are made to HCR, the balance of the liability will be effectively repaid over the life of the arrangement. The Company estimates the effective interest rate used to record interest expense under the 2020 Royalty Purchase Agreement based on its estimate of total Zolgensma and Itvisma royalties to be paid HCR under the arrangement. At each reporting date, the Company reassesses its estimate of total future royalty payments to be paid to HCR at the applicable Cap Amount, and prospectively adjusts the effective interest rate and amortization of the liability as necessary. Over the life of the arrangement, the actual effective interest rate will be affected by the amount and timing of royalty payments actually paid to HCR, which may differ from the Company’s forecasts. The estimated effective interest rate in effect as of December 31, 2025 and 2024 was 85.2 % and 65.5 %, respectively, which was based on the amortized balance of the liability and the estimated remaining royalties to be paid to HCR under the arrangement. The estimated interest rate is subject to adjustments in the future based on actual royalties paid to HCR and changes in the royalty forecast. As of December 31, 2025, the estimated effective interest rate over the life of the 2020 Royalty Purchase 115 Table of Contents Agreement, taking into account actual royalties paid to date and the estimated remaining royalties to be paid under the arrangement, was 16.3 %. The following table presents the changes in the royalty monetization liability under the 2020 Royalty Purchase Agreement with HCR (in thousands): 2020 Royalty Purchase Agreement Balance at December 31, 2023 $ 94,052 Novartis royalties paid to HCR ( 46,413 ) Interest expense recognized 12,048 Balance at December 31, 2024 59,687 Novartis royalties paid to HCR ( 60,095 ) Interest expense recognized 30,080 Balance at December 31, 2025 29,672 Current portion ( 29,672 ) Non-current portion $ — 2025 Royalty Bond In May 2025, the Company entered into a loan agreement with HCR pursuant to which HCR will provide the Company with an aggregate limited recourse loan of up to $ 250.0 million (the 2025 Royalty Bond). The 2025 Royalty Bond is disbursable to the Company in three tranches, with $ 150.0 million funded on the closing date in May 2025, $ 50.0 million available to be funded if sales of a specified product exceed a specified threshold prior to December 31, 2026, and $ 50.0 million available to be funded if both parties exercise an option in 2027. Loan proceeds under the 2025 Royalty Bond are funded to the Company net of an original issue discount of 2.25 % and reimbursement of certain expenses to HCR. Proceeds received by the Company from the initial funding tranche of the 2025 Royalty Bond in May 2025, net of discounts and transaction costs, were $ 144.5 million. Prior to the maturity date, interest and principal under the 2025 Royalty Bond shall be paid quarterly to HCR solely using proceeds received from certain specified royalties, milestone payments, license fees and other consideration payable to the Company under specified license agreements (collectively, the Royalty Interest), including (i) the Novartis License for Zolgensma and Itvisma, (ii) the collaboration and license agreement with Nippon Shinyaku for RGX-121 and RGX-111, and (iii) NAV Technology Platform license agreements with Rocket Pharmaceuticals, Inc. and Ultragenyx Pharmaceutical Inc. Zolgensma and Itvisma royalties earned under the Novartis License shall only be included in the Royalty Interest after full repayment of the applicable Cap Amount under the 2020 Royalty Purchase Agreement with HCR. The Royalty Interest excludes, and the Company retains the rights to, certain other consideration payable under the license agreements including certain milestone payments, license fees and reimbursement of costs as applicable. The Royalty Interest is payable to HCR net of upstream royalty and sublicense fee obligations payable by the Company to applicable licensors. The 2025 Royalty Bond is collateralized by a security interest and lien on the Royalty Interest. The 2025 Royalty Bond bears interest at a rate of 9.75 % plus the 3-month secured overnight financing rate as administered by the Federal Reserve Bank of New York ( SOFR ), with a minimum interest rate of 14.0 %. Interest payments are due quarterly using proceeds received under the Royalty Interest. At each payment date, any proceeds received under the Royalty Interest in excess of the interest payment due will be applied to outstanding principal. If the proceeds received under the Royalty Interest are insufficient to pay the interest due, unpaid interest will accrue to the principal balance. The 2025 Royalty Bond matures in May 2035 , subject to potential extension, unless repaid in full at an earlier date. The maturity date may be extended by two years to May 2037 subject to a potential patent term extension of a specific patent. Upon maturity, the outstanding principal and interest shall be due and payable to HCR. Additionally, upon repayment in full prior to the maturity date, or at the maturity date, the Company shall pay to HCR an additional amount equal to 5.0 % of the total outstanding principal as of the applicable determination date. Other than through the payment of proceeds received under the Royalty Interest, the 2025 Royalty Bond may not be prepaid prior to maturity. In connection with the loan agreement for the 2025 Royalty Bond, the Company also issued HCR warrants to purchase 268,096 shares of its common stock at an exercise price per share of $ 14.92 (the May 2025 Warrants). The May 2025 Warrants are exercisable upon issuance and expire 10 years from the closing date of the 2025 Royalty Bond. The Company evaluated the May 2025 Warrants and concluded the warrants are indexed to the Company's common stock and meet the criteria to be classified as equity. The net proceeds received by the Company under the loan agreement of $ 144.5 million were allocated between the 2025 Royalty Bond and 116 Table of Contents the May 2025 Warrants based on their relative fair values. The fair value of the 2025 Royalty Bond was determined based on the carrying amount of the loan on the closing date. The fair value of the May 2025 Warrants was determined using a Black-Scholes option-pricing model on the closing date, resulting in an estimated fair value of the warrants of $ 1.7 million. Based on the relative fair values of these instruments, $ 1.6 million of the net proceeds were allocated to the warrants and recorded as additional paid-in capital. The net proceeds allocated to the 2025 Royalty Bond were $ 142.9 million, resulting in a total debt discount of $ 7.1 million which is recorded as a reduction of the carrying value of the debt and will be amortized as interest expense over the life of the 2025 Royalty Bond. The effective interest rate of the 2025 Royalty Bond is partially estimated based on the Company's estimate of future payments under the Royalty Interest to be paid HCR. At each reporting date, the Company reassesses its estimate of total future payments to HCR under the arrangement and prospectively adjusts the effective interest rate and amortization of the debt and associated discount as necessary. Over the life of the arrangement, the actual effective interest rate will be affected by the amount and timing of the actual Royalty Interest payments to HCR and fluctuations in the variable interest rate, which may differ from the Company’s forecasts. The estimated effective interest rate in effect as of December 31, 2025 was 15.1 %, which was based on the amortized balance of the liability, the current coupon rate and the estimated remaining payments to HCR under the arrangement. The following table presents the changes in the royalty monetization liability under the 2025 Royalty Bond with HCR (in thousands): 2025 Royalty Bond Balance at December 31, 2024 $ — Proceeds from royalty bond, net of discount and issuance costs 142,883 Royalty interest paid to HCR ( 109 ) Portion of payments representing interest 109 Unpaid interest accrued to principal 13,449 Amortization of debt discount and issuance costs 1,013 Balance at December 31, 2025 157,345 Current portion ( 9,937 ) Non-current portion $ 147,408 8. Commitments and Contingencies In-licensed Technology The Company in-licenses intellectual property from third parties for technology and know-how used in its product candidates and development programs, some of which is further sublicensed to NAV Technology Licensees and collaboration partners. In-licenses may require the Company to make future payments relating to sublicense fees, milestone fees and royalties on future sales of licensed products. Additionally, the Company may be responsible for the cost of the maintenance of the intellectual property as incurred by its licensors. Up-front fees to obtain licensed technology, as well as associated milestone fees, are recorded as research and development expenses if the technology has no alternative future use. Sublicense fees are based on a specified percentage of license fees earned by the Company as a result of sublicensing the technology to third parties and are recorded as cost of revenues. Royalties due to licensors on sales of licensed products, including sales by NAV Technology Licensees, are recorded as cost of revenues. Patent maintenance costs are recorded as general and administrative expenses. Please refer to Note 10 for information on licenses granted by the Company and collaboration agreements with third parties. The Trustees of the University of Pennsylvania In February 2009, the Company entered into a license agreement, which has been amended from time to time (as amended, the Penn License), with The Trustees of the University of Pennsylvania (Penn) for exclusive, worldwide rights to certain patents owned by Penn underlying the Company’s NAV Technology Platform, as well as exclusive rights to certain data, results and other information. Pursuant to the originally agreed upon Penn License, the Company was obligated to pay Penn royalties on net sales of licensed products and sublicense fees. Additionally, the Company was obligated to reimburse Penn for certain costs incurred related to the maintenance of the licensed patents. 117 Table of Contents In April 2019, the Penn License was amended to include exclusive license rights to certain patent rights and know-how, including research data and other information, relating to the treatment of late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease. In consideration for the additional licensed rights, and in addition to any consideration owed under the license prior to the amendment, the Company paid Penn an up-front fee and is obligated to pay milestone fees of up to $ 20.5 million upon the achievement of various development and sales-based milestones and additional royalties on net sales of licensed products for the treatment of CLN2 disease. From the inception of the agreement through December 31, 2025, the Company had incurred $ 0.5 million for development milestones achieved, or deemed probable of achievement, under the Penn License. In March 2022, the Company and Penn entered into a letter agreement (the Penn Letter Agreement) pursuant to which the Company will pay to Penn a total of $ 20.0 million, consisting of (i) $ 8.0 million paid in April 2022 to satisfy payment of any sublicense fees due or owed in the future under the Penn License as a result of the Company’s collaboration and license agreement with AbbVie Global Enterprises Ltd., and (ii) $ 12.0 million to satisfy any other past or future obligations of the Company to pay sublicense fees under the Penn License, which is payable in four equal annual installments of $ 3.0 million beginning in March 2023. The Penn Letter Agreement amended the Penn License to remove the Company’s obligations to pay sublicense fees under the license agreement. The Company remains obligated to pay Penn royalties on net sales of licensed products, milestone fees and reimbursement of certain patent maintenance costs in accordance with the Penn License. The Company recognized a charge of $ 9.2 million as cost of revenues upon the