Sarepta Therapeutics announced that the U.S. FDA has removed the clinical hold on the company's investigational peptide-conjugated phosphorodiamidate morpholino oligomer (PPMO) to treat patients with Duchenne muscular dystrophy after Sarepta agreed to adjust the global trial protocol to include expanded monitoring of urine biomarkers.
The hold was placed on part B of the phase 2 MOMENTUM trial back in June, after a serious adverse event of low magnesium, known medically as hypomagnesemia. At the time, the FDA requested information on all cases of hypomagnesemia, including a small number of non-serious grade 2 cases, and to assess the adequacy of the risk mitigation and safety monitoring plan.
SRP-5051 (vesleteplirsen) is an investigational agent using Sarepta’s proprietary PPMO chemistry and exon-skipping technology to skip exon 51 of the dystrophin gene. The treatment is designed to bind to exon 51 of dystrophin pre-mRNA, resulting in exclusion of this exon during mRNA processing in patients with genetic mutations that are amenable to exon 51 skipping.
Sarepta said it will implement the changes in the trial protocol and resume dosing in the U.S. as quickly as possible.