A single-arm, open-label study of alemtuzumab in treatment-refractory patients with multiple sclerosis

Background: Alemtuzumab (CD52-specific humanized monoclonal antibody) was found to be an effective therapy for treatment-naive patients with relapsing-remitting multiple sclerosis. Objective: Evaluate alemtuzumab’s effects in patients with treatment-refractory relapsing-remitting multiple sclerosis. Methods: Forty-five relapsing-remitting multiple sclerosis patients who experienced ≥2 relapses during 2 years prior to the study entry whilst receiving interferon therapy were administered 24 mg IV alemtuzumab/day for 5 days at baseline and 3 days 12 months later. Patients received premedication with 1 g IV methylprednisolone on days 1–3 at both times. Results: After 2-year follow-up, the annualized relapse rate was reduced by 94% compared to pre-treatment levels, from 1.6 (2 years prior to treatment) to 0.17 for the 2 years following (P