Sarepta Therapeutics today announced that the company is discontinuing its SRP-5051 (vesleteplirsen) development program, including the global, Phase 2, multi-arm, ascending dose MOMENTUM study. Vesleteplirsen is an investigational, next-generation treatment utilizing Sarepta’s PPMO chemistry and exon-skipping technology for individuals with Duchenne amenable to exon 51 skipping.

According to Sarepta, this decision was informed by information available to date, including the risk-benefit of the program, feedback from the FDA, and the evolving therapeutic landscape for Duchenne. Sarepta noted in their community letter that hypomagnesia (low blood levels of magnesium) was seen early in the study and considered manageable, but in a subset of patients this hypomagnesia was prolonged and persisted even after discontinuation of vesleteplirsen. They also noted a decline in a test for kidney function in some patients. While the expression of dystrophin seen with vesleteplirsen was encouraging, the long-term safety and tolerability measures influenced their decision.

PPMD is disappointed to learn of Sarepta’s news. We have reached out to Sarepta for more information and will update the community as soon as we are able. If you are an individual who was actively participating in a study with vesleteplirsen, we recommend you reach out to your study site for more information if needed.

We are grateful to all the families who have participated in clinical trials with vesleteplirsen, and to the Sarepta team for their work to advance therapy development in Duchenne. The discontinuation of a trial is always difficult for our community, but we remain hopeful that the data from this trial will inform other potential treatments and that these experiences will lead us to the day that we end Duchenne.

Read Sarepta’s community letter here.