US precision medicine company Sarepta Therapeutics has announced the US Food and Drug Administration (FDA) has accepted its new drug application (NDA) for its Duchenne muscular dystrophy (DMD) drug Golodirsen (SRP-4053).

The FDA also granted Golodirsen priority review, with regulatory action expected in August 2019.

The decision is based upon results from the 4053-101 study in which Sarepta’s drug met all biological endpoints.

DMD is a life-threatening neuromuscular disorder caused by a mutation in the dystrophin gene. Golodirsen is one of a range of therapies in Sarepta’s pipeline designed to skip an exon in the dystrophin pre-mRNA, which allows a shortened form of protein to be synthesised. Golodirsen skips exon 53.

Sarepta president and CEO Doug Ingram said: “If approved, Golodirsen will serve up to another 8 percent of the Duchenne community, bringing us closer to helping as many Duchenne patients as possible.”

“We look forward to working with the FDA toward advancing this important therapy and rapidly bringing it to individuals with Duchenne who are amenable to exon 53 skipping.”

Golodirsen is also being investigated in the Essence (4045-301) trial for DMD in combination with another of the company’s exon skipping products, Casimersen, which skips exon 45.

Sarepta and its partner gene therapy company Lysogene have also announced the dosing of the first patient in their Phase II/III clinical trial investigating LYS-SAF302 for Mucopolysaccharidosis Type IIIA (MPS IIIA).

LYS-SAF302 is a recombinant adeno-associated virus vector carrying the N-sulfoglucosamine sulfohydrolase gene, mutations in this gene causes MPS IIIA.

Lysogene founder and CEO Karen Aiach said: “The first patient dosed in the AAVance trial is an important step in addressing this relentlessly progressing neurodegenerative disease.

“Our aim is to stabilize or improve the clinical status of patients with MPS IIIA by providing a permanent source of functional enzyme in the brain.”