Azathioprine or Methotrexate Maintenance for ANCA-Associated Vasculitis

Current standard therapy for Wegener's granulomatosis and microscopic polyangiitis combines corticosteroids and cyclophosphamide to induce remission, followed by a less toxic immunosuppressant. This prospective, open-label, multicenter trial indicated that the safety and efficacy of azathioprine and methotrexate are similar for maintenance therapy after initial remission in these two conditions. This trial indicated that the safety and efficacy of azathioprine and methotrexate are similar for maintenance therapy after initial remission in Wegener's granulomatosis and microscopic polyangiitis. Combined corticosteroid and cyclophosphamide therapy remains the standard care for antineutrophil cytoplasmic antibody (ANCA)–associated vasculitides, despite the potential risk of adverse events, particularly with the long-term use of cyclophosphamide. 1 , 2 Moreover, even after induction with daily oral or pulse intravenous cyclophosphamide therapy, relapse rates remain as high as 15% at 12 months 3 and reach 38% at 30 months. 4 A decisive step in the approach to the treatment of Wegener's granulomatosis and microscopic polyangiitis was the development of a staged induction–maintenance strategy to reduce cumulative exposure to cyclophosphamide. This strategy uses cyclophosphamide to induce remission, followed by a less toxic immunosuppressant. . . .