TTP is a potentially fatal disease that responds to plasmapheresis 90% of the time. Therapeutic plasma exchange (TPE) replaces the missing protease and removes the circulating inhibitor. However, a substantial fraction of idiopathic TTP cases (10%-20%) might not respond to TPE alone, and, therefore, interest has been gathering around the use of the novel immunosuppressive anti-B-cell antibody, rituximab. A growing number of case reports have demonstrated intriguing successes in treating refractory autoimmune TTP with the new immunomodulator rituximab.Some cases include immunospuressive therapy or plasmapheresis in combination with Rituxan.
Despite this exciting new treatment modality, the fact remains that there have not yet been any prospective or comparative studies. Other options for refractory TTP include chemotherapy, more frequent plasmapheresis, splenectomy, immunosupression. Without such studies, Rituxan must be considered investigational under most plans’ definitions.
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