OBJECTIVETo evaluate the efficacy and safety of lower doses rituximab(375 mg/m²×1) in primary children immune thrombocytopenia (ITP).

METHODSFifty children [23 male and 27 female, the median age was 9.5 years (rage 3.5-17.0 years)]with persistent and chronic ITP were treated with lower doses rituximab from January 2009 to January 2013 in our hospital. Efficacy and side effects of lower doses rituximab was studied, and factors related to the outcomes were analyzed.

RESULTSAmong fifty patients, 17/50(34%) achieved a complete response (CR) and 15/50 (30%) patients got response (R). Patients with CR continued to maintain a platelet count above 50×10⁹/L at a median 12.3 (6-40) months. Patents with R continued to maintain a platelet count above 30×10⁹/L at a median 6 (2-12) months. The overall response (OR) in 3 and 6 months were 58% (29/50), 64% (32/50) respectively. Six patients have mild and transient side effects, including urticarial rash and fever, which were promptly resolved with appropriate therapy. Sex, age at diagnosis, interval from diagnosis to initial treatment with rituximab, platelet count at treatment and CD19+B cell count did not influence the overall response and complete response (P>0.05). Patients with anti-GPIIb/IIIa autoantibody had a better OR (P<0.05).

CONCLUSIONChildren with persistent and chronic ITP treated by lower doses rituximab had better therapeutic effects. Patients with anti-GPIIb/IIIa autoantibody had better response. Rituximab was well tolerated and no related serious side effects were recorded in the study.