REGENXBIO Inc. has reached two major milestones in its Duchenne muscular dystrophy (DMD) program — completing enrollment in the pivotal AFFINITY DUCHENNE trial and successfully manufacturing the first batches of RGX-202 intended for commercial use.
A Step Closer to Transformative Gene Therapy for Duchenne
RGX-202 is an investigational gene therapy designed to deliver durable benefits for patients with Duchenne muscular dystrophy — a rare, progressive, and life-limiting muscle disease.
The company’s goal: to bring a best-in-class treatment that meaningfully alters the disease course and expands long-term outcomes for patients with limited options.
“Completing this pivotal trial milestone and producing our first commercial batches bring us closer to delivering RGX-202 to patients who need it most,”
— Curran Simpson, President and CEO, REGENXBIO
Inside the AFFINITY DUCHENNE Trial
- Design: Multicenter, open-label Phase I/II/III study
- Enrollment: 30 participants completed in October 2025
- Primary Endpoint: Proportion of participants with ≥10% RGX-202 microdystrophin expression at Week 12
- Secondary Endpoints: Changes in timed function tests (ages ≥4), PDMS-3 and SV95C (ages 1–4)
The trial continues enrolling ambulatory participants aged 1 year and older in the confirmatory phase. Topline data are expected in early Q2 2026.
Promising Early Results
In the Phase I/II portion:
- Microdystrophin levels ranged from 20% to 122% of normal.
- No serious adverse events were reported.
- Participants showed consistent functional improvement versus external controls.
Scaling for Commercial Launch
REGENXBIO has manufactured the first commercial-ready batches of RGX-202 at its Manufacturing Innovation Center in Rockville, Maryland.
Using its proprietary NAVXpress® suspension-based process, the company achieved industry-leading product purity (>80% full capsids) — the highest among Duchenne gene therapies.
This platform enables the production of up to 2,500 doses per year, supporting a potential commercial launch in 2027.
What Makes RGX-202 Different
- Unique microdystrophin construct encoding key regions of natural dystrophin, including the C-Terminal (CT) domain
- Codon optimization for improved gene expression and reduced immunogenicity
- Targeted delivery via the NAV AAV8 vector and muscle-specific Spc5-12 promoter
- High-yield, commercial-ready manufacturing process (NAVXpress®)
Together, these features position RGX-202 as a potentially best-in-class gene therapy capable of durable, safe, and scalable impact in Duchenne.
