Fenfluramine for the Treatment of Dravet Syndrome and Lennox Gastaut Syndrome: A Review

Purpose of Review Treatment-resistant epilepsy comprises approximately 36.3% of neurology clinic-based populations in the USA. Despite new drug development over the past 50 years, the rates of drug-resistant epilepsy remain the same. The need for continued drug trials with novel mechanisms of action remains paramount in patients with drug-resistant epilepsy. In particular, patients with severe epilepsy syndromes such as Dravet syndrome (DS) and Lennox Gastaut syndrome (LGS) continue to be the most severely affected due to the increased rates of status epilepticus and sudden unexpected death (SUDEP). Recent Findings Fenfluramine has recently been FDA-approved for DS and LGS. There is substantial evidence highlighting the efficacy of fenfluramine in the treatment of seizures associated with DS and LGS. There are a growing number of studies investigating alternative uses of fenfluramine for treatment-resistant epilepsies. Summary The completed studies suggest that fenfluramine is both a safe and efficacious adjunctive therapy in the treatment of convulsive seizures and drop seizures associated with DS and LGS. Fenfluramine's suggested mechanism of action and available human evidence likely support its efficacy as an add-on therapy for more seizure types and calls for further research to expand its clinical use.