Zorevunersen (STK-001) - (EMPEROR)

June 30, 2026: Stoke Therapeutics (NASDAQ: STOK) announced completion of enrollment (162 patients) in the Phase 3 EMPEROR study (NCT06872125) of zorevunersen, an investigational antisense oligonucleotide for Dravet syndrome (SCN1A variants not associated with gain-of-function). The global, double-blind, sham-controlled trial randomizes children ages 2 to <18 (1:1) to intrathecal zorevunersen vs sham for 52 weeks; the primary endpoint is percent change from baseline in major motor seizure frequency at Week 28, with secondary endpoints including durability plus cognition/behavior measures assessed at Week 52 (Vineland-3 subdomains, among others). The study will remain blinded with final analysis after the 52-week period.

Stoke expects to initiate a rolling U.S. NDA submission to the FDA in Q1 2027; a Phase 3 data readout is anticipated in Q3 2027 to complete the rolling NDA submission in 2H 2027, with a stated goal of potential FDA approval and U.S. launch by early 2028. About 50 patients have reached 28 weeks of treatment, and no patients have discontinued. An additional ~30-patient European cohort is enrolling (last patient expected in August); China site activation is underway following Breakthrough Therapy Status there, but Europe/China data are not planned for inclusion in the U.S. NDA. Stoke noted a collaboration with Biogen (NASDAQ: BIIB) for development/commercialization (Stoke retains U.S./Canada/Mexico rights; Biogen holds rest-of-world rights).