FDA advisers back GW's Epidiolex for rare epilepsy

UK-based GW Pharmaceuticals’ Epidiolex looks on course for approval in the US, after a panel of FDA experts unanimously backed it as a treatment for two rare forms of epilepsy.

The FDA's Peripheral and Central Nervous System Drugs Advisory Committee voted 13-0 in favour of approving Epidiolex (cannabidiol), for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS) and Dravet syndrome in patients two years of age and older.

Although the committee’s decision is not binding, the regulator usually follows the advice of its advisers, and is set to give a final verdict on Epidiolex before a legal deadline of June 27.

The FDA's staff reviewers had already given Epidiolex a clean bill of health in a briefing document prepared ahead of the meeting.

If approved Epidiolex will be the first pharmaceutical formulation of purified, plant-based cannabidiol, a cannabinoid lacking the high associated with marijuana, and the first in a new category of anti-epileptic drugs.

Analysts think Epidiolex could become a blockbuster drug if it is approved in a third indication, tuberous sclerosis, which GW is still researching.

LGS and Dravet develop in childhood and are devastating forms of epilepsy with high morbidity and mortality rates, placing a significant burden on families and caregivers.

More than 90% of patients with LGS or Dravet syndrome have multiple seizures per day, which puts them at constant risk from falls and injury.

Physicians who treat LGS and Dravet syndrome patients struggle to reduce the volume of dangerous seizures with currently available therapies. If approved, Epidiolex would be the first-ever FDA-approved medicine for Dravet syndrome patients.

During the meeting, the company presented the results of a robust clinical development program that included three randomised, controlled phase 3 clinical trials and an open label extension study.

In the phase 3 studies, Epidiolex added to other antiepileptic therapies significantly reduced the frequency of seizures in patients with LGS and Dravet syndrome.

Epidiolex was generally well tolerated with most adverse events reported as mild or moderate.