SRP-9001 has shown safety and efficacy across multiple studies compared to controls, with additional efficacy data expected in 2024 from the EMBARK trial.
Sarepta Therapeutics has submitted its biologics license application (BLA) for SRP-9001 (delandistrogene moxeparvovec), an investigational gene therapy developed in collaboration with Roche, for the potential treatment of ambulant patients with Duchenne muscular dystrophy (DMD).1
SRP-9001 expresses the microdystrophin gene to combat the deleterious effects of the dysfunctional dystrophin produced in DMD. It has been granted fast track, rare pediatric, and orphan drug designations in the US as well as orphan drug status in the EU, Switzerland, and Japan. The BLA has been submitted using the accelerated approval pathway.
“Every hour of every day, this ruthless disease, Duchenne, robs thousands of children in the United States of muscle as it steals their future from them. Sarepta’s BLA submission for an accelerated approval of SRP-9001 is a significant milestone in our quest to intervene with urgency on behalf of the children we serve,” Doug Ingram, president and chief executive officer, Sarepta Therapeutics, said in a statement.1 “If approved, SRP-9001 will be the first gene therapy available for Duchenne patients. We are enormously grateful to the courageous families who have participated in the SRP-9001 trials and to the participating clinical investigators and experts who have guided us and played a crucial part in reaching this milestone.”
THE BLA is based on positive data from the phase 1/2 Study SRP-9001-101 (NCT03375164), the phase 2 SRP-9001-102 study (NCT03769116), and the phase 1 ENDEAVOR study (SRP-9001-103; NCT04626674). At 1, 2, and 4 years after treatment, SRP-9001 was well-tolerated and yielded clinical improvements and biomarker expression. Sarepta also found evidence of clinical benefit by comparing an integrated analysis across the 3 studies to an external control.
Biomarker findings were obtained by western blot and supported by immunofluorescence. Efficacy and clinical benefits were measured by the North Star Ambulatory Assessment (NSAA) and secondary timed tests.
SRP-9001 is currently being evaluated in the double-blind, randomized, plscaebo-controlled EMBARK study (Study SRP-9001-301; NCT05096221), which is being proposed at the post-marketing confirmatory study to support the accelerated approval. EMBARK is primarily assessing change in NSAA total score from baseline to week 52 compared to placebo. Secondary outcomes include microdystrophin expression, time to rise from floor, patient-reported outcomes, skills gained, incidence of adverse events, and changes in scores on 100- and 10-meter walk/run, Timed Stair Ascend 4 Steps, and Stride Velocity 95th Centile tests.
“The data from our 103 study is particularly important because it’s from our commercially-representative material,” Louise Rodino-Klapac, PhD, executive vice president and chief scientific officer, Sarepta, said on a conference call regarding data on July 6, 2022.2 “It can be extremely challenging to achieve the same level of safety and efficacy when scaling up from small-scale to commercial-scale, so we are thrilled to see that these results are not only consistent, but may be improved over previously reported results.”