US approves drug for rare childhood epilepsy

The U.S Food and Drug Administration on Thursday approved Zogenix’s drug to treat seizures associated with a rare form of childhood epilepsy known as Dravet syndrome.

The drug, branded as Fintepla, uses a low-dose liquid solution of fenfluramine, which was used in an obesity drug combination that was later withdrawn from the market due to evidence of heart valve damage.

The approval contains a boxed warning, the FDA’s harshest, flagging concerns about valvular heart disease and pulmonary arterial hypertension, and is available only through a restricted drug distribution program.

The agency last year had refused to fully review the marketing application for the treatment, and in February extended the application’s review by three months.

Dravet Syndrome, which affects about 1 in 15,700 individuals in the United States, causes long and frequent seizures that are difficult to control through antiepileptic medicines.

The approval pits Zogenix against GW Pharmaceutical’s cannabis-based drug, Epidiolex, which is also approved to treat seizures related to Dravet Syndrome and Lennox-Gastaut syndrome.

Fintepla is expected to bring in peak sales of about $450 million in about 5-7 years for its use against Dravet syndrome, according to Guggenheim analyst Yatin Suneja.

Zogenix is also testing Fintepla for treating Lennox-Gastaut syndrome.