NEW YORK – The US Food and Drug Administration has pushed back by about a month its decision on Sarepta Therapeutics' investigational Duchenne muscular dystrophy (DMD) gene therapy, the biopharmaceutical firm announced Wednesday.
The FDA has informed Sarepta that it "requires modest additional time" to review its application, "including final label negotiations and post-marketing commitment discussions." The agency was previously slated to issue a decision on SRP-9001(delandistrogene moxeparvovec) by May 29; regulators now expect to complete their review by June 22.
Based on its communication with the FDA, Sarepta is expecting the agency to potentially grant accelerated approval to SRP-9001 as a treatment for DMD patients ages 4 to 5 years old, initially. According to the Cambridge, Massachusetts-based company, the FDA also indicated that results from a Phase III trial that Sarepta proposed as a confirmatory study could be used to "entertain a non-age-restricted expansion of the SRP-9001 label."
SRP-9001 delivers a gene that encodes for microdystrophin to ambulatory patients with DMD who have a confirmed mutation in the DMD gene. Microdystrophin is an engineered protein developed by Sarepta that the firm says can carry out the normal functions of dystrophin — the protein perturbed in DMD patients.
Last September, Sarepta submitted to the FDA its biologics license application for SRP-9001, seeking accelerated approval based on how the gene therapy changed microdystrophin expression in patients as a surrogate endpoint. Reviewers from the FDA have raised doubts about the extent to which microdystrophin functions similarly to other dystrophin proteins and safety issues seen with the therapy. However, the FDA's Cellular, Tissue, and Gene Therapies Advisory Committee earlier this month narrowly voted in support of accelerated approval for SRP-9001, especially since the company is conducting the Phase III EMBARK study to confirm that SRP-9001 improves DMD patients' clinical outcomes.
Sarepta has finished enrolling the EMBARK trial and expects to share top-line results in Q4.