Efficacy of nabiximols oromucosal spray on spasticity in people with multiple sclerosis: Treatment effects on Spasticity Numeric Rating Scale, muscle spasm count, and spastic muscle tone in two randomized clinical trials

Background: To provide a comprehensive assessment of the treatment effects of nabiximols oromucosal spray on multiple sclerosis spasticity in two clinical trials, GWSP0604 and SAVANT. Methods: Both studies enriched for responders before randomization, defined by a ≥20% improvement in Spasticity 0-10 numeric rating scale (NRS) score. Additionally, SAVANT used randomized re-titration following washout. Spasticity NRS outcomes, spasm count, and modified Ashworth scale (MAS) scores were analyzed. Results: Mean change from baseline in average daily Spasticity NRS scores was significantly larger for nabiximols than placebo at all postbaseline timepoints, ranging from -0.36 to -0.89 in GWSP0604 and -0.52 to -1.96 in SAVANT. Percent reduction in geometric mean change from baseline in average daily spasm count for nabiximols ranged from 19–35% versus placebo. A treatment difference favoring nabiximols was observed in overall MAS scores during the randomized part of each study. Treatment effect was larger for combinations of lower limb muscle groups (ranging between -0.16 and -0.37). Conclusions: Nabiximols leads to improvement in spasticity that was sustained over the 12-week treatment period as measured by average daily Spasticity NRS scores, daily spasm counts, and MAS scores for combinations of muscle groups, especially the combination of the 6 key muscle groups in the lower limbs in NRS responders to nabiximols treatment.