Study of Mepolizumab-based Regimen Compared to Conventional Therapeutic Strategy in Patients With Eosinophilic Granulomatosis With Polyangiitis (E-merge)

Prior treatment

• Patients with EGPA who have already been treated with mepolizumab within the previous 12 months,
• Patients with contraindication to use mepolizumab, cyclophosphamide, mesna, azathioprine or maintenance therapy used for vasculitis,
• Patients included in other investigational therapeutic study within the previous 3 months,
• Patients unable to give written informed consent prior to participation in the study

Other illness

• 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 Association
• Patients with acute infections or chronic active infections (including HIV, HBV or HCV and checked in the last 12 months),
• Patients with hypersensitivity to a monoclonal antibody or biologic agent,
• Patients with other uncontrolled diseases, including drug or alcohol abuse, severe psychiatric diseases, that could interfere with participation in the trial according to the protocol,

Lab values

• Patients who have white blood cell count ≤4,000/mm3,
• Patients who have platelet count ≤100,000/mm3,
• Patients who have ALT or AST level greater that 3 times the upper limit of normal that cannot be attributed to underlying EGPA disease,

Age

• Patients with active cancer or recent cancer (\<5 years), except basocellular carcinoma and prostatic cancer of low activity controlled by hormonal treatment,

Other

• Patients with GPA, MPA, or other vasculitis, defined by the ACR criteria and/or the Chapel Hill Consensus Conference,
• Pregnant women and lactation. Patients with childbearing potential should have reliable contraception for the 12 months duration of the study,
• Patients suspected not to be observant to the proposed treatments,
• Patients under tutorship or curatorship and protected adults.

• Patients with a diagnosis of EGPA independently of ANCA status,
• Patients 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)
• Patients having given their written informed consent prior to participation in the study.
• Patients affiliated with social security or CMU (profit or being entitled)