REGENXBIO's RGX-202 shows improved muscle force and resistance to damage in preclinical studies.

REGENXBIO's investigational gene therapy, RGX-202, has shown improved muscle force and resistance to damage in mice lacking dystrophin. The therapy, which includes the CT domain, demonstrated higher levels of microdystrophin protein compared to a construct without the CT domain. These findings support the positive functional data seen in the Phase I/II AFFINITY DUCHENNE trial. RGX-202 is a next-generation gene therapy for Duchenne muscular dystrophy.

July 2, 2025 - REGENXBIO Inc. (Nasdaq: RGNX) has announced the publication of preclinical results demonstrating the functional benefits of its investigational gene therapy, RGX-202, in Duchenne muscular dystrophy (Duchenne). The study, published in Molecular Therapy Methods and Clinical Development, compared a microdystrophin gene therapy construct with and without the C-terminal (CT) domain [1].

The preclinical trial evaluated two AAV vectors in mdx mice, a preclinical model of Duchenne. The results showed that the microdystrophin with the CT domain maintained higher levels in transduced muscles, recruited the dystrophin-associated protein complex more effectively to the muscle membrane, and increased muscle force and resistance to damage compared to the construct without the CT domain. These findings support the potential of RGX-202 to drive functional improvements in patients with Duchenne [1].

RGX-202 is the only investigational or approved microdystrophin gene therapy candidate for Duchenne that includes the CT domain, a key portion of dystrophin. The interim results from the Phase I/II AFFINITY DUCHENNE trial of RGX-202, reported in June 2025, showed consistent evidence of positively changing the disease trajectory of patients with Duchenne and a favorable safety profile [1].

REGENXBIO is currently 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 [1].

References:
[1] https://www.prnewswire.com/news-releases/regenxbio-announces-publication-of-preclinical-results-demonstrating-functional-benefits-of-novel-microdystrophin-construct-in-rgx-202-investigational-gene-therapy-for-duchenne-muscular-dystrophy-302502606.html