FDA Panel Unanimously Backs Cannabis Drug for Severe Epilepsy

 A US Food and Drug Administration (FDA) advisory committee has voted unanimously to support approval of a purified formulation of cannabidiol (Epidiolex, GW Pharmaceuticals) as an adjunctive treatment for Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) in patients 2 years of age or older.

Although there are medications already on the market that include synthetic cannabinoid chemicals, if approved, this would be the first pharmaceutical formulation of a plant-based cannabinoid that maintains the mechanism of action of the chemical but without the "high" associated with marijuana, according to the manufacturer.

The Peripheral and Central Nervous System Drugs Advisory Committee had almost no concerns about the safety or effectiveness of Epidiolex, and congratulated the FDA, the manufacturer, and patients and families for having presented solid evidence.

"This is clearly a breakthrough drug for an awful disease," said panelist John Mendelson, MD, a senior research scientist at the Friends Research Institute, San Francisco, California.

"It's an honor to be part of a meeting that's making an important decision based on science and public input rather than a political discussion," said panel member Mark W. Green, MD, FAAN, professor of neurology, anesthesiology, and rehabilitation medicine, Icahn School of Medicine at Mt. Sinai, New York City.

"This is a historic moment," said Michael Privitera, MD, director of the epilepsy center at the University of Cincinnati, Ohio, who was an investigator for one of the pivotal studies. Privitera said he paid his own way to the meeting and receives no money from GW Pharmaceuticals. "We don't really understand how it stops seizures, but it's different than any other drug we've seen," he said, adding that it was rigorously studied.

"This will be more reliable than the dispensary marijuana that's available in many states," Privitera added.

The FDA usually follows its panels' advice. Billy Dunn, MD, director of the FDA's Division of Neurology Products, said the agency is "reviewing [Epidiolex] on an expedited timeline." The agency is due to make a decision by June 27. Epidiolex is also being reviewed by the European Medicines Agency, which accepted the company's application in February.

No Risk for Abuse

Even though Epidiolex is derived from marijuana (Cannabis sativa), it does not have properties conducive to abuse, said the FDA reviewers. That is crucial, because currently, Epidiolex is considered to be a Schedule I drug by the Drug Enforcement Administration (DEA). If the FDA approves Epidiolex, it will make a recommendation to the DEA that the drug be rescheduled.

If Epidiolex is rescheduled, GW Pharmaceuticals expects to make it available to physicians as soon as possible — most likely during the second half of this year — company CEO Justin Gover told Medscape Medical News. The company is proposing an initial target dose of 10 mg/kg daily, with dose adjustments up to 20 mg/kg, based on clinical response and tolerability.

One of the company's pivotal safety and efficacy trials in patients with LGS was published online January 24 in the Lancet. Data from that trial and two other pivotal studies were presented at the advisory panel meeting.

The primary endpoint — percentage reduction in drop seizures in LGS patients and percentage reduction in convulsive seizures in DS patients — was statistically significant for patients who received 14 weeks of treatment.