Successful repeat therapy with rituximab for relapsed thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disease that is treated successfully with therapeutic plasma exchange (TPE) and often with corticosteroids; however, almost one third of TTP patients have treatment failures that require either long-term TPEs or other adjunct therapies. Recent insights into the autoimmune-pathophysiology of this disease provide the rationale for immune-based therapies. Cumulative evidence suggests that rituximab, an anti-CD20 antibody that depletes B-cells temporarily, is an effective therapy in patients with refractory or relapsing TTP. We report here two patients with chronic relapsing TTP who were treated successfully with rituximab. However, both experienced TTP relapse following sustained and prolonged remissions for 21 and 37 months, respectively. They responded favorably with repeat therapy with rituximab. The benefits of rituximab treatment for refractory or relapsing TTP as well as in the prevention of recurrences are discussed.