The Muscular Dystrophy Association (MDA) conference concluded in Orlando, Florida on March 12, bringing forward new research and clinical trial results from several biopharmaceutical companies focused on muscle disorders.
The event highlighted the latest advances in treatments for conditions such as spinal muscular atrophy (SMA), Becker muscular dystrophy (BMD), and Duchenne muscular dystrophy (DMD). These developments are significant for patients and families affected by these rare neuromuscular diseases, as they offer hope for improved therapies and outcomes.
Biogen announced that its antisense oligonucleotide therapy salanersen showed a substantial reduction—about 75%—in neurofilament light chain concentration among children with SMA in a Phase 1b study. The company said this effect was sustained through at least one year of follow-up. Twelve out of twenty-four treated patients achieved at least one new motor milestone after starting treatment, while all maintained their baseline motor skills. Biogen plans to advance an 80-mg dose of salanersen into a global Phase 3 program this year, which will include three studies targeting different age groups and stages of SMA.
Edgewise Therapeutics presented long-term data from its open-label MESA study on sevasemten for BMD. The drug candidate maintained stability outcomes over more than two years of follow-up compared to natural history controls whose performance declined. Analysts at Truist Securities said, "We believe the data continue to support sevasemten’s efficacy benefit in BMD, for which there are no approved therapies." Edgewise is conducting the pivotal GRAND CANYON trial with topline results expected later this year.
Sarepta Therapeutics shared a post-hoc analysis from the ESSENCE study showing that its exon-skipping drugs Vyondys 53 and Amondys 45 delayed motor decline by about 23 weeks versus placebo in DMD patients. Although these drugs failed to significantly improve motor function in the confirmatory Phase 3 trial last November, Sarepta said it would seek full FDA approval based on "encouraging trends" observed. Jefferies analysts said outcomes from the post-hoc analysis should "support FDA discussions in March 2026 on a path forward for full approval." Sarepta also presented three-year data from its EMBARK study of gene therapy Elevidys, supporting therapeutic benefits but noting previous safety concerns that led to additional warnings and restrictions.
