GW shares rise on positive Epidiolex efficacy data

UK-based GW Pharmaceuticals (Nasdaq: GWPH) has announced physician reports of efficacy and safety data from its investigational cannabidiol (CBD) product candidate, Epidiolex. GW shares rose 15% to a record high of £4.30 yesterday on the news.

The treatment-resistant patients suffer from a range of epilepsies in which current anti-epileptic drugs have been unsuccessful in adequately controlling seizures, and included such severe forms of epilepsy as Dravet syndrome and Lennox-Gastaut syndrome. Uncontrolled data from two hospital sites in the USA that were generated under expanded access Investigational New Drug applications authorized by the US Food and Drug Administration were made available to the company.

Data were made available on 27 patients who have been treated with Epidiolex for at least 12 weeks. Two patients commenced treatment in 2013 and the remaining 25 patients commenced treatment in the first quarter of 2014. Treatment effect data have been calculated in a manner consistent with the FDA’s recommended endpoint for evaluating efficacy, which compares percent change in the average four week seizure frequency throughout the 12 week treatment period to seizure frequency during a four week baseline period. The same approach of average four week seizure frequency throughout the 12 week treatment period has been used in a responder analysis.