execution of Penn Letter Agreement in March 2022, which consisted of $ 17.3 million representing the present value of the $ 20.0 million payable under the Penn Letter Agreement, less $ 8.1 million in sublicense fees previously recognized as expense by the Company in prior periods and accrued as liabilities prior to the effectiveness of the Penn Letter Agreement. The present value discount is accreted as interest expense over the contractual payment period using the effective interest method. Expenses incurred by the Company related to the Penn License were recorded as follows (in thousands): Years Ended December 31, 2025 2024 General and administrative $ 461 $ 299 Interest expense 356 612 $ 817 $ 911 As of December 31, 2025, the Company had recorded $ 3.0 million payable under the Penn License, net of present value discount, which was included in accounts payable and accrued expenses and other current liabilities on the consolidated balance sheet. As of December 31, 2024, the Company had recorded $ 5.8 million payable under the Penn License, net of present value discount, of which $ 2.9 million was included in accrued expenses and other current liabilities, and $ 2.9 million was included in other liabilities on the consolidated balance sheet. GlaxoSmithKline In March 2009, the Company entered into a license agreement, which was amended in April 2009 (as amended, the GSK License), with GlaxoSmithKline LLC (GSK) for exclusive, worldwide rights to certain patents underlying the Company’s NAV Technology Platform which are owned by Penn and exclusively licensed to GSK. Pursuant to the GSK License, the Company is obligated to pay GSK royalties on net sales of licensed products and sublicense fees. Additionally, the Company is obligated to reimburse GSK for certain costs incurred related to the maintenance of the licensed patents. The Company was also obligated to pay $ 1.5 million to GSK upon the achievement of various milestones, all of which have been achieved and paid. In connection with the execution of the Penn Letter Agreement in March 2022, the Company’s royalty obligations under the GSK License were assigned by GSK to Penn. Beginning upon the effective date of the Penn Letter Agreement in March 2022, any royalties payable by the Company under the GSK License shall be paid to Penn rather than GSK. The Company remains obligated to pay GSK sublicense fees and reimbursement of certain patent maintenance costs in accordance with the GSK License. 118 Table of Contents Expenses incurred by the Company related to the GSK License were recorded as follows (in thousands): Years Ended December 31, 2025 2024 Cost of license and royalty revenues: Royalties on net sales of Zolgensma and Itvisma $ 19,193 $ 33,180 Other 399 337 Total cost of license and royalty revenues 19,592 33,517 General and administrative 196 369 $ 19,788 $ 33,886 As of December 31, 2025, the Company had recorded $ 5.7 million payable under the GSK License, of which $ 5.7 million was included in accrued expenses and other current liabilities, and less than $ 0.1 million was included in other liabilities on the consolidated balance sheet. As of December 31, 2024, the Company had recorded $ 6.3 million payable under the GSK License, of which $ 6.2 million was included in accrued expenses and other current liabilities, and $ 0.1 million was included in other liabilities on the consolidated balance sheet. The Company has been notified of a dispute with GSK over the amount of sublicense fees paid by the Company to GSK under the GSK License. GSK claims there has been a significant underpayment by the Company as they are entitled to a sublicense payment on all amounts received by the Company from sublicensees, including royalties, and not just amounts received for GSK's sublicensed patents. The Company disagrees with GSK's interpretation of the GSK License and engaged in non-binding mediation with GSK but the dispute has not yet been resolved. The Company does not believe that a loss is probable, and no reasonable range of loss is estimable, related to this matter. No liabilities related to this matter were recorded as of December 31, 2025 and 2024. Emory University In August 2018, the Company entered into a license agreement (the Emory License) with Emory University (Emory) for an exclusive license to Emory’s interest in certain patent rights, which are co-owned by Emory and the Company, to commercialize products covered by the licensed patent rights in any country or territory. Patent rights licensed under the Emory License include certain rights which have been sublicensed by the Company to Novartis and are applicable to Itvisma for the treatment of certain patients with SMA. Pursuant to the Emory License, the Company is obligated to reimburse Emory for patent prosecution and maintenance expenses and pay Emory annual maintenance fees under certain circumstances, royalties on net sales, sublicense fees and fees upon the achievement of various milestones for the first licensed product. During the years ended December 31, 2025 and 2024, the Company incurred $ 0.1 million and $ 0.1 million, respectively, under the Emory License for milestone payments and patent maintenance costs. Clearside Biomedical In August 2019, the Company entered into an option and license agreement with Clearside Biomedical, Inc. (Clearside) pursuant to which the Company was granted an option to exclusively license the worldwide rights to certain patents related to Clearside’s proprietary, in-office SCS Microinjector ® for the delivery of ABBV-RGX-314 to the suprachoroidal space to treat wet AMD, DR and other diseases. The Company exercised its license option in October 2019, resulting in a payment of $ 1.6 million to Clearside payable under the license agreement. Additionally, the Company is obligated to pay milestone fees of up to $ 136.0 million upon the achievement of various development and sales-based milestones, as well as royalties on net sales of licensed products using the SCS Microinjector. Clearside is responsible for supplying the SCS Microinjector to the Company to support all preclinical, clinical and commercial needs. From the inception of the agreement through December 31, 2025, the Company had incurred $ 3.0 million for development milestones achieved, or deemed probable of achievement, under the agreement. In November 2025, Clearside announced that it filed a voluntary petition under Chapter 11 of the U.S. Bankruptcy Code in the District of Delaware and that it was seeking authorization to sell all or substantially all of its assets in a court-supervised auction and sale process under Section 363 of the U.S. Bankruptcy Code. Clearside subsequently announced that it entered into an asset purchase agreement with a stalking horse bidder, Health Ocean Pharma (Eye) Limited, for the sale of substantially all of its assets, including its remaining rights with respect to the SCS Microinjector. The sale process is still ongoing and is subject to pending objections by parties in interest, and, therefore, the ultimate outcome of that process is unknown. 119 Table of Contents Other Licenses In November 2014, the Company entered into a license agreement, which has been amended from time to time, with Regents of the University of Minnesota (Minnesota), for an exclusive license to Minnesota’s interest in certain patent rights which are co-owned by Minnesota and the Company to commercialize products covered by the licensed patent rights in any country or territory in which a licensed patent has been issued and is unexpired, or a licensed patent application is pending. Pursuant to the license agreement, the Company is obligated to pay Minnesota annual maintenance fees, royalties on net sales, sublicense fees and fees upon the achievement of various milestones. Additionally, the Company is obligated to pay for certain costs incurred related to the maintenance of the licensed patents. In June 2022, the Company entered into a license agreement with Johns Hopkins University (JHU) for an exclusive license to JHU's interest in certain patent rights which are co-owned by JHU and the Company to commercialize products covered by the licensed patent rights in any country or territory. Pursuant to the license agreement, the Company paid JHU an upfront fee and is obligated to pay JHU royalties on net sales, minimum annual royalties, sublicense fees and fees upon the achievement of various milestones for the first two licensed products. Additionally, the Company is obligated to pay for certain costs incurred related to the maintenance of the licensed patents. Other Funding Commitments In the normal course of business, the Company enters into agreements with contract research organizations, contract manufacturing organizations and other third parties for services to be provided to the Company. Generally, these agreements provide for termination upon notice, with specified amounts due upon termination based on the timing of termination and the terms of the agreement. The actual amounts and timing of payments under these agreements are uncertain and contingent upon the initiation and completion of services to be provided to the Company. Guarantees and Indemnifications In the normal course of business, the Company enters into agreements that contain a variety of representations and provide for general indemnification. The Company’s potential exposure under these agreements is unknown because it involves claims that may be made against the Company in the future. To date, the Company has no t paid any claims or been required to defend any action related to its indemnification obligations. As of December 31, 2025 and 2024 , the Company did no t have any material indemnification claims that were probable or reasonably possible and consequently had not recorded any related liabilities. Litigation On or about February 13, 2026, a putative securities class action complaint was filed by Andre Kuik against the Company and certain of its current officers and directors in the United States District Court for the District of Maryland. The complaint asserts claims under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, on behalf of a putative class of persons who purchased or otherwise acquired the Company's securities during the period from February 9, 2022 through January 27, 2026. The complaint alleges that the Company misled investors concerning the viability and safety of RGX-111 study, and that the Company's stock price declined following the announcement of the clinical holds imposed by the FDA on the Company’s RGX-111 and RGX-121 programs on January 28, 2026. The plaintiff seeks unspecified compensatory damages, attorneys' fees, expert fees and other costs, and other relief as the court may deem just and proper. The Company believes that it has meritorious defenses to the claims asserted and intends to vigorously defend against them. The Company does not believe that a loss is probable, and no reasonable range of loss is estimable, related to this matter. No liabilities related to this matter were recorded as of December 31, 2025. 9. Capitalization As of December 31, 2025 and 2024 , the authorized capital stock of the Company included 100,000,000 shares of common stock, par value $ 0.0001 per share, and 10,000,000 shares of preferred stock, par value $ 0.0001 per share. The Company’s restated certificate of incorporation and bylaws contain the rights, preferences and privileges of the Company’s stockholders and their respective shares. 