FDA greenlights GW's Epidiolex, the first U.S. drug made from marijuana

The FDA just approved Epidiolex, the GW Pharma seizure drug derived from cannabis, giving children with two rare and serious forms of epilepsy a new treatment—and companies looking to develop marijuana-based drugs a model for their own path to market.

The agency approved Epidiolex, or purified cannabidiol, to treat Lennox-Gastaut syndrome and Dravet syndrome in patients 2 and older. The conditions typically begin in childhood, with frequent or prolonged seizures, and patients have a high risk of death from seizure-related causes and infections. Though other drugs are approved to treat Lennox-Gastaut syndrome, Epidiolex is the first licensed to treat Dravet syndrome.

GW Pharma won't be able to launch the drug right away, however, because its active ingredient, CBD, needs to be rescheduled by the DEA. Though CBD doesn't induce the high associated with marijuana use—THC does that—it's now classified as Schedule I, a category that covers drugs with no therapeutic value and high probability of abuse. The company said it expects the DEA to act "within 90 days" and plans to roll out the drug this fall.

On a call with reporters on Monday, FDA Commissioner Scott Gottlieb, M.D., cautioned that Epidiolex's green light is not an approval for marijuana but an approval for "one specific CBD medication for a specific use" based on well-controlled clinical trials. And Epidiolex could well be the first in a wave of marijuana-based therapies; agency officials said they have implemented regulatory processes to help drug developers test marijuana or its components in their own clinical trials.

Epidiolex's approval doesn't mean other CBD substances are OK to sell, Gottlieb said. The agency will continue to crack down on companies selling the compound for unproven medical claims.

The U.S. approval for Epidiolex was largely expected after an FDA advisory panel endorsed it with a 13-0 vote in April. Before the panel meeting, FDA staff also backed the drug in their own report, saying the company offered "substantial evidence" of efficacy. In three clinical trials covering 516 patients with either form of epilepsy, Epidiolex plus other antiepileptic medications reduced the frequency of seizures. In a note to clients after the approval, Evercore ISI analyst Josh Schimmer said the drug's label "reads clean, with no black box warnings or unexpected restrictions."

Epidiolex is under review in Europe as well, and GW expects a decision from the European Medicines Agency in the first quarter of next year. 

Aside from Epidiolex, GW Pharma also sells Sativex—which includes components of marijuana—in 30 countries as a treatment for multiple sclerosis-related spasticity. It's in phase 3 testing for a potential approval in the U.S. The company is also working on cannabinoid programs against glioblastoma, schizophrenia and more.

Other companies working with cannabidiol include AXIM Biotechnologies and Cure Pharmaceutical. In a statement, AXIM CEO George Anastossov said the approval is "highly encouraging for other pharmaceutical companies who are developing other naturally extracted, cannabinoid-based drugs for many other conditions.”

Editor's note: This story was updated with comments from Evercore ISI analyst Josh Schimmer and AXIM CEO George Anastossov.