Investigational Low-Dose Fenfluramine Shows Promise in Phase 3 Trial for Dravet Syndrome
Phase 3 findings suggest that the investigational ZX008 (low-dose fenfluramine hydrochloride, Zogenix) is effective for the treatment of Dravet syndrome. The study enrolled 119 patients across sites in the US, Canada, Europe, and Australia with a median age of patients was eight years. Following a six-week baseline observation period, patients were randomized to one of three treatment groups: ZX008 0.8mg/kg/day (30mg maximum daily dose), ZX008 0.2 mg/kg/day and placebo in which ZX008 or placebo was added to current regimens of antiepileptic drugs. Patients were titrated to their target dose over two weeks and then remained at that fixed dose for 12 weeks. The mean baseline convulsive seizure frequency across the study groups was approximately 40 seizures per month. Patients taking ZX008 0.8 mg/kg/day achieved a 63.9% reduction in mean monthly convulsive seizures compared to placebo. The median percent reduction in monthly convulsive seizure frequency was 72.4% among ZX008 0.8mg/kg/day patients compared to 17.4% in placebo patients.
ZX008 is designated as an orphan drug in both the U.S. and Europe, and has received Fast Track designation in the U.S. for the treatment of Dravet syndrome. Zogenix is on track to submit applications for regulatory approvals in the US and Europe in the second half of 2018.