REGENXBIO, a pharmaceutical company developing gene therapies for a variety of diseases, recently announced encouraging clinical trial results for their gene therapy for Duchenne muscular dystrophy (DMD), RGX-202.
“RGX-202 is a potential best-in-class investigational gene therapy designed for improved function and outcomes in Duchenne,” wrote REGENXBIO.
The drug works by delivering a shortened version of the dystrophin protein called microdystrophin to cells. RGX-202 encodes key regions of the dystrophin protein, including those necessary for muscle repair.
The AFFINITY DUCHENNE clinical trial aims to evaluate the safety and efficacy of RGX-202 in patients with DMD. In their recent press release, REGENXBIO provided updates on the first five patients enrolled in the trial, who were aged six to 12 years old.
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At nine months post-treatment, the participants experienced significant improvements in several functional measures of disease progression (including time to stand, performance on a 10-meter walk/run test and time to climb) compared to individuals with DMD not enrolled in the trial.
Of the five participants, four remained in the trial at 12 months post-dosing. The patients continued to experience improved functional performance compared to controls, on average.
Additionally, biomarker analysis demonstrated high levels of microdystrophin expression across all ages. “New data from an additional patient, aged [two] at dosing, had a microdystrophin expression level of 118.6% compared to control,” the company said.
No serious adverse effects were experienced by participants. Some individuals experienced fatigue, nausea and vomiting, which are relatively common side effects of gene therapy administration.
The trial is currently enrolling individuals with DMD aged one year and older in the United States and Canada and hopes to enroll a total of 30 patients this year.
REGENXBIO plans to submit a Biologics License Application for RGX-202 to the U.S. Food and Drug Administration in mid-2026, which is required to market the drug in the United States.
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