120 Table of Contents Shares of common stock reserved for future issuance were as follows (in thousands): As of December 31, 2025 2024 Reserved for issuance under equity incentive plans 20,133 13,548 Reserved for issuance under employee stock purchase plan 755 913 Reserved for exercise of warrants outstanding 1,138 1,325 22,026 15,786 May 2025 Warrants In May 2025, in connection with issuance of the 2025 Royalty Bond, the Company issued to HCR the May 2025 Warrants to purchase 268,096 shares of its common stock at an exercise price per share of $ 14.92 . The May 2025 Warrants are exercisable upon issuance and have a contractual term of 10 years. The Company evaluated the May 2025 Warrants and concluded the warrants are indexed to the Company's common stock, meet the criteria to be classified as equity and are not subject to remeasurement. The Company allocated $ 1.6 million of the net proceeds from the 2025 Royalty Bond to the issuance of the May 2025 Warrants, which were recorded as additional paid-in capital. Please refer to Note 7 for further information on the May 2025 Warrants issued in connection with the 2025 Royalty Bond. As of December 31, 2025, no ne of the May 2025 Warrants had been exercised and 268,096 of the May 2025 Warrants remained outstanding. March 2024 Public Offering and Pre-funded Warrants In March 2024, the Company completed a public offering of 4,565,260 shares of its common stock at a price of $ 23.00 per share and 1,521,740 pre-funded warrants (the March 2024 Pre-funded Warrants) to purchase shares of its common stock at a price of $ 22.9999 per pre-funded warrant, which equaled the public offering price per share of the common stock less the $ 0.0001 exercise price of each pre-funded warrant. The aggregate net proceeds received by the Company from the offering were $ 131.1 million, net of underwriting discounts and commissions and offering expenses. The rights and privileges of the March 2024 Pre-funded Warrants are set forth in the warrant agreement between the Company and each of the respective warrant holders. The March 2024 Pre-funded Warrants are exercisable at the option of the warrant holder at any time and do not expire. However, as set forth in the warrant agreements with each holder, the number of pre-funded warrants that may be exercised at any given time may be limited if, upon exercise, the warrant holder and any of its affiliates would beneficially own more than 9.99 % of the Company’s common stock, or have voting power of more than 9.99 % of the Company's common stock. The limitation threshold may be increased or decreased by the warrant holder, with advance notice to the Company, to any other percentage not less than 4.99 % nor in excess of 19.99 %. The March 2024 Pre-funded Warrants do not provide any of the rights or privileges provided by the Company's common stock, including any voting rights, until the pre-funded warrants are exercised and settled in underlying shares of common stock. The Company evaluated the March 2024 Pre-funded Warrants and concluded the warrants are indexed to the Company's common stock, meet the criteria to be classified as equity and are not subject to remeasurement. The proceeds received from the issuance of the pre-funded warrants were recorded as additional paid-in capital. During the years ended December 31, 2025 and 2024, the Company issued 455,137 shares and 197,000 shares, respectively, of common stock upon the exercise of March 2024 Pre-funded Warrants. As of December 31, 2025, 869,603 of the March 2024 Pre-funded Warrants remained outstanding. At-the-Market Offering Programs In September 2023, the Company entered into an ATM Equity Offering SM Sales Agreement with BofA Securities, Inc. (BofA) pursuant to which the Company may offer and sell shares of its common stock having an aggregate offering price of up to $ 150.0 million from time to time through BofA, acting as the Company's sales agent (the BofA ATM Program). The Company terminated the BofA ATM Program effective in November 2024 . No shares of common stock were sold under the BofA ATM Program prior to its termination. In December 2024, the Company entered into a Sales Agreement with Leerink Partners LLC (Leerink) pursuant to which the Company may offer and sell shares of its common stock having an aggregate offering price of up to $ 150.0 million from time to time through Leerink, acting as the Company's sales agent (the Leerink ATM Program). As of December 31, 2025, no shares of common stock had been sold under the Leerink ATM Program. 121 Table of Contents 10. License and Collaboration Agreements License and Collaboration Revenues As of December 31, 2025 , the Company’s NAV Technology Platform was being applied by NAV Technology Licensees in two commercial products, Zolgensma and Itvisma, and in the development of various other licensed products. Additionally, the Company has licensed intellectual property rights to collaborators for the joint development and commercialization of certain product candidates. Consideration payable to the Company under its license and collaboration agreements may include: (i) up-front and annual fees, (ii) milestone payments based on the achievement of certain development and sales-based milestones, (iii) sublicense fees, (iv) royalties on sales of licensed products, (v) fees for services related to the development and manufacturing of licensed products and (vi) other consideration payable upon optional goods and services purchased by licensees and collaborators. Sublicense fees vary by license and range from a mid-single digit percentage to a low-double digit percentage of license fees received by licensees as a result of sublicenses. Royalties on net sales of commercialized products vary by license and range from a mid-single digit percentage to a low double-digit percentage of net sales by licensees. Revenues earned under license and collaboration agreements consisted of the following (in thousands): Years Ended December 31, 2025 2024 License and royalty revenue: Zolgensma and Itvisma royalties $ 83,177 $ 81,505 Nippon Shinyaku licenses 72,903 — Other 187 455 Total license and royalty revenue 156,267 81,960 Service revenue: Nippon Shinyaku services 11,822 — Other 2,352 1,368 Total service revenue 14,174 1,368 Total revenues $ 170,441 $ 83,328 Outstanding development milestone payments are evaluated each reporting period and are only included in the transaction price of each license to the extent the milestones are considered probable of achievement. Sales-based milestones are excluded from the transaction price of each license agreement and recognized as royalty revenue in the period of achievement. As of December 31, 2025, the Company’s license and collaboration agreements contained unachieved milestones which could result in aggregate milestone payments to the Company of up to $ 2.18 billion, including (i) $ 546.7 million upon the commencement of various stages of clinical trials, (ii) $ 106.3 million upon the submission of regulatory approval filings or upon regulatory approval of licensed products, and (iii) $ 1.53 billion upon the achievement of specified sales targets for licensed products, including milestones payable upon the first commercial sale of licensed products. To the extent the Company realizes the milestone payments, the Company may be obligated to pay sublicense fees to licensors based on a specified percentage of the fees earned by the Company. The achievement of these milestones is highly dependent on the successful development and commercialization of licensed products and it is at least reasonably possible that some or all of the milestone fees will not be realized by the Company. 122 Table of Contents Accounts Receivable, Contract Assets and Deferred Revenue The following table presents the balances of the Company’s accounts receivable, contract assets and deferred revenue, as well as other information regarding revenue recognized, during the periods presented (in thousands): Years Ended December 31, 2025 2024 Accounts receivable, net, current and non-current: Beginning of period $ 20,947 $ 25,491 End of period $ 28,691 $ 20,947 Contract assets: Beginning of period $ 239 $ — End of period $ 104 $ 239 Deferred revenue, current and non-current: Beginning of period $ 115 $ 148 End of period $ 29,395 $ 115 Revenue recognized during the period from: Amounts included in deferred revenue at beginning of period $ 115 $ 148 Performance obligations satisfied in previous periods $ 84,684 $ 81,585 Revenue recognized from performance obligations satisfied in previous periods, as presented in the table above, was primarily attributable to Zolgensma and Itvisma royalties and changes in the transaction prices of the Company’s license agreements. Changes in transaction prices were primarily attributable to development milestones achieved or deemed probable of achievement during the periods, resulting in a cumulative catch-up adjustment to revenue. Revenue recognized during the year ended December 31, 2025, included $ 1.5 million in cumulative catch-up adjustments for changes in the probability of achievement of development milestones. No cumulative catch-up adjustments for development milestones were recorded in revenue during the year ended December 31, 2024. As of December 31, 2025 , the Company had recorded deferred revenue of $ 29.4 million which represents consideration received or unconditionally due from licensees and collaboration partners for performance obligations that have not yet been satisfied by the Company. Unsatisfied performance obligations as of December 31, 2025 consisted of (i) development services to be performed related to licensed products, which will be satisfied as the services are performed, and (ii) material rights granted to purchase commercial supply of licensed products, which will be satisfied upon delivery of the commercial supply. As of December 31, 2025, the aggregate transaction price of the Company’s license and collaboration agreements allocated to performance obligations not yet satisfied or partially satisfied was $ 30.4 million, primarily associated with development services under the Company's collaboration and license agreement with Nippon Shinyaku, the substantial majority of which is expected to be satisfied over a period of approximately five years . Accounts receivable consisted of the following (in thousands): As of December 31, 2025 2024 Current accounts receivable: Billed to customers $ 557 $ 65 Unbilled Novartis royalties 23,806 20,106 Unbilled Nippon Shinyaku services 1,997 — Other unbilled 19 302 Current accounts receivable 26,379 20,473 Non-current accounts receivable: Unbilled Nippon Shinyaku services 1,858 — Other unbilled 454 474 Non-current accounts receivable 2,312 474 Total accounts receivable $ 28,691 $ 20,947 123 Table of Contents The following table presents the changes in the allowance for credit losses related to accounts receivable and contract assets for the years ended December 31, 2025 and 2024 (in thousands): Allowance for Credit Losses Accounts Receivable Contract Assets Balance at December 31, 2023 $ 4,587 $ — Provision for credit losses — — Changes in present value discount of receivables 413 — Credit recoveries ( 5,000 ) — Balance at December 31, 2024 — — Provision for credit losses — — Changes in present value discount of receivables — — Credit recoveries — — Balance at December 31, 2025 $ — $ — The Company’s allowance for credit losses during the year ended December 31, 2024 was related solely to accounts receivable from Abeona Therapeutics Inc. (Abeona). Please refer to the section below, "Settlement Agreement with Abeona Therapeutics," for further information regarding amounts due from Abeona and the associated allowance for credit losses. Zolgensma and Itvisma License with Novartis Gene Therapies In March 2014, the Company entered into an exclusive license agreement (as amended, the Novartis License) with Novartis Gene Therapies. Under the Novartis License, the Company granted Novartis Gene Therapies an exclusive, worldwide commercial license, with rights to sublicense, to the NAV Technology Platform, as well as other certain rights, for the treatment of SMA in humans by in vivo gene therapy. In consideration for the rights granted under the license, Novartis Gene Therapies paid the Company (i) an up-front fee of $ 2.0 million upon the execution of the agreement in 2014, (ii) license fees totaling $ 180.0 million upon the amendment of the agreement in January 2018 and the subsequent acquisition of AveXis, Inc. (now Novartis Gene Therapies) by Novartis in May 2018, (iii) total cumulative payments of $ 12.3 million upon the achievement of various development milestones, and (iv) a sales-based milestone payment of $ 80.0 million upon the achievement of $ 1.0 billion in cumulative net sales of Zolgensma in 2020. In addition to the consideration above, Novartis