GW Pharmaceuticals PLC said Thursday it has won a unanimous recommendation from a U.S. Food and Drug Administration advisory committee for the approval of its cannabis-derived drug epidiolex. Epidiolex -- which contains cannabidiol (CBD), rather than the psychoactive component of cannabis, THC -- is intended for seizures associated with two rare types of childhood epilepsy. If approved, the drug would be the country's first cannabis-derived drug and the first in a new category of epilepsy treatments. GW's Chief Executive Justin Gover welcomed the recommendation and said the drug would "provide an important treatment option for patients with LGS and Dravet syndrome, two of the most severe and treatment-resistant forms of epilepsy." More than 90% of patients with the conditions have multiple seizures every day, putting them at risk of falls and injury. The FDA commonly follows an advisory committee's recommendation, but there are exceptions. GW shares were halted for the news, but have gained 15% in the last 12 months, matching the S&P 500's gain.