Sarepta Therapeutics (SRPT) Status Update summary

Two-year EMBARK study results and clinical efficacy

• Two-year follow-up of the EMBARK trial showed sustained, statistically significant functional benefits in Duchenne muscular dystrophy patients, with improvements in NSAA, time to rise, and 10-meter walk/run compared to external controls.

• MRI data at two years demonstrated minimal progression in muscle pathology and lower fat infiltration and inflammation in treated patients, supporting the observed functional improvements and emphasizing early intervention.

• Statistically significant and clinically meaningful benefits were maintained or increased over time, indicating disease stabilization and divergence from natural DMD progression.

• All patients remained ambulatory over two years, with no new safety signals; adverse events were consistent with previous findings and mostly occurred in the first year.

• ELEVIDYS is contraindicated in patients with deletions in exon 8 and/or exon 9 of the DMD gene.

Safety and tolerability

• No new safety signals were observed; the safety profile remains consistent and manageable, with most common adverse reactions being vomiting, nausea, liver injury, pyrexia, and thrombocytopenia.

• Important precautions include monitoring for infusion-related reactions, acute liver injury, immune-mediated myositis, and myocarditis.

Study design and regulatory status

• EMBARK is a multinational, phase 3, randomized, double-blind, placebo-controlled, two-part crossover study in DMD patients aged 4–7 years, with primary endpoint being change in NSAA at 52 weeks; after crossover, all patients received Elevidys, necessitating external controls for year two comparisons.

• Propensity-weighted external control cohorts were used to match key prognostic factors, allowing robust statistical comparisons for NSAA, time to rise, and 10-meter walk/run.

• ELEVIDYS is approved for DMD patients aged four and older in the US and several other countries, with ongoing collaboration between Sarepta and Roche for global access; continued approval for non-ambulatory patients is contingent on confirmatory trials.