Rituximab stabilizes multifocal motor neuropathy increasingly less responsive to IVIg.

The authors report a patient with anti-GM(1) antibody-negative multifocal motor neuropathy (MMN) who was increasingly less responsive to IV immunoglobulins (IVIgs). Five yearly courses of the monoclonal anti-CD20 antibody rituximab were well tolerated and extended the interval of IVIg administration from 7 to 12 days (corresponding to 42% reduction of IVIg) during this period. Rituximab may be a benefit for patients with MMN.