Meta-analysis of the efficacy and safety of Sativex (nabiximols), on spasticity in people with multiple sclerosis

Objective: To determine the efficacy of Sativex (USAN: nabiximols) in the alleviation of spasticity in people with multiple sclerosis. Methods: The results from three randomized, placebo-controlled, double-blind parallel group studies were combined for analysis. Patients: 666 patients with multiple sclerosis and spasticity. Measures: A 0-100 mm Visual Analogue Scale (VAS, transformed to a 0-10 scale) or a 0-10 Numerical Rating Scale (0-10 NRS) was used to measure spasticity. Patients achieving a >= 30% improvement from baseline in their spasticity score were defined as 'responders'. Global impression of change (GIC) at the end of treatment was also recorded. Results: The patient populations were similar. The adjusted mean change of the numerical rating scale from baseline in the treated group was -1.30 compared with -0.97 for placebo. Using a linear model, the treatment difference was -0.32 (95% CI -0.61, -0.04, p = 0.026). A statistically significant greater proportion of treated patients were responders (odds ratio (OR) = 1.62, 95% CI 1.15, 2.28; p = 0.0073) and treated patients also reported greater improvement: odds ratio 1.67 (95% CI 1.05, 2.65; p = 0.030). High numbers of subjects experienced at least one adverse event, but most were mild to moderate in severity and all drug-related serious adverse events resolved. Conclusion: The meta-analysis demonstrates that nabiximols is well tolerated and reduces spasticity.