The ITP-RITUX Cohort: An Observational Study on Rituximab Off-label Use for Immune ThrombocytoPenia.

Rituximab (RTX) is used in the treatment of malignant non-Hodgkin's indication for which it has been authorized since 1997 and why it is considered effective and well tolerated. Rituximab is also effective and well tolerated in combination with methotrexate in severe rheumatoid arthritis (RA) refractory to anti-TNF. To date, the RA is the only autoimmune disease in which rituximab has proven efficacy in randomized trials and has obtained authorization in this indication. There are also data from the literature, for the benefit of rituximab in other autoimmune diseases like Lupus, cryoglobulinemia associated to Hepatitis C or Sjogren's disease.

Immune Thrombocytopenia (ITP) is an autoimmune disease in which there is thrombocytopenia due in part to destruction of platelets by autoantibodies. In adults, the disease is most often chronic and in the most severe forms, the treatment of choice is splenectomy. Rituximab was suggested during chronic ITP when used with 4 weekly infusions of 375 mg/m2, 60% of patients achieve an immediate response and 30 to 40% a prolonged response. These encouraging results and the apparent good tolerance advocate for using rituximab as first-line treatment for patients refractory to splenectomy. In France, Afssaps - French Health Products Safety Agency has recently issued a temporary protocol processing to authorize rituximab in this indication. Nevertheless, many questions remain unresolved, including the tolerance of long-term treatment and the risk of late relapse in responders. This justifies the creation of this register, whose establishment is recommended by Afssaps - French Health Products Safety Agency.