Summary

The presence of myositis-associated autoantibodies is the strongest predictor of improvement in patients with adult and juvenile myositis treated with B-cell depletion. This article describes findings from the Rituximab for the Treatment of Refractory Adult and Juvenile Dermatomyositis and Adult Polymyositis [RIM] study, in which baseline clinical, laboratory, and serologic predictors of response were examined in rituximab-treated patients with refractory myositis, defined as failure of steroids and at least 1 other immunosuppressive agent.