Efficacy of rituximab in primary immune thrombocytopenia: an analysis of adult pretreated patients from everyday hematological practice.

Although rituximab has seen increasing use in the treatment of immune thrombocytopenia (ITP) for many years, its therapeutic role in this disease remains unclear. We retrospectively analyzed data of all patients with ITP treated with rituximab (375 mg/m(2) once weekly for four consecutive weeks) and consecutively entered the findings into the databases of six large academic centers in the Czech Republic. A total of 114 patients were included in the analysis. All of the patients received rituximab as a second or additional line of therapy. The overall response rate (ORR) after rituximab therapy was 72 % [48 % complete response (CR), 24 % partial response (PR)] at month 6, and 69 % (45 % CR, 24 % PR) at month 12. For the group of patients with newly diagnosed (acute) ITP, the results of treatment were significantly better than for the group of patients with persistent or chronic ITP; nonetheless, this group of patients was far too small (n = 18) for our findings to be generalized. Multivariate analysis revealed that the ORR was significantly influenced primarily by the number of therapies prior to rituximab (the more previous therapies, the worse treatment response). The results of our analysis "from everyday hematological practice" confirm the high efficiency of rituximab treatment in pretreated adult patients with ITP.