Chronic inflammatory demyelinating polyradiculoneuropathy and multifocal motor neuropathy: treatment update

PURPOSE OF REVIEW: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy usually respond to immune therapies including steroids and plasma exchange for CIDP and high-dose intravenous immunoglobulins (IVIgs) for both diseases. Other immune therapies have been used to reduce the costs or the side-effects of these therapies, but their efficacy was only recently assessed in randomized controlled trials (RCTs). RECENT FINDINGS: The prolonged efficacy of IVIg in CIDP has been confirmed in a 48-week RCT. Two other RCTs showed that oral methotrexate or intramuscular interferon beta were not more effective than placebo in improving the efficacy or reducing the dose of IVIg or steroids. In multifocal motor neuropathy, a RCT showed that oral mycophenolate mofetil was not more effective than placebo in increasing the efficacy or reducing the dose of IVIg. Other immune therapies were assessed in open trials in both diseases, but their efficacy remains unclear, even if in some patients a possible efficacy of rituximab was reported. Some preliminary studies suggest that subcutaneous immunoglobulin may be as effective as IVIg in the maintenance therapy of CIDP and multifocal motor neuropathy. SUMMARY: After several years of anecdotal reports, a number of RCT have now appeared in CIDP and multifocal motor neuropathy, but their results are still insufficient to support the use of new therapies in these diseases.