Gene Therapies is obligated to pay to the Company fixed annual fees, royalties on net sales of licensed products and a percentage of any sublicense fees received by Novartis Gene Therapies from sublicensees for the licensed intellectual property rights. Royalties are payable by Novartis Gene Therapies at a mid-single to low double-digit percentage of net sales of licensed products using the NAV AAV9 vector, and a low double-digit percentage of net sales of licensed products using a licensed vector other than NAV AAV9, and are subject to reduction in specified circumstances. All development and sales-based milestones under the Novartis License have been achieved and there are no further milestone payments payable to the Company under the license agreement. In 2019, Novartis Gene Therapies launched commercial sales of Zolgensma for the treatment of SMA in patients under the age of two years old. In the fourth quarter of 2025, Novartis Gene Therapies launched commercial sales of Itvisma for the treatment of SMA in patients two years and older. Zolgensma and Itvisma are licensed products under the Novartis License, pursuant to which the Company receives royalties on net sales of the licensed products. The Company recognized the following amounts under the Novartis License (in thousands): Years Ended December 31, 2025 2024 Zolgensma royalties $ 82,536 $ 81,505 Itvisma royalties 641 — Other license revenue — 28 Total license and royalty revenue $ 83,177 $ 81,533 Interest income from licensing $ 41 $ 123 124 Table of Contents As of December 31, 2025 and 2024 , the Company had recorded total accounts receivable of $ 24.1 million and $ 20.4 million, respectively, from Novartis Gene Therapies under the Novartis License, which consisted primarily of Zolgensma and Itvisma royalties receivable. Royalties receivable from Novartis recorded as of December 31, 2025 included $ 18.3 million expected to be paid to HCR in accordance with the 2020 Royalty Purchase Agreement discussed in Note 7. Settlement Agreement with Abeona Therapeutics In November 2021, the Company entered into a settlement agreement and mutual release with Abeona (the Settlement Agreement) related to claims associated with a license agreement between the parties which was terminated in May 2020. The Settlement Agreement resolved all arbitration and legal proceedings and mutually released each party from any and all claims under the terminated license agreement. Pursuant to the Settlement Agreement, Abeona paid the Company a total of $ 30.0 million as follows: (i) $ 20.0 million paid in November 2021, (ii) $ 5.0 million paid in November 2022, and (iii) $ 5.0 million paid in November 2024. As of December 31, 2025 and 2024, all amounts due from Abeona under the Settlement Agreement had been paid in full and no further amounts were due to the Company from Abeona. As of December 31, 2023, the Company had recorded accounts receivable of $ 4.6 million associated with the remaining amounts due from Abeona under the Settlement Agreement, which consisted of the $ 5.0 million payment due by November 2024, net of discount to present value. Based on the Company's evaluation of Abeona's credit profile and financial condition, and its expectations regarding Abeona's future cash flows and ability to satisfy the contractual obligations of the Settlement Agreement, the Company recorded an allowance for credit losses of $ 4.6 million as of December 31, 2023 related to the accounts receivable due from Abeona. Prior to collection, the present value discount of the Abeona receivable was accreted as interest income from licensing through the contractual due date using the effective interest method. The Company elected to record increases in the allowance for credit losses associated with the accretion of the present value discount as a reduction of the associated interest income, resulting in no interest income recognized related to the accretion of the present value discount. The Company collected the final payment of $ 5.0 million due from Abeona under the Settlement Agreement upon its contractual due date in November 2024. As a result of the full collection of the receivable, the Company recorded a credit recovery of $ 5.0 million during the year ended December 31, 2024 against the associated allowance for credit losses. Collaboration Agreements AbbVie Collaboration and License Agreement In September 2021, the Company entered into a collaboration and license agreement with AbbVie Global Enterprises Ltd. (AbbVie), a subsidiary of AbbVie Inc., to jointly develop and commercialize ABBV-RGX-314, the Company’s product candidate for the treatment of wet AMD, DR and other chronic retinal diseases (as amended, the AbbVie Collaboration Agreement). The AbbVie Collaboration Agreement became effective in November 2021. Pursuant to the AbbVie Collaboration Agreement, the Company granted AbbVie a co-exclusive license to develop and commercialize ABBV-RGX-314 in the United States and an exclusive license to develop and commercialize ABBV-RGX-314 outside the United States. The Company and AbbVie will collaborate to develop ABBV-RGX-314 in the United States, and AbbVie will be responsible for the development of ABBV-RGX-314 in specified markets outside the United States. Global development expenses for ABBV-RGX-314 are shared by the parties in accordance with the AbbVie Collaboration Agreement, with AbbVie being responsible for the majority of total development expenses. The Company will lead the manufacturing of ABBV-RGX-314 for clinical development and U.S. commercial supply, and AbbVie will lead the manufacturing of ABBV-RGX-314 for commercial supply outside the United States. Manufacturing expenses will be allocated between the parties in accordance with the terms of the AbbVie Collaboration Agreement and mutually agreed supply agreements. If requested by AbbVie, the Company will manufacture up to a specified portion of ABBV-RGX-314 commercial supply for sales outside the United States at a price specified in the agreement. AbbVie will lead the commercialization of ABBV-RGX-314 globally, and the Company will participate in U.S. commercialization efforts as provided under a commercialization plan determined in accordance with the agreement. The Company and AbbVie will share equally in the net profits and net losses associated with the commercialization of ABBV-RGX-314 in the United States. Outside the United States, AbbVie will be responsible, at its sole cost, for the commercialization of ABBV-RGX-314. 125 Table of Contents In consideration for the rights granted under the AbbVie Collaboration Agreement, AbbVie paid the Company an up-front fee of $ 370.0 million upon the effective date of the agreement in November 2021 and is required to pay to the Company up to $ 1.38 billion upon the achievement of specified development and sales-based milestones, of which $ 562.5 million are based on development milestones and $ 820.0 million are sales-based milestones. AbbVie is also required to pay to the Company tiered royalties on net sales of ABBV-RGX-314 outside the United States at percentages in the mid-teens to low twenties, subject to specified offsets and reductions. In August 2025, the Company and AbbVie entered into an amendment to the AbbVie Collaboration Agreement which modified the development plan and milestone payment structure for the ABBV-RGX-314 DR program. Under the amendment, the Company will conduct the first registration enabling trial for DR suprachoroidal (SCS) treatment as a combined Phase IIb/III trial (NAAVIGATE) which will be performed in two parts (Part 1 and Part 2), and AbbVie will conduct the second registration enabling trial as a separate, standalone Phase III trial. In lieu of a $ 200.0 million development milestone payable to the Company under the original AbbVie Collaboration Agreement upon first patient dosed in the first registration enabling trial for DR SCS treatment, AbbVie will pay the Company $ 100.0 million upon first patient dosed in the NAAVIGATE trial and an additional $ 100.0 million upon first patient dosed in the subsequent Phase III trial. Also pursuant to the amendment, AbbVie will lead a new Phase III randomized controlled study (ACHIEVE) to assess the injection burden, adverse events, change in disease activity, and long-term preservation of visual acuity of ABBV-RGX-314 in adult participants with neovascular AMD. The Company will be responsible for its development expenses to conduct Part 1 of the NAAVIGATE trial and the parties will share the development expenses related to Part 2 of the NAAVIGATE trial and the subsequent Phase III trial for DR in accordance with the existing terms of the AbbVie Collaboration Agreement. AbbVie will be responsible for all development expenses related to the ACHIEVE study. The AbbVie Collaboration Agreement contains provisions for termination, including termination for convenience by AbbVie. Contemporaneously with entering into the AbbVie Collaboration Agreement, the Company entered into a sublicense agreement with AbbVie (the AbbVie Sublicense Agreement) pursuant to which the Company granted AbbVie an exclusive sublicense to exploit licensed products in connection with the AbbVie Collaboration Agreement under specified patents licensed to the Company by Penn. The AbbVie Sublicense Agreement became effective contemporaneously with the AbbVie Collaboration Agreement in November 2021 and is coterminous with the AbbVie Collaboration Agreement. The Company evaluated its various commitments under the AbbVie Collaboration Agreement and identified the following distinct units of account: (i) delivery of an intellectual property license for the rights to develop and commercialize ABBV-RGX-314 globally, (ii) development, manufacturing and commercialization activities for ABBV-RGX-314 in the United States, and (iii) manufacturing of commercial supply for sales of ABBV-RGX-314 outside the United States, if requested by AbbVie. In determining the distinct units of account, the Company concluded that the license granted to AbbVie to develop and commercialize ABBV-RGX-314 is distinct from the other goods and services promised under the agreement, as AbbVie can benefit from the license on a standalone basis and, based on the stage of development of ABBV-RGX-314, the underlying licensed products and know-how are not expected to be significantly modified as a result of other goods and services promised under the agreement. For each of the distinct units of account identified under the AbbVie Collaboration Agreement, the Company determined whether the transactions should be accounted for as a contract with a customer within the scope of ASC 606 or as a collaborative arrangement within the scope of ASC 808. The Company concluded that the units of account for the delivery of the functional intellectual property license and the manufacturing of commercial supply for sales of ABBV-RGX-314 outside the United States should be accounted for as revenue under ASC 606, as AbbVie is deemed to be a customer for these transactions. The Company concluded that the unit of account for development, manufacturing and commercialization activities for ABBV-RGX-314 in the United States should be accounted for as a collaborative arrangement under ASC 808, as these represent joint operating activities for which the Company and AbbVie are both active participants and exposed to significant risks and rewards dependent on the commercial success of such activities. The Company applied the requirements of ASC 606 to the AbbVie Collaboration Agreement for the units of account in which AbbVie was deemed to be a customer. The Company determined that there is only one material performance obligation under the agreement for the delivery of the intellectual property license to develop and commercialize ABBV-RGX-314 globally. The intellectual property licensed to AbbVie includes the rights to certain patents, data, know-how and other rights developed and owned by the Company, as well as other intellectual property rights exclusively licensed by the Company from various third parties. The Company evaluated options granted to AbbVie under the agreement and determined that the options do not represent material rights, and therefore are not considered separate performance obligations under the current arrangement. Specifically, the Company concluded that the option granted to AbbVie to purchase commercial supply of ABBV-RGX-314 from the Company for a portion of sales outside the United States does not convey a material right, as the option is not priced at an incremental discount to the standalone selling price of the underlying goods and services. Additionally, the Company identified various promises under the AbbVie Collaboration Agreement which were determined to be immaterial in the context of the contract and will not be accounted for as separate performance obligations. 