[Clinical therapeutic efficacy of rituximab for relapsed and refractory idiopathic thrombocytopenic purpura].

The aim of this study was to evaluate the effect of rituximab treatments for refractory and relapsed idiopathic thrombocytopenic purpura (ITP). 18 patients with refractory and relapsed ITP who received 22 courses of rituximab treatments from January 2007 to December 2010 were analyzed retrospectively. Rituximab was given at a dose of 375 mg/m(2) intravenously weekly for a continuous 4 weeks. The results indicated that responses were achieved in 15 of 22 (68%) courses, out of which complete responses were achieved in 10 of 22 (45%) courses, partial and minimal responses were achieved in 5 of 22 (23%) courses, and no responses were achieved in 7 of 22 (32%) courses. The median time of response was 3 weeks (1 - 17 weeks) from the start of treatment and median duration of response was 13 weeks (1 week - 42 months). The responses were mostly short-sustained and follow-up median time was 20 months (1 - 52 months). The responses of 8 patients (36%) sustained for over 6 months, 6 patients (27%) sustained for over 1 year, and 4 patients also showed sustained response at last visit of follow-up. Previous splenectomy resulted in a poor response (P = 0.037). Patients who failed in rituximab treatment and prior received multiple treatments including splenectomy, had a poor response to further therapies. It is concluded that rituximab is well tolerated by patients and is useful in some patients with relapsed and refractory ITP, however, only about 20% patients can achieve sustained remissions. The patients who failed in rituximab treatment has a poor response to further treatment.