Safety and Effectiveness of Nabiximols Oromucosal Spray as Add-on Therapy in Participants With Spasticity Due to Multiple Sclerosis

This multicenter, double-blind, placebo-controlled trial includes a 28-day Baseline period, a 12-week treatment period (comprising a 2-week titration phase and a 10-week maintenance phase), and 2-week follow-up period. Eligible participants will enter the 28-day baseline period. During baseline, participants will maintain their optimized oral MS antispasticity medication regimen and record spasm count using an electronic daily diary. At screening (Day 1), eligible participants will be randomized to either nabiximols or placebo in a 1:1 ratio. Participants will be advised to titrate the investigational medicinal product (IMP), beginning with 1 spray/day, to an optimized dose or to a maximum of 12 sprays/day over the first 14 days of treatment. Participants may leave a gap between sprays of approximately 15 minutes. Participants should continue at the same dose level achieved at the end of the titration phase ±1 spray divided into a morning dose and an evening dose for the remainder of the treatment period. Daily spasm count, the participant's symptom experiences, clinician's assessment of spasticity, functional outcomes, health-related quality of life, changes in mood, safety, tolerability, and pharmacokinetics will be evaluated during the treatment period. Participants who complete the trial will participate for a total of approximately 18 weeks (127 days), including the 28-day baseline period. Participants will have a maximum duration of 85 (±7) days on IMP treatment.