126 Table of Contents As of December 31, 2025 and 2024, the transaction price of the AbbVie Collaboration Agreement was $ 370.0 million, which consisted solely of the up-front payment received from AbbVie in November 2021. The $ 370.0 million transaction price was fully recognized as revenue upon the delivery of the license to AbbVie in November 2021. Variable consideration under the AbbVie Collaboration Agreement, which has been excluded from the transaction price, includes $ 562.5 million in payments for development milestones that have not yet been achieved and were not considered probable of achievement. Additionally, the transaction price excludes sales-based milestone payments of $ 820.0 million and royalties on net sales of ABBV-RGX-314 outside the United States. Development milestones will be added to the transaction price and recognized as revenue upon achievement, or if deemed probable of achievement. In accordance with the sale- or usage-based royalty exception under ASC 606, royalties on net sales and sales-based milestones will be recognized as revenue in the period the underlying sales occur or milestones are achieved. There were no changes in the transaction price of the AbbVie Collaboration Agreement, and no revenue was recognized, during the years ended December 31, 2025 and 2024. The Company applied the requirements of ASC 808 to the AbbVie Collaboration Agreement for the units of account which were deemed to be a collaborative arrangement. Both the Company and AbbVie will perform various activities related to the development, manufacturing and commercialization of ABBV-RGX-314 in the United States. Development costs are shared between the parties in accordance with the terms of the AbbVie Collaboration Agreement, and the parties will share equally in the net profits and losses derived from sales of ABBV-RGX-314 in the United States. The Company accounts for payments to and from AbbVie for the sharing of development and commercialization costs in accordance with its accounting policy for collaborative arrangements. Amounts owed to AbbVie for the Company’s share of development costs or commercialization costs incurred by AbbVie are recorded as research and development expense or general and administrative expense, respectively, in the period the costs are incurred. Amounts owed to the Company for AbbVie’s share of development costs or commercialization costs incurred by the Company are recorded as a reduction of research and development expense or general and administrative expense, respectively, in the period the costs are incurred. At the end of each reporting period, the Company records a net amount due to or from AbbVie as a result of the cost-sharing arrangement. As of December 31, 2025 and 2024, the Company had recorded $ 10.9 million and $ 11.3 million, respectively, due from AbbVie for net reimbursement of costs incurred for activities performed under AbbVie Collaboration Agreement, which was included in other current assets on the consolidated balance sheets. The Company recognized the following amounts under the AbbVie Collaboration Agreement (in thousands): Years Ended December 31, 2025 2024 Net cost reimbursement to (from) AbbVie included in: Research and development expense $ ( 60,222 ) $ ( 78,316 ) General and administrative expense 2,678 1,866 Total net cost reimbursement to (from) AbbVie $ ( 57,544 ) $ ( 76,450 ) Nippon Shinyaku Collaboration and License Agreement In January 2025, the Company entered into a collaboration and license agreement with Nippon Shinyaku for the development and commercialization of RGX-121, the Company’s product candidate for the treatment of MPS II, and RGX-111, the Company's product candidate for the treatment of MPS I (the Nippon Shinyaku Collaboration Agreement). The Nippon Shinyaku Collaboration Agreement became effective in March 2025. Pursuant to the Nippon Shinyaku Collaboration Agreement, the Company granted Nippon Shinyaku a license to develop and exclusively commercialize RGX-121 and RGX-111 in the United States and certain countries in Asia. The Company is responsible for the development of RGX-121 and RGX-111 in the United States, and Nippon Shinyaku is responsible for development in licensed territories outside the United States. The Company is responsible for the manufacturing of RGX-121 and RGX-111 for clinical development and commercial supply, and manufacturing expenses will be allocated between the parties in accordance with the terms of the Nippon Shinyaku Collaboration Agreement and mutually agreed supply agreements. Nippon Shinyaku will be responsible, at its sole cost, for the commercialization of RGX-121 and RGX-111 in the licensed territories. The Company reserves the right to develop and commercialize RGX-121 and RGX-111 in countries outside the licensed territories. The Nippon Shinyaku Collaboration Agreement contains provisions for termination, including termination for convenience by Nippon Shinyaku. In consideration for the rights granted and services to be performed under the Nippon Shinyaku Collaboration Agreement, Nippon Shinyaku paid the Company an up-front fee of $ 110.0 million upon the effective date of the agreement in March 2025 and is required to pay to the Company up to $ 700.0 million upon the achievement of specified development and sales-based milestones, of which $ 40.0 million are based on development milestones and $ 660.0 million are sales-based milestones. Nippon Shinyaku is also 127 Table of Contents required to pay to the Company double-digit royalties on net sales of RGX-121 and RGX-111 in the licensed territories, subject to specified offsets and reductions. The Company retains all rights to, and any proceeds related to the sale of, any priority review vouchers that may be issued upon the potential approvals of RGX-121 and RGX-111. The Company evaluated its various commitments under the Nippon Shinyaku Collaboration Agreement and identified the distinct units of account under the arrangement. For each of the distinct units of account identified, the Company determined whether the transactions should be accounted for as a contract with a customer within the scope of ASC 606 or as a collaborative arrangement within the scope of ASC 808. The Company concluded that each of the distinct units of account identified should be accounted for as revenue under ASC 606, as Nippon Shinyaku is deemed to be a customer for each of the various transactions. The Company identified the following material performance obligations under the agreement: (i) delivery of intellectual property licenses to develop and commercialize RGX-121 and RGX-111 in the United States and Asia territories, (ii) development services for RGX-121 and RGX-111 in the United States, including manufacturing of clinical supply and commercial supply prior to regulatory approval, and (iii) material rights granted to Nippon Shinyaku to purchase commercial supply for sales in licensed territories. The intellectual property licensed to Nippon Shinyaku includes the rights to certain patents, data, know-how and other rights developed and owned by the Company, as well as other intellectual property rights exclusively licensed by the Company from various third parties. In determining the distinct performance obligations under the agreements, the Company concluded that the licenses granted to Nippon Shinyaku to develop and commercialize RGX-121 and RGX-111 are distinct from the other goods and services promised under the agreement, as Nippon Shinyaku can benefit from the licenses on a standalone basis and, based on the stage of development of the product candidates, the underlying licensed products and know-how are not expected to be significantly modified as a result of other goods and services promised under the agreement. The Company evaluated all options granted to Nippon Shinyaku under the agreement to determine whether the options represent material rights. Management concluded the options to purchase commercial supply convey material rights granted to Nippon Shinyaku, and therefore are accounted for as separate performance obligations under the current arrangement. The Company identified various promises under the Nippon Shinyaku Collaboration Agreement which were determined to be immaterial in the context of the contract and will not be accounted for as separate performance obligations. As of December 31, 2025, the transaction price of the Nippon Shinyaku Collaboration Agreement included fixed consideration of $ 110.0 million for the up-front payment and variable consideration of $ 4.1 million for estimated reimbursable costs of manufacturing and other services which are deemed not to be constrained. Variable consideration which has been excluded from the transaction price includes $ 40.0 million in payments for development milestones that have not yet been achieved and were not considered probable of achievement, and reimbursable costs of manufacturing and other services which are contingent on events occurring that are outside the Company’s control and are deemed to be constrained. The transaction price also excludes sales-based milestone payments of $ 660.0 million and royalties on net sales of RGX-121 and RGX-111 in the United States and Asia territories. Development milestones will be added to the transaction price upon achievement, or if deemed probable of achievement, and other variable consideration for manufacturing and other services may be added to the transaction price in the future as uncertainties regarding payment of the consideration are resolved. In accordance with the sale- or usage-based royalty exception under ASC 606, royalties on net sales and sales-based milestones will be recognized as revenue in the period the underlying sales occur or milestones are achieved. There were no changes in the fixed transaction price of the Nippon Shinyaku Collaboration Agreement between the effective date of the agreement and December 31, 2025. The fixed transaction price of the Nippon Shinyaku Collaboration Agreement of $ 110.0 million was allocated to the various performance obligations based on their relative standalone selling prices, which requires significant judgment. The selling prices of the intellectual property licenses were determined based on discounted cash flow models for each of the licensed products in the respective licensed territories and were adjusted for the probability of developmental, regulatory and commercial success. Significant assumptions and judgments were required to estimate the future cash flows, including the addressable market, sales price per unit, discount rates and probabilities of success for each of the licensed products and territories. The selling prices of development services and commercial supply were determined based on the expected cost plus a reasonable margin. The selling prices of the material rights to purchase commercial supply were determined based on the incremental discount to the standalone selling prices of the commercial supply and were adjusted to consider the likelihood of exercise of the material rights. Significant assumptions and judgments were required to estimate the future costs of development and manufacturing, an appropriate margin for such services, and the likelihood of exercise of the material rights to purchase commercial supply. The $ 4.1 million of variable consideration included in the transaction price is allocated directly to performance obligations for the manufacturing of commercial supply prior to regulatory approval and other service obligations since the consideration is directly associated with the performance of such services and reimbursement of applicable costs. Consideration contingent upon the future exercise of options to purchase commercial supply is excluded from the transaction price until exercised. 