FDA approves Vyondys 53 injection for the treatment of Duchenne Muscular Dystrophy in patients amenable to skipping exon 53 .- Sarepta Therapeutics

Sarepta Therapeutics, Inc., announced that the FDA has approved Vyondys 53 (golodirsen). Vyondys 53 is an antisense oligonucleotide from Sarepta�s phosphorodiamidate morpholino oligomer (PMO) platform, indicated for the treatment of Duchenne muscular dystrophy (DMD) in patients with a confirmed mutation amenable to exon 53 skipping. This indication is based on a statistically significant increase in dystrophin production in skeletal muscle observed in patients treated with Vyondys 53, which is reasonably likely to predict clinical benefit for those patients who are exon 53 amenable. Consistent with the accelerated approval pathway, the continued approval of Vyondys 53 may be contingent on confirmation of a clinical benefit in this post-marketing confirmatory trial. Sarepta�s placebo-controlled, post-marketing confirmatory trial to support the Vyondys 53 accelerated approval � titled ESSENCE � is currently enrolling and expected to conclude by 2024.

Hypersensitivity reactions, including rash, pyrexia (fever), pruritis, urticaria (hives), dermatitis, and skin exfoliation have occurred in patients who were treated with Vyondys 53. Renal toxicity was observed in animal studies. Although not observed in the clinical studies with Vyondys 53, renal toxicity, including potentially fatal glomerulonephritis, has been observed after administration of some antisense oligonucleotides. The most common adverse reactions that occurred in at least 20% of Vyondys 53- treated patients and more frequently than in placebo-treated patients were headache (41%), pyrexia (41%), fall (29%), abdominal pain (27%), nasopharyngitis (27%), cough (27%), vomiting (27%), and nausea (20%).

Following a New Drug Application (NDA) submission to and review by the Division of Neurology Products (the Review Division) for Vyondys 53, which the Review Division recommended for approval, the Office of Drug Evaluation issued a complete response letter (CRL) in August of 2019. Thereafter, Sarepta made a formal dispute resolution request as outlined in relevant FDA Guidance. With the support of the Review Division, the matters raised in the CRL were rapidly evaluated and resolved by Dr. Peter Stein, Director of the Office of New Drugs (OND). OND granted the Company�s appeal and Sarepta re-submitted its NDA to the Review Division, which worked expeditiously to review and approve Vyondys 53.

�With the approval of Vyondys 53, up to another 8% of Duchenne families will have a therapy to treat this devastating disease,� said Pat Furlong, founding president and chief executive officer, Parent Project Muscular Dystrophy (PPMD). �