Business Wire·Mar 4, 2026, 5:06 PM ET

The New England Journal of Medicine Publishes First Data to Demonstrate the Potential for Disease Modification in Dravet Syndrome

BIIB STOK

Stoke Therapeutics and Biogen announced publication of zorevunersen data in The New England Journal of Medicine from Phase 1/2a studies and open-label extensions.
Results demonstrate substantial, durable reductions in major motor seizure frequency & improvements in cognition, behavior, & quality of life for Dravet syndrome patients treated with zorevunersen plus standard anti-seizure medicines.
Clinical benefits observed in the initial Phase 1/2a period continued through three additional years of treatment in open-label extension studies.
The most significant seizure reductions occurred in patients receiving initial 70 mg doses of zorevunersen.
Zorevunersen is generally well-tolerated across 81 patients receiving over 800 doses, with the most common adverse event being elevated cerebrospinal fluid protein levels (44% in extensions) without related clinical manifestations.
One patient discontinued treatment due to elevated CSF protein, while all other serious adverse events were assessed as unrelated to the drug except for one suspected unexpected serious adverse reaction.
Zorevunersen is an investigational antisense oligonucleotide designed to increase NaV1.1 protein production from the unaffected SCN1A gene copy to address the underlying genetic cause of Dravet syndrome.
The drug holds orphan drug, rare pediatric disease, & Breakthrough Therapy designations from the FDA & EMA.
A global Phase 3 EMPEROR study is ongoing to evaluate efficacy, safety, & tolerability, with enrollment expected to complete in Q2 2026.
Data readout from the Phase 3 EMPEROR study is projected for mid-2027 to support a potential New Drug Application submission to the FDA.
Current treatments for Dravet syndrome do not modify the disease course, & up to 57% of patients fail to achieve a 50% reduction in seizure frequency with existing anti-seizure medicines.