128 Table of Contents The portion of the $ 110.0 million fixed transaction price allocated to the delivery of the intellectual property licenses was recognized as license and royalty revenue upon the delivery of the licenses to Nippon Shinyaku in March 2025. The portion of the fixed transaction price allocated to development services will be recognized as service revenue as the services are performed using an input method based on costs incurred versus total estimated costs to perform the services, which is re-assessed at each reporting date. The portion of the fixed transaction price allocated to material rights to purchase commercial supply will be recognized as revenue proportionally with the total expected commercial supply revenue expected to be recognized under the arrangement, which is re-assessed at each reporting date. Commercial supply revenue will be recognized as revenue upon delivery to Nippon Shinyaku, or otherwise upon transfer of control of commercial supply to Nippon Shinyaku as defined in the associated supply agreements. The Company recognized the following amounts under the Nippon Shinyaku Collaboration Agreement (in thousands): Years Ended December 31, 2025 2024 License and royalty revenue $ 72,903 $ — Service revenue 11,822 — Total revenues $ 84,725 $ — As of December 31, 2025, the Company had recorded total accounts receivable of $ 4.1 million for reimbursable costs of manufacturing and other services under the Nippon Shinyaku Collaboration Agreement, of which $ 2.3 million was included in current assets and $ 1.9 million was included in non-current assets. As of December 31, 2025, the Company had recorded total deferred revenue of $ 29.4 million for development services and material rights which have not yet been satisfied under the Nippon Shinyaku Collaboration Agreement, of which $ 10.5 million was included in current liabilities and $ 18.9 million was included in non-current liabilities. 11. Stock-based Compensation In September 2014, the Company adopted the 2014 Stock Plan (the 2014 Plan). In June 2015, the Company adopted the 2015 Equity Incentive Plan (the 2015 Plan), which replaced the 2014 Plan effective upon the Company’s initial public offering in September 2015. Upon the effective date of the 2015 Plan, no further awards may be granted under the 2014 Plan. As of December 31, 2025, there were no awards outstanding under the 2014 Plan. Effective in January 2025, an additional 1,981,975 shares were authorized for issuance under the 2015 Plan. The 2015 Plan expired in June 2025 , upon which no further awards may be granted under the plan. Any awards outstanding under the 2015 Plan as of the plan expiration date shall remain outstanding and effective pursuant to the contractual terms of the awards. In May 2025, the Company adopted the 2025 Equity Incentive Plan (the 2025 Plan), which replaced the 2015 Plan upon its expiration in June 2025. The total number of shares of common stock authorized for issuance under the 2025 Plan upon its adoption was 5,500,000 . The number of shares authorized for issuance under the 2025 Plan shall automatically increase for any shares of common stock underlying awards outstanding under the 2015 Plan, as of the adoption date of the 2025 Plan, which are not issued due to forfeiture, expiration, termination or cancellation of the award. Shares of common stock that are withheld, tendered, or otherwise not issued in connection with the settlement of awards outstanding under the 2015 Plan do not increase the number of shares authorized for issuance under the 2025 Plan. As of December 31, 2025, the total number of shares of common stock reserved for issuance under the 2025 Plan and 2015 Plan was 20,133,416 , of which 5,717,654 remained available for future grants under the 2025 Plan. The 2014 Plan, 2015 Plan and 2025 Plan provide for the issuance of stock options, stock appreciation rights, restricted and unrestricted stock and unit awards, and performance cash awards to employees, members of the Board of Directors and consultants of the Company. As of December 31, 2025, the Company has issued only stock options and restricted stock units under the plans. Stock options generally expire 10 years following the date of grant. Stock options typically vest over a four-year period, but vesting provisions can vary by award based on the discretion of the Board of Directors. Stock options have an exercise price at least equal to the estimated fair value of the Company’s common stock on the date of grant. Restricted stock units typically vest over a four-year period, but vesting provisions can vary by award based on the discretion of the Board of Directors. Upon vesting, restricted stock units are settled in common stock of the Company. Awards granted under the 2025 Plan generally have a minimum vesting requirement of one year from the grant date. 129 Table of Contents Shares of common stock underlying awards granted under the 2025 Plan which are not issued due to forfeiture, expiration, termination or cancellation of the award are added to the number of shares of common stock available for issuance under the 2025 Plan, except for shares that are withheld, tendered or otherwise not issued in connection with the settlement of the award. Shares available for issuance under the 2025 Plan and 2015 Plan may be either authorized but unissued shares of the Company’s common stock or common stock reacquired by the Company and held in treasury. The 2025 Plan expires in May 2035 , 10 years from its adoption date, unless earlier terminated. Stock-based Compensation Expense The Company’s stock-based compensation expense by award type was as follows (in thousands): Years Ended December 31, 2025 2024 Stock options $ 18,622 $ 23,518 Restricted stock units 15,278 14,455 Employee stock purchase plan 663 490 $ 34,563 $ 38,463 As of December 31, 2025, the Company had $ 47.7 million of unrecognized stock-based compensation expense related to stock options, restricted stock units and the 2015 Employee Stock Purchase Plan (the 2015 ESPP), which is expected to be recognized over a weighted-average period of 2.2 years. The Company recorded aggregate stock-based compensation expense in the consolidated statements of operations and comprehensive loss as follows (in thousands): Years Ended December 31, 2025 2024 Research and development $ 15,977 $ 17,985 General and administrative 18,586 20,478 $ 34,563 $ 38,463 Stock Options The following table summarizes stock option activity under the Company's equity incentive plans (in thousands, except per share data): Weighted- average Weighted- Remaining average Contractual Aggregate Exercise Life Intrinsic Shares Price (Years) Value (a) Outstanding at December 31, 2024 9,994 $ 29.48 5.9 $ 240 Granted 2,441 $ 8.02 Exercised ( 68 ) $ 4.70 Cancelled or forfeited ( 801 ) $ 27.12 Outstanding at December 31, 2025 11,566 $ 25.26 6.0 $ 17,523 Exercisable at December 31, 2025 7,953 $ 31.37 4.8 $ 2,495 Vested and expected to vest at December 31, 2025 11,566 $ 25.26 6.0 $ 17,523 (a) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair value of the common stock for the options that were in the money at the dates reported. 130 Table of Contents The weighted-average grant date fair value per share of options granted during the years ended December 31, 2025 and 2024 was $ 4.96 and $ 9.98 , respectively. During the years ended December 31, 2025 and 2024, the total number of stock options exercised was 67,735 and 290,753 , respectively, resulting in total proceeds of $ 0.3 million and $ 1.5 million, respectively. The total intrinsic value of options exercised during the years ended December 31, 2025 and 2024 was $ 0.3 million and $ 3.1 million, respectively. The fair values of options granted were estimated at each grant date using the Black-Scholes valuation model with the following weighted-average assumptions: Years Ended December 31, 2025 2024 Expected volatility 64 % 64 % Expected term (years) 6.0 6.0 Risk-free interest rate 4.3 % 4.0 % Expected dividend yield 0.0 % 0.0 % Restricted Stock Units The following table summarizes restricted stock unit activity under the Company's equity incentive plans (in thousands, except per share data): Weighted-average Grant Date Shares Fair Value Unvested balance at December 31, 2024 2,042 $ 19.95 Granted 1,724 $ 8.62 Vested ( 743 ) $ 21.27 Forfeited ( 173 ) $ 14.57 Unvested balance at December 31, 2025 2,850 $ 13.08 The total intrinsic value of restricted stock units vested during the years ended December 31, 2025 and 2024 was $ 6.0 million and $ 6.7 million, respectively. Employee Stock Purchase Plan In June 2015, the Board of Directors adopted the 2015 ESPP, which became effective upon the Company’s initial public offering in September 2015. The number of authorized shares reserved for issuance under the 2015 ESPP automatically increases on the first business day of each fiscal year by the lesser of (i) 1 % of the shares of common stock outstanding on the last business day of the prior fiscal year; or (ii) the number of shares determined by the Board of Directors. Unless otherwise determined by the administrator of the 2015 ESPP, two offering periods of six months’ duration will begin each year on January 1 and July 1. As of December 31, 2025, the total number of shares of common stock authorized for issuance under the 2015 ESPP was 1,426,994 , of which 755,306 remained available for future issuance. During the years ended December 31, 2025 and 2024 , 157,658 and 105,400 shares of common stock, respectively, were issued under the 2015 ESPP. 12. Retirement Plan The Company sponsors a defined-contribution retirement plan under Section 401(k) of the Internal Revenue Code (the 401(k) Plan). The 401(k) Plan covers all employees who meet defined minimum age and service requirements, and allows participants to defer a portion of their annual compensation. The Company matches employee deferrals up to a specified percentage of eligible compensation. For the years ended December 31, 2025 and 2024, the Company incurred expenses of $ 3.4 million and $ 3.1 million, respectively, for matching contributions to the 401(k) Plan. 131 Table of Contents 13. Income Taxes The components of loss before income taxes were as follows (in thousands): Years Ended December 31, 2025 2024 United States $ ( 193,795 ) $ ( 227,022 ) Foreign ( 83 ) ( 80 ) Total loss before income taxes $ ( 193,878 ) $ ( 227,102 ) Due to taxable losses and a full valuation allowance against its deferred tax assets, the Company did no t record a provision for income taxes in the U.S. (federal or state) or any foreign jurisdictions for the years ended December 31, 2025 and 2024. Net income taxes paid (net refunds received) were as follows (in thousands): Years Ended December 31, 2025 2024 Federal $ 280 $ — State: Maryland — ( 56 ) Illinois — ( 9 ) Other states 5 ( 7 ) Foreign — — Total net income taxes paid (net refunds received): $ 285 $ ( 72 ) Beginning in 2022, the Tax Cuts and Jobs Act of 2017 (the TCJA) eliminated the option to deduct research and development expenses currently and required taxpayers to amortize such costs over a period of five years for expenses incurred in the United States and a period of 15 years for expenses incurred outside the United States. This provision of the TCJA resulted in deferred tax assets of $ 122.1 million as of December 31, 2024 related to capitalized research and development expenses, net of amounts amortized to date. The One Big Beautiful Bill Act (OBBBA) was enacted in July 2025. The OBBBA amended U.S. federal tax laws by restoring the option for immediate expense recognition of research and development expenses incurred in the United States and making permanent the ability to claim 100% bonus depreciation on qualified property, among other changes. The Company currently expects to elect these options and deduct