Epratuzumab (EMab, UCB, Immunomedics) is a humanized monoclonal antibody targeting CD22 that is being studied in clinical trials for patients with a variety of rheumatic and hematologic conditions, including systemic lupus erythematosus (SLE). An overview of its mechanism of action is followed by a summary of completed lupus studies, and a preview of studies in progress. The agent clearly has anti-inflammatory activity and is a potentially useful agent in the management of autoimmune disorders.
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