Rituximab in Eosinophilic Granulomatosis With Polyangiitis

Inclusion Criteria: * Patients with a diagnosis of EGPA independently of ANCA status, * Patient aged of 18 years or older, * Patients with newly-diagnosed disease or relapsing disease at the time of screening, with an active disease defined as a Birmingham Vasculitis Activity Score (BVAS) ≥3, * Patients within the first 21 days following initiation/increase of corticosteroids at a dose ≤ 1 mg/kg/day (pulses of methylprednisolone before oral corticosteroid therapy are authorized) , * Patient able to give written informed consent prior to participation in the study. Exclusion Criteria: * Patients with GPA, MPA, or other vasculitides, defined by the ACR criteria and/or the Chapel Hill Consensus Conference, * Patients with vasculitis in remission of the disease defined as a BVAS \<3, * Patients with severe cardiac failure defined as class IV in New York Heart Assocation * Patients with acute infections or chronic active infections (including HIV, HBV or HCV), * Patients with active cancer or recent cancer (\<5 years), except basocellular carcinoma and prostatic cancer of low activity controlled by hormonal treatment, * Pregnant women and lactation. Patients with childbearing potential should have reliable contraception for the 12 months duration of the study, * Patients with EGPA who have already been treated with rituximab within the previous 12 months, * Patients with hypersensitivity to a monoclonal antibody or biologic agent, * Patients with contraindication to use rituxim…