U.S. research and development expenses incurred in the current period, along with 100% bonus depreciation on eligible property placed in service, beginning in 2025. Research and development expenses incurred outside the United States will continue to be capitalized and amortized over a period of 15 years for tax purposes. Unamortized U.S. research and development expenses incurred prior to 2025 may be amortized over their remaining life, or over a period of one or two years beginning in 2025. The Company currently expects to amortize these amounts over two years beginning in 2025. The enactment of the OBBBA resulted in a decrease in deferred tax assets for capitalized research and development expenses and an increase in deferred tax assets for net operating loss (NOL) carryforwards during the year ended December 31, 2025. However, due to taxable losses and a full valuation allowance against its deferred tax assets, the enactment of the OBBBA had no material impact to the Company's income tax provision for the year ended December 31, 2025. The Company continues to evaluate the impact the OBBBA will have on its consolidated financial statements in future periods. The Organization for Economic Co-operation and Development (OECD) has introduced BEPS Pillar 2 rules that impose a global minimum tax rate of 15 %. Numerous countries enacted corresponding legislation that is effective at various dates beginning as early as January 1, 2024. These rules generally apply to multinational companies with consolidated revenue of at least € 750.0 million in at least two of the four preceding fiscal years. Based on the revenue thresholds established in the BEPS Pillar 2 rules, these changes do not have an impact on the Company’s income tax provision for the years ended December 31, 2025 and 2024. Further, under administrative guidance issued in January 2026, even if the Company were to exceed the applicable revenue threshold in future periods, it would be eligible to elect the Side-by-Side Safe Harbor, which is expected to mitigate the impact of the Pillar 2 rules on the Company’s income tax provision. 132 Table of Contents The following table presents a reconciliation of the U.S. federal statutory tax rate to the Company's effective tax rate for the years ended December 31, 2025 and 2024, presented in accordance with ASU 2023-09 (dollars in thousands): Year Ended December 31, 2025 Year Ended December 31, 2024 Amount Percent Amount Percent U.S. federal statutory tax rate $ ( 40,714 ) 21.0 % $ ( 47,692 ) 21.0 % State and local income tax benefit, net of federal tax effect — — % — — % Foreign tax effects: Ireland 17 0.0 % 17 0.0 % Effect of changes in tax laws or rates enacted in the current period — — % — — % Effects of cross-border tax laws — — % — — % Tax credits: Research and development and orphan drug tax credits ( 7,492 ) 3.9 % ( 9,582 ) 4.2 % Other tax credits ( 27 ) 0.0 % ( 35 ) 0.0 % Change in valuation allowance 40,418 ( 20.8 )% 51,658 ( 22.7 )% Nontaxable or nondeductible items: Stock-based compensation 5,385 ( 2.8 )% 3,171 ( 1.4 )% Executive compensation 1,440 ( 0.7 )% 2,633 ( 1.2 )% Other 1,137 ( 0.7 )% 3 0.0 % Changes in unrecognized tax benefits ( 148 ) 0.1 % — — % Other adjustments ( 16 ) 0.0 % ( 173 ) 0.1 % Effective tax rate $ — — % $ — — % The significant components of the Company’s net deferred tax assets were as follows (in thousands): As of December 31, 2025 2024 Deferred tax assets: Net operating loss carryforwards $ 184,528 $ 105,468 Research and development tax credits 94,867 87,030 Stock-based compensation 21,250 22,687 Lease liabilities 19,372 22,278 Liability related sale of future royalties 2,951 12,148 Capitalized research and development costs 77,147 122,082 Accruals and other 7,317 5,366 Total deferred tax assets before valuation allowance 407,432 377,059 Valuation allowance ( 374,413 ) ( 338,352 ) Total deferred tax assets 33,019 38,707 Deferred tax liabilities: Right-of-use assets ( 12,193 ) ( 14,293 ) Depreciation and amortization ( 20,826 ) ( 24,414 ) Total deferred tax liabilities ( 33,019 ) ( 38,707 ) Net deferred tax assets $ — $ — The Company evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets as of December 31, 2025 and 2024. Based on the Company’s history of operating losses, and other relevant facts and circumstances, the Company concluded that it was more likely than not that the benefit of its deferred tax assets will not be realized. Accordingly, the Company provided a full valuation allowance for its deferred tax assets as of December 31, 2025 and 2024. The valuation allowance increased by $ 36.1 million and $ 57.9 million during the years ended December 31, 2025 and 2024, respectively. The increase in the valuation allowance during the year ended December 31, 2025 was due primarily to federal and state NOLs and research and development tax credits generated during the period, partially offset by a decrease in capitalized research and development expenses as a result of the enactment of the OBBBA. The increase in the valuation allowance during the year ended December 31, 2024 was 133 Table of Contents due primarily to an increase in capitalized research and development expenses, and federal and state NOLs and research and development tax credits generated during the period. The following table presents the Company's U.S. federal and state NOL and tax credit carryforwards which may be available to offset future income tax liabilities (in thousands): As of December 31, 2025 Expiration Date (if not utilized) U.S. federal NOL carryforwards $ 754,390 Indefinite U.S. federal tax credit carryforwards $ 94,143 Various dates between 2037 and 2045 U.S. state NOL carryforwards $ 6,857 Indefinite U.S. state NOL carryforwards $ 388,008 Various dates between 2029 and 2045 U.S. state tax credit carryforwards $ 1,000 Various dates between 2029 and 2032 As of December 31, 2025 , the Company had U.S. federal and state research and development tax credit carryforwards of approximately $ 95.1 million which may be available to reduce future income tax liabilities. The calculation of these credits requires assumptions to be made by the Company to estimate qualified research expenses. The Company conducts formal studies to document the qualified activities and expenses used to calculate these credits however a portion of these credits may be subject to future examinations which have not yet occurred, the results of which may result in an adjustment to the Company’s credit carryforwards. The Company accounts for uncertain tax positions in accordance with the requirements of ASC 740, and recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. Further, a full valuation allowance has been provided against the net credit carryforwards and, if an adjustment is required upon the completion of the study, this adjustment would be offset by an adjustment to the deferred tax asset established for the research and development credit carryforwards and the valuation allowance. As of December 31, 2024 , the Company had total unrecognized tax benefits of $ 0.1 million which were reserved against its research and development tax credit carryforwards as uncertain tax positions. The Company released all of its reserves for unrecognized tax benefits during the year ended December 31, 2025 due to the expiration of the associated statute of limitations, and had no unrecognized tax benefits as of December 31, 2025. Under the provisions of the Internal Revenue Code, the Company’s NOL and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities. NOL and tax credit carryforwards may be subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders over a three-year period in excess of 50 %, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has completed several financings since its inception which may have resulted in a change in control as defined by Sections 382 and 383 of the Internal Revenue Code, or could result in a change in control in the future. The Company and its subsidiaries file income tax returns in the United States, at the federal level and in various states, and in foreign jurisdictions. The U.S. federal and state income tax returns are generally subject to tax examinations for the tax years ended December 31, 2021 onward. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state tax authorities to the extent utilized in a future period. 14. Restructuring In November 2023, the Company implemented a strategic pipeline prioritization and corporate restructuring designed to reduce operating expenses and prioritize the development of ABBV-RGX-314, RGX-202 and RGX-121. The restructuring included a reduction in workforce and other planned operating expenses, primarily in rare neurodegenerative disease development, early research and other general and administrative areas. In connection with the restructuring, the Company implemented a reduction in workforce of approximately 15 %, which was substantially completed in the fourth quarter of 2023. The Company recorded restructuring costs of $ 3.7 million during the year ended December 31, 2023, which primarily consisted of employee severance, continuing healthcare benefits and other employee-related costs. Restructuring costs associated with one-time termination benefits were recorded pursuant to ASC 420, while restructuring costs associated with ongoing benefit arrangements were recorded pursuant to ASC 712. During the year ended December 31, 2024, the Company recorded reductions in the restructuring liability of $ 0.4 million associated with changes in total estimated restructuring costs. As of December 31, 2024, all of the restructuring costs had been paid by the Company and no restructuring liability was recorded. No restructuring costs were recorded during the years ended December 31, 2025 and 2024. 134 Table of Contents The following table presents the changes in the Company's restructuring liability (in thousands): Restructuring Liability Balance at December 31, 2023 $ 1,806 Restructuring charges — Cash payments ( 1,370 ) Other adjustments ( 436 ) Balance at December 31, 2024 — Restructuring charges — Cash payments — Balance at December 31, 2025 $ — 15. Net Loss Per Share Since the Company incurred net losses for the years ended December 31, 2025 and 2024, common stock equivalents were excluded from the calculation of diluted net loss per share for such periods as their effect would be anti-dilutive. Accordingly, basic and diluted net loss per share were the same for such periods. The weighted-average number of common shares outstanding used in the basic and diluted net loss per share calculations includes the weighted-average effect of pre-funded warrants to purchase shares of the Company's common stock, as the pre-funded warrants are exercisable at any time for nominal cash consideration. The following potentially dilutive common stock equivalents outstanding at the end of the period were excluded from the computations of weighted-average diluted common shares for the periods indicated as their effects would be anti-dilutive (in thousands): Years Ended December 31, 2025 2024 Stock options issued and outstanding 11,566 9,994 Unvested restricted stock units outstanding 2,850 2,042 Employee stock purchase plan 93 47 May 2025 Warrants outstanding 268 — 14,777 12,083 16. Segment and Geographical Information Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker (CODM), or decision-making group, in making decisions on how to allocate resources and assess performance. The Company’s CODM , its Chief Executive Officer, views the Company’s operations and manages the business as one operating segment focused on the development and commercialization of gene therapies to treat an array of diseases. The determination of a single operating segment is consistent with the consolidated financial information regularly provided to the CODM. The CODM reviews and evaluates consolidated net income (loss) for purposes of assessing performance, making operating decisions and allocating resources. The CODM uses net income (loss) to assess performance versus operating budgets and in the preparation of near-term and long-range operating plans to inform decisions on resource and capital allocation. The CODM reviews consolidated cash, cash equivalents and marketable securities as a measure of segment assets. As of December 31, 2025 and 2024, the Company’s cash, cash equivalents and marketable securities were $ 240.9 million and $ 244.9 million, respectively. 