Rituximab Is an Effective Therapy for Relapsed Thrombotic Thrombocytopenia Purpura

Abstract 5139

Rituximab, a monoclonal antibodies designed against a CD20 glycoprotein expressing lymphocytes. This drug has been implemented in the treatment of B Cell Lymphoproliferative disorders as well as other non-neoplastic diseases such as autoimmune disorders. Rituximab has produced response in auto-immune thrombocytopenia, auto-immune hemolytic anemia and refractory inhibitors to coagulation factors. The proposed mechanism is not yet well known but it is postulated that rituximab affect the balance between the cytotoxic T cells and B cells. This abstract present our experience with rituximab in the treatment of relapsed Thrombotic Thrombocytopenia Purpura and Hemolytic Uremic Syndrome TTP/HUS. a total of nine patients diagnosed with relapsed TTP/HUS with mean age of forty five years; range 27– 59. Eight black females and one white male with median time to relapse of 3 months (range from 3 weeks to two years). All patients were treated initialy with plasmapheresis and steroids and achieved complete response. All maintained on tapering course of steroids for ten weeks. Upon relapse patient were given rituximab 375 mg/M2 weekly; range 3–6 weeks. This was given after treatment with plasmaphersis/steroids; range 9–25 sessions. Peripheral blood smears, LDH, CBC, BUN and creatine were monitored. In most patients schistocytes were reduced to three per 5000 red cells.

In conclusion: Rituximab is an effective therapy in relapsedTTP/HUS, larger study needed to confirm efficacy. Rituximab to be considered in the first line therapy as well as maintenance is a valid point.