GW Pharmaceuticals plc, a biopharmaceutical company focused on discovering, developing and commercializing novel therapeutics from its proprietary cannabinoid product platform, has reported top-line results from a 12 month placebo-controlled study of Sativex in patients with spasticity due to multiple sclerosis (MS). The study results confirm the reassuring safety profile of Sativex and provide further evidence of long-term efficacy.

The study was a 12 month multi-centre, double-blind, randomised parallel group, placebo-controlled study in 121 patients with MS spasticity. The study was required as a post-approval commitment by the UK regulatory authority, the Medicines and Healthcare products Regulatory agency (MHRA), with the primary objective of evaluating whether Sativex may have long term adverse effects on cognitive function or mood. The primary endpoint was the change in cognitive function as assessed by the total Paced Auditory Serial Addition Test (PASAT) score from baseline to end of treatment. Mood was assessed by the Beck Depression Inventory-II.

There was a slight improvement in the PASAT score from the beginning to the end of the study in both the Sativex and placebo groups, thus confirming that there is no evidence of long-term cognitive impairment in patients taking Sativex compared with those taking placebo. Similarly, the change in mood over the 12 month period was more or less identical in the Sativex and the placebo group, confirming no untoward effect on mood.

The key efficacy secondary endpoints were the global impression of change scores as assessed by the patient, physician and carer. Each of these endpoints was highly significantly in favour of Sativex (p<0.0001, p=0.001 and p=0.004 respectively).

Detailed data from this study will be presented at the 29th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) on October 2-5 in Copenhagen, Denmark.

Dr Stephen Wright, GW’s R&D director, said, “We are pleased to report positive and wholly reassuring results from this 12 month placebo-controlled study in patients with MS spasticity. We have now shown that Sativex does not impair cognition either in short-term or in long-term use in well designed, randomised, placebo controlled clinical trials.  These data not only confirm the good tolerability of Sativex in long-term use but also provide further evidence of efficacy consistent with that seen in previous shorter duration clinical trials.”