ofatumumab for acute treatment and prophylaxis of a patient with multiple relapses of acquired thrombotic thrombocytopenic purpura

Acquired thrombotic thrombocytopenic purpura (ttp) is an autoimmune disorder resulting in potentially life-threating systemic thrombotic microangiopathy due to production of antibodies directed against the von willebrand factor-cleaving protease adamts13. typically managed with plasma exchange, glucocorticoids, and the first-generation anti-cd20 monoclonal antibody rituximab, patients with multiple relapses or refractory disease present unique management challenges. we describe a case of a young woman with multiple relapses of ttp despite standard therapy who was treated with ofatumumab, a second-generation anti-cd20 monoclonal antibody, after developing a severe hypersensitivity reaction to rituximab precluding its use. ofatumumab was effective for the treatment of an acute relapse of ttp in combination with plasmapheresis and as a single-agent for prophylaxis. the patient has had no evidence of relapse 2 years after completion of acute treatment and 1 year after completing prophylactic therapy. hypersensitivity to ofatumumab did not develop.