Treatment of IgM antibody associated XXXX using rituximab.

@entity1 @entity4094 @entity2225 @entity305 @entity1897
OBJECTIVES: @entity305 with associated serum IgM antibodies are often difficult to treat. Rituximab is a monoclonal antibody directed against the B cell surface membrane marker @entity2225 . Rituximab eliminates B cells from the circulation, and, over time, could reduce cells producing autoantibodies. This study tested the ability of rituximab to produce changes in serum antibody titres, and improvement in strength, in @entity1 with @entity4094 and IgM autoantibodies. METHODS: Over a period of two years, the authors evaluated changes in strength, measured by quantitative dynamometry, and concentrations of several types of serum antibodies in @entity1 with @entity305 and serum IgM autoantibodies. Twenty one @entity1 treated with rituximab were compared with 13 untreated controls. RESULTS: Treatment with rituximab was followed by improved strength (an increase of mean (SEM) 23% (2%)of normal levels of strength), a reduction in serum IgM autoantibodies (to 43% (4%) of initial values), and a reduction in total levels of IgM (to 55% (4%) of initial values). There was no change in levels of serum IgG antibodies. There were no major side effects, even though B cells were virtually eliminated from the circulation for periods up to two years. CONCLUSIONS: In @entity1 with IgM autoantibody associated @entity1897 , rituximab treatment is followed by reduced serum concentrations of IgM, but not IgG, antibodies, and by improvement in strength. Additional studies, with placebo controls and blinded outcome measures, are warranted to further test the efficacy of rituximab treatment of IgM associated @entity305 .
