Depletion of B cells in 17 patients with refractory autoimmune diseases

17 patients with autoimmune disorders were treated by the B cell-depleting antibody rituximab. Seven patients had systemic lupus erythematosus, 5 had polymyositis and there were single cases of mixed connective tissue disease, Takayasu's arteriitis, microscopic polyangiitis, Wegener's granulomatosis and cold agglutination disease. All patients were refractory to standard treatment regimens, many were in life-threatening conditions. As shown by CD19/CD20 FACS analysis, all patients were depleted of B cells after rituximab therapy. 16 patients achieved a partial or complete remission of the disease. Three serious infections probably caused by the therapy were observed. One patient experienced an anaphylactic infusion reaction, one patient developed a serious thrombocytopenia after the infusion. B cell depletion by the CD20 antibody rituximab is a highly effective therapeutic alternative for otherwise refractory autoimmune disorders.