Fenfluramine may be a new treatment option for Dravet syndrome

When added to existing antiepileptic treatment, fenfluramine hydrochloride significantly reduced the frequency of convulsive seizures in children and young adults with Dravet syndrome and had a dose-response effect, according to a randomized trial in patients in whom seizures had not been completely controlled by their current treatment regimen.

The 119 patients, who ranged in age from 2 to 18 years, were assigned to 1 of 3 groups: existing antiepileptic treatment and 0.2 mg/kg per day of fenfluramine; existing antiepileptic treatment and 0.7 mg/kg per day of fenfluramine; or placebo. Existing antiepileptic drugs most often were valproate, clobazam, topiramate, and levetiracetam.

During the 14-week treatment period, seizure frequency declined by a median 74.9% in the fenfluramine 0.7 mg/kg group, 42.3% in the fenfluramine 0.2 mg/kg group, and 19.2% in the placebo group. Fenfluramine was associated with decreased appetite, diarrhea, lethargy, and sleepiness but not with development of any cardiovascular adverse events (Lagae L, et al. Lancet. 2020;394[10216];2243-2254).

Thoughts from Dr. Farber

It used to be that childhood epilepsy was believed to be due to obvious brain injury or was idiopathic. Now we are finding more genetic causes for seizures such as Dravet syndrome, and one can order genetic epilepsy panels to look for them. This in turn may lead to tailored treatment, as this article suggests.