The investigators are undertaking a parallel group, multicentre, randomised controlled trial of 240 refractory ITP adult patients from 14 medical centers in China. One part of the participants are randomly selected to receive recombinant human thrombopoietin (given subcutaneously at a dose of 300 Units/kg for 14 consecutive days,following with a flexible dosage depending on platelet count until the 29th day), combining with rituximab (given intravenously at a dose of 100 mg weekly for 4 weeks, i.e. Day 1, 8, 15, 22; the others are selected to receive low-dose of rituximab treatment (given intravenously at a dose of 100 mg weekly, i.e. Day 1, 8, 15, 22). Platelet count, bleeding and other symptoms were evaluated before and after treatment. Adverse events are also recorded throughout the study. In order to report the efficacy and safety of the combination therapy compared to conventional rituximab therapy for the treatment of adults with refractory ITP.