Anti-CD20 Monoclonal Antibody in the Treatment of Refractory Autoimmune Cytopenias in Adults.

Anti-CD20 monoclonal antibody (rituximab) has been used in autoimmune cytopenia with variable success.We report 13 patients with chronic refractory autoimmune hemolytic anemia (AIHA) and idiopathic thrombocytopenic purpura (ITP) who each received 4 cycles of rituximab 375mg/m² weekly. All 8 AIHA patients (6 idiopathic,2 secondary to a lymphoproliferative disorder, 5 splenectomised) had warm antibody type. Response was seen in 4(50%) of 8 patients (3 CR,1PR) and 3 patients remain in CR at 5,7,14 months post-therapy. Median time to maximum response (TMR) in responders was 9 weeks(range 6 – 18 weeks). In 5 ITP patients (4 splenectomised), 4(80%) responded (3CR) and one continues in CR 50 weeks after completion of rituximab treatment Median time to maximum response was 4 weeks (range 4 – 12 weeks). No pre-treatment clinical or laboratory parameters that predict response could be identifird in the AIHA or ITP groups.Our data indicate that rituximab is a relatively safe and effective treatment option in patients with refractory autoimmune hemolytic anemia and thrombocytopenia.

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