Long-Term Cardiovascular Safety of Fenfluramine HCl in the Treatment of Dravet Syndrome: Interim Analysis of an Open-Label Safety Extension Study

Introduction: In two recently completed Phase 3 clinical trials, fenfluramine (FFA) has demonstrated superior efficacy vs placebo for convulsive seizure reduction in children and young adults (2-18 years old) with Dravet syndrome (DS). FFA, previously marketed for weight loss, was withdrawn from the market in 1997 following reports of cardiac valvular heart disease (VHD) and pulmonary hypertension in obese adults treated with ≥60 mg/day. Here we report the cardiovascular safety findings from an interim analysis of the long-term safety extension study of low-dose FFA for DS in children and young adults.