Sarepta Therapeutics Announces FDA Acceptance of Casimersen (SRP-4045) New Drug Application for Patients with Duchenne Muscular Dystrophy Amenable to Skipping Exon 45
Original press release, CAMBRIDGE, Mass., Aug. 25, 2020 (GLOBE NEWSWIRE)
Quickly
- FDA grants Priority Review Status and sets regulatory action date for February 25, 2021
- FDA has indicated it does not currently plan to hold an advisory committee meeting to discuss the application
- Received FDA’s conditional approval of AMONDYS 45™ as a brand name for casimersen
- Casimersen has been studied for the treatment of exon 45 amenable patients, approximately eight percent of patients with Duchenne
About the FDA Acceptance of Casimersen
Sarepta Therapeutics, Inc. announced the U.S. Food and Drug Administration (FDA) has accepted the Company’s New Drug Application (NDA) seeking accelerated approval for casimersen (SRP-4045) and provided a regulatory action date of February 25, 2021. The FDA has indicated it does not currently plan to hold an advisory committee to discuss the application. In addition, the Company has received conditional approval of AMONDYS 45 as the brand name for casimersen. Casimersen, a phosphorodiamidate morpholino oligomer (PMO), is engineered to treat patients with Duchenne muscular dystrophy (DMD) who have genetic mutations that are amenable to skipping exon 45 of the dystrophin gene.
The Company submitted its NDA filing in June 2020 and requested priority review, which the FDA granted. The NDA included data from the casimersen arm of the ESSENCE study (also known as Study 4045-301), a global, randomized, double-blind, placebo-controlled Phase 3 study evaluating the efficacy and safety of casimersen in patients amenable to skipping exons 45. An interim analysis from ESSENCE demonstrated a statistically significant increase in dystrophin production as measured by western blot in patients who received casimersen compared to baseline and placebo. The study is ongoing and remains blinded to collect additional efficacy and safety data.
Doug Ingram, president and chief executive officer, Sarepta Therapeutics – “The FDA’s acceptance of our NDA for casimersen is an important step toward our goal of rapidly bringing therapies to patients living with Duchenne muscular dystrophy. If it is approved, casimersen, our third exon-skipping medicine in our PMO RNA-based platform, will offer treatment to the 8% of Duchenne patients who are amenable to exon 45 skipping.”
About Casimersen
Casimersen uses Sarepta’s proprietary phosphorodiamidate morpholino oligomer (PMO) chemistry and exon-skipping technology to skip exon 45 of the Duchenne gene. Casimersen is designed to bind to exon 45 of dystrophin pre-mRNA, resulting in exclusion, or “skipping,” of this exon during mRNA processing in patients with genetic mutations that are amenable to exon 45 skipping. Exon skipping is intended to allow for the production of an internally truncated dystrophin protein. Read more here.
About the ESSENCE Study
The ESSENCE study is a double-blind, placebo-controlled, multi-center Phase 3 study evaluating the efficacy and safety of casimersen (SRP-4045) and golodirsen (SRP-4053, approved as VYONDYS 53™). Eligible patients with out-of-frame deletion mutations amenable to exon 45 or 53 skippings are randomized to receive once-weekly intravenous (IV) infusions of 30 mg/kg of SRP-4045 or 30 mg/kg of SRP-4053, respectively (combined-active group) or placebo for up to 96 weeks. This is followed by an open-label extension period in which all patients will receive open-label active treatment for 48 weeks, up to week 144 of the study.
Clinical efficacy is being assessed at regularly scheduled study visits, including functional tests such as the six-minute walk test (6MWT). All patients undergo a muscle biopsy at baseline and will undergo a second muscle biopsy either at week 48 or week 96.
Safety is being assessed through the collection of adverse events, laboratory tests, electrocardiograms (ECGs), echocardiograms (ECHOs), vital signs, and physical examinations throughout the study.
About Sarepta Therapeutics
The Company has built an impressive position in Duchenne muscular dystrophy (DMD) and in gene therapies for limb-girdle muscular dystrophies (LGMDs), mucopolysaccharidosis type IIIA, Charcot-Marie-Tooth (CMT), and other CNS-related disorders, with more than 40 programs in various stages of development. The Company’s programs and research focus span several therapeutic modalities, including RNA, gene therapy and gene editing. For more information, please visit www.sarepta.com or follow them on Twitter, LinkedIn, Instagram and Facebook.
More about DMD
DMD is caused by genetic mutations that prevent dystrophin production. Patients with DMD experience progressive and irreversible muscle loss with symptoms appearing as early as two years of age.
Duchenne muscular dystrophy occurs primarily in males. Early signs of DMD may include delayed ability to sit, stand or walk. There is a progressive loss of mobility, and by adolescence, patients with DMD may require the use of a wheelchair. Cardiac and respiratory muscle problems begin in the teenage years and lead to serious, life-threatening complications. Read more here.
