Low-dose rituximab and alemtuzumab combination therapy for patients with steroid-refractory autoimmune cytopenias.

Treatment of autoimmune cytopenias remains unsatisfactory for patients refractory to first-line management. We evaluated the safety and efficacy of low-dose rituximab plus alemtuzumab in patients with steroid-refractory autoimmune hemolytic anemia and immune thrombocytopenic purpura. Nineteen of 21 included patients were assessable for response (11 with immune thrombocytopenic purpura, 8 with autoimmune hemolytic anemia). Treatment with 10 mg of alemtuzumab subcutaneously on days 1 to 3, plus 100 mg of rituximab intravenously weekly in 4 doses, was administered. The overall response rate was 100%, with complete response in 58%. The median response duration was 46 weeks (range, 16-89 weeks). Median follow-up was 70 weeks (range, 37-104 weeks). Most toxicity was grade 1 fever related to the first dose. Six patients developed infections. The combination of rituximab and alemtuzumab is feasible and has an acceptable safety profile and remarkable clinical activity in this group of patients. This study is registered at www.clinicaltrials.gov as #NCT00749112.