Stoke Therapeutics Launches Global Phase III Trial of Zorevunersen for Dravet Syndrome.

Stoke Therapeutics and Biogen have initiated the global Phase III EMPEROR trial of zorevunersen (previously known as STK‑001) for children and adolescents with Dravet syndrome. This pioneering antisense oligonucleotide is designed to boost expression of the healthy SCN1A gene, potentially addressing not just seizure frequency but also cognitive and behavioral impairments. The study will enroll approximately 150 patients across the United States, United Kingdom, Europe, and Japan. Participants will undergo 8 weeks of baseline monitoring followed by 52 weeks of treatment, beginning with two 70 mg loading doses and transitioning to two 45 mg maintenance doses. The primary outcome measure is the reduction in major motor seizure frequency, with secondary outcomes assessing improvements in behavior and cognition via standardized tools such as Vineland‑3 subscales.

This trial marks a major milestone: zorevunersen holds FDA Breakthrough Therapy, orphan drug, and rare pediatric disease designations, while regulatory alignment has been secured with the FDA, EMA, and PMDA. The first patient has now been dosed, and data are expected by the second half of 2027. If successful, zorevunersen could become the first disease‑modifying therapy for Dravet syndrome.