Advances in the Management of Multiple Sclerosis Spasticity: Recent Clinical Trials

Background: Most patients with multiple sclerosis (MS) experience spasticity as the clinical course evolves. Associated symptoms include (often painful) spasms, urinary dysfunction and sleep disturbances. THC:CBD oromucosal spray (Sativex(R)) is approved for symptom improvement in adult patients with moderate to severe MS-related spasticity who have not responded adequately to other antispasticity medication and who demonstrate clinically significant improvement in spasticity-related symptoms during an initial trial of therapy. Summary: In pivotal clinical trials of THC:CBD oromucosal spray, a meaningful proportion of patients with treatment-resistant MS spasticity achieved clinically relevant improvement with active treatment versus placebo. The utility of a 4-week trial of therapy to identify patients who respond to treatment was demonstrated in an enriched-design study. THC:CBD oromucosal spray was well tolerated in these studies, with no evidence of effects typically associated with recreational cannabis use. In a subsequent post approval clinical trial, THC:CBD oromucosal spray had no statistically significant effect on cognition and mood compared with placebo. Moreover, after 50 weeks' treatment, approximately two-thirds of patients, physicians and caregivers reported improvement from baseline in spasticity based on global impressions of change. Key Messages: In phase III clinical trials, approximately one-third of MS patients with treatment-resistant spasticity had a clinically relevant and statistically significant response to THC:CBD oromucosal spray. In addition to a reduction in spasticity, responders experienced meaningful relief from associated symptoms. THC:CBD oromucosal spray was generally well tolerated and efficacy was maintained over the longer term. A post-approval clinical trial indicated no effect of THC:CBD oromucosal spray on cognition or mood after 50 weeks of use.