GW Pharmaceuticals has begun recruiting patients into a second late-stage trial evaluating the potential of its cannabinoid drug Epidiolex in treating a rare and severe form of treatment-resistant childhood epilepsy called Dravet syndrome.

The 14-week, Phase III study will compare two different strengths of Epidiolex to placebo in 150 patients to determine its safety and efficacy as an adjunctive anti-epileptic treatment. 

The primary endpoint is the percentage change from baseline in convulsive seizure frequency during the maintenance period, but several additional outcome measures will also be analysed, with top-line results expected early next year, the firm said. 

“Therapeutic options for patients with Dravet syndrome are limited and GW is committed to bringing Epidiolex to the market as quickly as possible and to offering a new option to address this significant unmet need,” noted chief executive Justin Gover.

The firm is expecting to submit a New Drug Application in the US mid-2016.