A Phase IIb Study of Nabiximols for Spasticity Due to Neuromyelitis Optica Spectrum Disorders

The goal of this clinical trial is to evaluate the safety and efficacy of nabiximols, a cannabinoid spray, for the treatment of moderate to severe spasticity in adult patients with AQP4-IgG positive and antibody-negative NMOSD. The main question it aims to answer is whether treatment with nabiximols improves patient-reported spasticity ratings compared to treatment with a placebo. This trial will also answer whether nabiximols impact pain, spasm frequency, mood, walking ability, and sleep. Participants will be mailed the treatments and placebo treatments, and will be asked to complete study visits and questionnaires remotely. There is also an optional sub-study that involves in-person visits with ultrasound imaging and in-person neurologic exams.