135 Table of Contents The following table presents information about the Company's segment revenues, significant segment expenses regularly provided to the CODM, other segment items and consolidated net income (loss) (in thousands): Years Ended December 31, 2025 2024 Revenues $ 170,441 $ 83,328 Less: Cost of license and royalty revenues 20,298 33,567 Research and development expense Personnel 73,508 65,950 Direct development and support (a) 112,887 97,951 Facilities 11,276 11,410 Stock-based compensation 15,977 17,985 Depreciation and amortization 14,651 15,226 Total research and development expense 228,299 208,522 General and administrative expense Personnel 22,793 20,816 Other general and administrative (b) 35,018 29,480 Facilities 5,502 4,856 Stock-based compensation 18,586 20,478 Depreciation and amortization 964 989 Total general and administrative expense 82,863 76,619 Other segment items (c) ( 32,859 ) 8,278 Net loss $ ( 193,878 ) $ ( 227,102 ) (a) Direct development and support includes external goods and services for the development of product candidates and early-stage research activities, laboratory costs, consulting, development cost reimbursement to and from collaborators and other expenses in support of research and development activities. (b) Other general and administrative expenses include professional and administrative services, consulting, commercial cost reimbursement to and from collaborators and other corporate overhead expenses. (c) Other segment items include credit losses (recoveries), impairment of long-lived assets, other operating expenses, interest income from licensing, investment income and interest expense. The Company’s interest income during the years ended December 31, 2025 and 2024 included interest income from licensing as presented in the consolidated statements of operations and comprehensive loss, as well as interest income from investments of $ 12.2 million and $ 12.1 million, respectively, which is included within investment income in the consolidated statements of operations and comprehensive loss. For the year ended December 31, 2025 , 44 % and 25 % of the Company’s revenues were attributed to Japan and the United States, respectively, and no other countries accounted for 10 % or more of the Company’s revenues. For the year ended December 31, 2024 , 36 %, 10 % and 10 % of the Company’s revenues were attributed to the United States, Germany and United Arab Emirates, respectively, and no other countries accounted for 10 % or more of the Company’s revenues. The country of origin for license revenue is determined based on the country of domicile of the licensee. The country of origin for royalty revenue is determined based on the location of the underlying net sales of licensed products. The country of origin for service revenue is determined based on the location where the Company principally performs the services. The substantial majority of the Company’s assets reside in the United States. 136 Table of Contents 17. Supplemental Disclosures Other Current Assets Other current assets consisted of the following (in thousands): As of December 31, 2025 2024 Net cost reimbursement due from AbbVie $ 10,871 $ 11,304 Accrued interest on investments 1,004 1,094 Other 1,030 1,376 $ 12,905 $ 13,774 Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): As of December 31, 2025 2024 Accrued personnel costs $ 17,418 $ 17,607 Accrued external research and development expenses 10,229 8,998 Accrued sublicense fees and royalties 8,652 8,658 Accrued external general and administrative expenses 1,301 2,002 Accrued purchases of property and equipment 33 156 Other 757 649 $ 38,390 $ 38,070 137 Table of Contents EXHIBIT INDEX Incorporated by Reference Exhibit Number Description Form Exhibit Number Filing Date Filed or Furnished Herewith 1.1 Sales Agreement dated December 9, 2024 between the Registrant and Leerink Partners LLC 8-K 1.1 12/9/24 3.1 Restated Certificate of Incorporation 8-K 3.1 6/7/21 3.2 Amended and Restated Bylaws X 4.1 Specimen stock certificate evidencing the shares of common stock S-1 4.1 8/17/15 4.2 Description of Securities 10-K 4.2 3/13/25 4.3 Form of Pre-funded Warrant 8-K 4.1 3/11/24 4.4 REGENXBIO Inc. Warrant to Purchase Common Stock S-3 4.5 6/13/25 10.1 Form of Indemnity Agreement for directors and officers S-1 10.1 8/17/15 10.2* 2015 Equity Incentive Plan S-1/A 10.3 9/15/15 10.3* Form of Restricted Stock Unit Award Agreement for the 2015 Equity Incentive Plan 10-K 10.4 3/1/21 10.4* Form of Stock Option Award Agreement for the 2015 Equity Incentive Plan 10-K 10.5 3/1/21 10.5* REGENXBIO Inc. 2025 Equity Incentive Plan S-8 99.1 6/13/25 10.6* Form of Restricted Stock Unit Award Agreement for the 2025 Equity Incentive Plan 10-Q 10.2 8/7/25 10.7* Form of Stock Option Award Agreement for the 2025 Equity Incentive Plan 10-Q 10.3 8/7/25 10.8* 2015 Employee Stock Purchase Plan S-1/A 10.4 9/8/15 10.9* Employment Agreement effective as of July 1, 2024 between the Registrant and Curran Simpson 10-Q 10.1 8/1/24 10.10* Form of Employment Agreement for Executive Vice Presidents 10-K 10.9 2/27/24 10.11* Compensation Program for Non-Employee Directors 10-Q 10.1 8/3/22 10.12* Management Cash Incentive Plan S-1 10.29 8/17/15 10.13† License Agreement effective February 24, 2009 between the Registrant and The Trustees of the University of Pennsylvania S-1/A 10.9 9/15/15 10.14† First Amendment to License Agreement dated March 6, 2009 between the Registrant and The Trustees of the University of Pennsylvania S-1 10.10 8/17/15 10.15† Second Amendment to License Agreement effective September 9, 2014 between the Registrant and The Trustees of the University of Pennsylvania S-1/A 10.11 9/15/15 10.16† Third Amendment to License Agreement effective April 29, 2016 between the Registrant and The Trustees of the University of Pennsylvania 10-Q/A 10.36 12/23/16 10.17† Fourth Amendment to License Agreement effective April 4, 2019 between the Registrant and The Trustees of the University of Pennsylvania 10-Q 10.2 5/7/19 138 Table of Contents Incorporated by Reference Exhibit Number Description Form Exhibit Number Filing Date Filed or Furnished Herewith 10.18† Fifth Amendment to License Agreement effective September 11, 2020 between the Registrant and The Trustees of the University of Pennsylvania 10-Q 10.2 11/4/20 10.19† Letter Agreement dated March 21, 2022 between the Company and the Trustees of the University of Pennsylvania 10-Q 10.1 5/4/22 10.20† License Agreement dated March 6, 2009 between the Registrant and SmithKline Beecham Corporation d/b/a GlaxoSmithKline S-1/A 10.12 9/15/15 10.21 Amendment to License Agreement dated April 15, 2009 between the Registrant and SmithKline Beecham Corporation d/b/a GlaxoSmithKline S-1 10.13 8/17/15 10.22† License Agreement dated March 21, 2014 between the Registrant and AveXis, Inc. S-1/A 10.16 9/15/15 10.23† First Amendment to License Agreement dated January 8, 2018 between the Registrant and AveXis, Inc. 10-K 10.24 3/6/18 10.24† Collaboration and License Agreement dated September 10, 2021 between the Registrant and AbbVie Global Enterprises Ltd. 10-Q 10.1 11/2/21 10.25† First Amendment to Collaboration and License Agreement dated August 5, 2025 between the Registrant and AbbVie Global Enterprises Ltd. 10-Q 10.1 11/6/25 10.26† Collaboration and License Agreement dated January 14, 2025 between the Registrant and Nippon Shinyaku Co., Ltd. 10-Q 10.1 5/12/25 10.27 Lease dated March 6, 2015 between the Registrant and BMR-Medical Center Drive LLC S-1 10.26 8/17/15 10.28 First Amendment to Lease dated September 30, 2015 between the Registrant and BMR-Medical Center Drive LLC 10-K 10.31 3/3/16 10.29 Second Amendment to Lease dated November 23, 2015 between the Registrant and BMR-Medical Center Drive LLC 10-K 10.32 3/3/16 10.30 Third Amendment to Lease dated July 21, 2017 between the Registrant and BMR-Medical Center Drive LLC 10-Q 10.1 8/8/17 10.31 Fourth Amendment to Lease dated April 20, 2018 between the Registrant and BMR-Medical Center Drive LLC 10-Q 10.1 5/8/18 10.32 Fifth Amendment to Lease dated October 30, 2020 between the Registrant and ARE-Maryland No. 45, LLC, as successor in interest to BMR-Medical Center Drive LLC 10-Q 10.3 11/4/20 10.33 Lease dated November 1, 2018 between the Registrant and ARE-Maryland No. 24, LLC 10-Q 10.1 11/7/18 10.34 Letter Agreement to Lease dated April 12, 2019 between the Registrant and ARE-Maryland No. 24, LLC 10-Q 10.3 5/7/19 10.35 First Amendment to Lease dated April 23, 2019 between the Registrant and ARE-Maryland No. 24, LLC 10-Q 10.4 5/7/19 139 Table of Contents Incorporated by Reference Exhibit Number Description Form Exhibit Number Filing Date Filed or Furnished Herewith 10.36 Second Amendment to Lease dated November 4, 2019 between the Registrant and ARE-Maryland No. 24, LLC 10-Q 10.1 11/5/19 10.37 Third Amendment to Lease dated October 30, 2020 between the Registrant and ARE-Maryland No. 24, LLC 10-Q 10.4 11/4/20 10.38† Royalty Purchase Agreement dated December 22, 2020 between the Registrant and entities managed by Healthcare Royalty Management, LLC 10-K 10.42 3/1/21 10.39† Loan Agreement dated May 16, 2025 between REGENXBIO RS LLC and affiliate of Healthcare Royalty Management, LLC 10-Q 10.4 8/7/25 19.1 Insider Trading Policy 10-K 19.1 3/13/25 21.1 Subsidiaries of the Registrant X 23.1 Consent of PricewaterhouseCoopers LLP, independent registered accounting firm X 31.1 Certification of the Chief Executive Officer, as required by Section 302 of the Sarbanes-Oxley Act of 2002 X 31.2 Certification of the Chief Financial Officer as required by Section 302 of the Sarbanes-Oxley Act of 2002 X 32.1 Certifications of the Chief Executive Officer and Chief Financial Officer as required by 18 U.S.C. 1350 X 97.1 Compensation Clawback Policy 10-K 97.1 2/27/24 101 The following materials from the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 formatted in Inline XBRL (eXtensible Business Reporting Language): (i) Consolidated Balance Sheets (ii) Consolidated Statements of Operations and Comprehensive Loss (iii) Consolidated Statements of Stockholders’ Equity (iv) Consolidated Statements of Cash Flows (v) Notes to Consolidated Financial Statements X 104 The cover page from the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 formatted in Inline XBRL (included in Exhibit 101) * Management contract or compensatory plan or arrangement. † Portions of this exhibit have been omitted. The certifications attached as Exhibit 32.1 that accompany this Annual Report on Form 10-K are not deemed filed with the SEC and are not to be incorporated by reference into any filing of REGENXBIO Inc. under the Securities Act or the Exchange Act, whether made before or after the date of this Annual Report on Form 10-K, irrespective of any general incorporation language contained in such filing. 140 Table of Contents SIGNATURES Pursuant to the requirements of Section 13 and 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized on March 5, 2026. REGENXBIO INC. By: /s/ Curran Simpson Curran Simpson President and Chief Executive Officer Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. Signature Title Date /s/ Curran Simpson President, Chief Executive Officer and March 5, 2026 Curran Simpson Director (Principal Executive Officer) /s/ Mitchell Chan Chief Financial Officer March 5, 2026 Mitchell Chan (Principal Financial and Accounting Officer) /s/ Kenneth T. Mills Chairman of the Board of Directors March 5, 2026 Kenneth T. Mills /s/ Jean Bennett Director March 5, 2026 Jean Bennett /s/ Allan M. Fox Director March 5, 2026 Allan M. Fox /s/ Alexandra Glucksmann Director March 5, 2026 Alexandra Glucksmann /s/ A.N. “Jerry” Karabelas Director March 5, 2026 A.N. “Jerry” Karabelas /s/ George Migausky Director March 5, 2026 George Migausky /s/ David C. Stump Director March 5, 2026 David C. Stump /s/ Daniel Tassé Director March 5, 2026 Daniel Tassé /s/ Jennifer Zachary Director March 5, 2026 Jennifer Zachary 141