The U.S. Food and Drug Administration may be on the verge of approving its first prescription drug derived directly from marijuana.
In a report posted online, FDA staff said there was “substantial evidence” that Epidiolex, a liquid formula containing cannabidiol (CBD), was effective in reducing seizures in children with Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS), two severe forms of childhood epilepsy.
Epidiolex is made by GW Pharmaceuticals, a British drug maker that specializes in developing drugs from marijuana.
“The applicant has provided positive results from three randomized, double-blind, placebo-controlled studies conducted in patients with LGS and DS,” FDA staff reported.
“The studies are adequate and well-controlled. The statistically significant and clinically meaningful results from these three studies provide substantial evidence of the effectiveness of CBD for the treatment of seizures associated with LGS and DS.”
CBD is one of the active ingredients in marijuana. It does not contain THC (tetrahydrocannabinol), the chemical compound in marijuana that makes people high. Many oils and tinctures containing CBD are already sold online and in states were medical marijuana is legal, but the FDA has not approved any of them. The agency has only approved a handful of synthetic cannabinoids such as Marinol (dronabinol) to treat loss of appetite and nausea.
Although some children in the clinical trials experienced side effects from Epidiolex such as liver toxicity, anemia and drowsiness, the FDA staff report said the risks were “mild to moderate” and could be managed with warning labels. The report also found there was low risk of Epidiolex being abused.
“Although the review is still ongoing, the risk-benefit profile established by the data in the application appears to support approval of cannabidiol for the treatment of seizures associated with LGS and DS,” the report concludes.
An FDA advisory committee will consider GW Pharmaceutical’s application on Thursday. In a briefing paper for the committee, the company said there were few effective treatment options for children with LGS and DS, who often have severe intellectual and developmental disabilities and high risk of mortality.
A final decision by the agency is expected this summer. If Epidiolex is approved, it would technically only be for the treatment of childhood epilepsy. However, doctors would be free to prescribe it “off label” for other conditions such as chronic pain.
GW Pharmaceuticals also makes Sativex, an oral spray that contains both CBD and THC. Sativex has been approved in Europe, Canada, Australia, New Zealand and several other countries for the treatment of muscle spasticity caused by multiple sclerosis. In Israel, Sativex is also approved for the treatment of pain and chronic non-cancer pain.