Treatment of Refractory Chronic Immune Thrombocytopaenic Purpura (ITP) with Rituximab: Report of a Cases Series.

Purpose: To describe the response rates and time to treatment failure in patients with chronic refractory ITP treated with Rituximab.

Methods: Fourteen consecutive patients with chronic refractory ITP, who didn’t achieve a response to first- and second-line treatments (including splenectomy), were recruited between November 2001 and May 2004. Rituximab was administered at 375 mg/m² iv weekly’ 4 and all patients were pre-medicated with Diphenhydramine (30 mg single dose) and Hydrocortisone (100 mg IV single dose). The first response assessment was performed at week 4, using the following criteria: complete response, platelet count > 100 x 10⁹/L; partial response, platelet count > 50 x 10⁹/L; minimal response, platelet count persisted below 50 x 10⁹/L but without bleeding or need for platelet transfusion; and no response if the platelet count did not change, or the patients required platelet transfusion or remained symptomatic. The response was considered sustained if it persisted for at least 6 months.

Results: The age range was 17–70 years; the baseline platelet count range was 3–37 x 10⁹/L. Five patients achieved a complete response, four patients a partial response, four a minimal response and one no response. The time to response was from 4–32 weeks and 10 patients showed a sustained response. No patients with a response showed bleeding and no patients required the use of other drugs.

Conclusions: These results suggest that Rituximab should have a significant therapeutic effect and an acceptable safety profile in patients with refractory chronic ITP. However, there is a lack of randomized, prospective studies to demonstrate the therapeutic benefit of this treatment.