Long-term B-lymphocyte depletion with rituximab in patients with relapsing-remitting multiple sclerosis.

OBJECTIVE To describe 2 patients with relapsing-remitting multiple sclerosis (RRMS) receiving long-term treatment with the monoclonal antibody rituximab. The clinical and paraclinical efficacy of rituximab was demonstrated recently in a phase 2 clinical trial in patients with RRMS. DESIGN Case series. SETTING Tertiary care university medical center. PATIENTS Two young patients with highly active RRMS in whom standard therapy had failed before receiving rituximab for up to 48 months. MAIN OUTCOME MEASURES Relapse rate, clinical disability, and results of magnetic resonance imaging. RESULTS Both patients tolerated rituximab treatment well and have been clinically stable throughout the study period. CONCLUSION Long-term therapy with rituximab appears safe and effective in some patients with RRMS. Our observation should be confirmed in controlled long-term trials.