A Study to Investigate the Safety and Effectiveness of Arbaclofen Extended-Release Tablets for Patients With MS

This is a multicenter, randomized, double-blind, placebo-controlled, parallel-group study to evaluate the safety and efficacy of oral AERT in MS patients with spasticity. Two doses of AERT, 40 mg and 80 mg, will be compared with placebo. The treatment groups will be randomized in a 1:1:1 ratio. Eligible patients will undergo a washout period for withdrawal of all medications used for anti-spasticity and/or muscle relaxation prior to randomization. A baseline clinical evaluation will be performed (Visit 2) to confirm eligibility for study randomization, and subjects will be randomly assigned to 1 of 3 treatment arms. Subjects will remain on maintenance treatment for approximately 3 months.