Regenxbio Inc. Announces Publication of Preclinical Results Demonstrating Functional Benefits of Novel Microdystrophin Construct in Rgx-202 Investigational Gene Therapy for Duchenne Muscular Dystrophy

Published: 2025-07-10 13:50:32 ET RGNX

Published on 07/10/2025 at 13:50

REGENXBIO Inc. announced the publication of preclinical results comparing a microdystrophin gene therapy construct that included the C-terminal (CT) domain to a microdystrophin construct without the CT domain. The results, which were published in peer-reviewed journal Molecular Therapy Methods and Clinical Development, showed that the microdystrophin with the CT domain improved functional benefit compared to the microdystrophin without, supporting the potential of RGX-202 to drive functional improvements in patients with Duchenne Muscular Dystrophy. RGX-202 is the only investigational or approved microdystrophin gene Therapy candidate for the treatment of Duchenne muscular dystrophy (Duchenne) that includes the CT domain, a key portion of dystrophin, making it the closest to naturally occurring dystrophin.

These are key factors in supporting the preservation of muscle health, as muscle damage leads to disease progression in Duchenne. These findings indicate that incorporation of the CT domain enhances the microdystrophin design by allowing for higher levels of microdystrophin to accumulate in the muscle - primarily attributed to the longer half-life of the extended microdystrophin - and may improve the functional benefit of microdystrophin gene replacement. Interim results from the Phase I/II AFFINITY DUCHENNE clinical trial of RGX-202 reported in June 2025 show that RGX-202 demonstrated consistent evidence of positively changing the disease trajectory of patients with Duchenne and a favorable safety profile.

REGENXBIO is enrolling participants in the pivotal portion of the Phase I/II/III AFFINITY DUCHenNE trial of RGX-202 and expects to submit a Biologics License Application (BLA) using the accelerated approval pathway in mid-2026. These statements express a belief, expectation or intention and are generally accompanied by words that convey projected future events or outcomes such as "believe," " may, "will," "estimate," "continue," "anticipate," "assume," " design," "intend," "plan," "pot potential," "seek," "seek," "should," "would" or by variations of such words or by similar expressions. The forward-looking statements include statements relating to, among other things, REGENXBIO's future operations and clinical trials.

REGENXBIO has based these forward-looking statements on its current expectations and assumptions and analyses made by REGENXBIO in light of its experience and its perception of historical trends, current conditions and expected future developments, as well as other factors, as well as other factors. REGENXBIO believes are appropriate under the circumstances. However, whether actual results and developments will conform with REGENXBIO's expectations and predictions is subject to a number of risks and uncertainties, including the timing of enrollment, commencement and completion and the success of clinical trials conducted by REGENXBIO, its licensees and its partners, the timely development and launch of new products, the ability to obtain and maintain intellectual property protection for product candidates and technology, trends and challenges in the business and markets in which REGENXBIO operates, the size and growth of potent ial markets for product candidates and the ability to serve those markets, the rate and degree of acceptance of product candidates, and other factors, many of which are beyond the control of REGENXBIO.

refer to the "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" sections of REGENXBIO's Annual Report on Form 10-K for the yearended December 31, 2024.