OBJECTIVETo evaluate the effectiveness, safety as well as the immunological change (peripheral T cell subpopulation) in patients with idiopathic thrombocytopenic purpura (ITP) treated with lower dose rituximab.

METHODSTwenty-six patients with refractory ITP which were unresponsive to or relapse after steriod and IVIG treatment were treated with rituximab (100 mg per week for four weeks) and intravenous immunoglobulin (IVIG) treatment. Whole blood cell count, serum concentrations of IgG, IgM and IgA, platelet associated (PA)-IgG, PAIgA and PAIgM, peripheral T cell subpopulations, and B cells of CD19(+)/CD20(+) were detected before and after rituximab therapy.

RESULTSComplete response (CR) was achieved in 6 patients (23.1%), response (R) in 10 (38.5%), and non-response (NR) in 10 (38.5%). One patient relapsed after R. The median follow-up time was 5.5 (0.8 - 8) months. The median response and CR time were 27 (1 - 104) and 41 (4 - 109) days, respectively. After the therapy, the serum concentrations of IgG, IgA, IgM, T cells of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD3(-)CD56(+), CD4(+)CD25(+) and CD4(+)CD25(+)FOXP3(+) were not changed, the number of CD4(+)CD25(+)FOXP3(-) T cells decreased (P < 0.05) and CD19(+)CD20(+) B cells significantly decreased (P < 0.01). PAIgG was lower after treatment compared with that before treatment (P < 0.05). There were no severe adverse effects during rituximab therapy.

CONCLUSIONLower dose rituximab may be an effective and safe modality for patients with ITP.