GW Pharmaceuticals has kicked off a Phase III clinical trial of its cannabinoid Epidiolex for the treatment of Lennox-Gastaut syndrome (LGS), a rare and severe form of childhood-onset epilepsy.

Although there are approved treatments available for patients with LGS, “this severe form of epilepsy often remains particularly difficult to treat,” says Justin Gover, GW's chief executive, adding “we believe that Epidiolex has the potential to meet this significant unmet need”.

GW anticipates that top-line data from the 14-week, 150-patient trial, which closely follows the start of two late-stage studies assessing the drug in another rare childhood epilepsy called Dravet syndrome, will be available early next year.

Around 14,000-18,500 patients are estimated to suffer from LGS in the US, and 23,000-31,000 in Europe.