Induction of remission in active anti-neutrophil cytoplasmic antibody-associated vasculitis with mycophenolate mofetil in patients who cannot be treated with cyclophosphamide

Background: Active anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is commonly treated with cyclophosphamide, a drug with serious side effects, and with corticosteroids. Objective: To determine the efficacy of a possible alternative drug for cyclophosphamide, oral mycophenolate mofetil (MMF) 1000 mg twice daily and oral prednisolone 1 mg/kg once daily as remission induction treatment. Methods: 32 consecutive patients with 34 episodes of active vasculitis who could not be treated with cyclophosphamide were diagnosed for a median (range) of 6.0 (0.3-22) years and experienced 4 (0-14) relapses prior to the current episode. Treatment response and relapse-free survival were analysed. Results: Complete remission (CR) was obtained in 25 (78%) patients, partial remission (PR) in 6 (19%), whereas 1 (3%) patient did not respond. 19 patients relapsed, 13 (52%) after CR, 14 (3-58) months after starting the treatment and 6 (100%) after PR, 6 (2-10) months after starting the treatment. The median relapse-free survival was 16 months, comparable with the interval between the previous relapse and the current MMF-treated relapse (17 (3-134) months). Relapse-free survival at 1, 3, and 5 years was 63%, 38% and 27%, respectively. Patients who had been treated successfully with cyclophosphamide before responded better (CR 84%, relapse 50%) than those who had not (CR 50%, relapse 100%). Minor gastrointestinal side effects and infections occurred frequently. MMF was prematurely discontinued due to adverse effects in two patients. Conclusion: MMF, in combination with prednisolone, can induce remission in patients with relapses of AAV intolerant to cyclophosphamide.