Mycophenolate mofetil versus cyclophosphamide for inducing remission of ANCA vasculitis with moderate renal involvement.

OBJECTIVE We performed a single-centre non-blinded clinical trial to compare the clinical efficacies of mycophenolate mofetil (MMF) and intermittent cyclophosphamide (CTX) pulse therapy as induction treatments in patients with antineutrophil cytoplasmic antibody (ANCA) vasculitis (AAV) and moderate renal involvement. METHODS Patients with active AAV and serum creatinine <500 micromol/L received either MMF treatment (MMF group) or monthly CTX pulse therapy (CTX group) for 6 months. Disease activity was assessed using the Birmingham Vasculitis Activity Score (BVAS). The disease activity, remission rate, renal function and adverse reactions were compared between the two groups. RESULTS A total of 35 patients (15 male, 20 female: aged 49.1 +/- 12.2 years) were enrolled, with 18 in the MMF group and 17 in the CTX group. Of the 35 patients, 28 were MPO-ANCA positive and 2 were PR3-ANCA positive. Four patients were lost to follow-up in the CTX group. At Month 6, BVAS scores were much lower in the MMF group than in the CTX group (0.2 +/- 0.89 versus 2.6 +/- 1.7, P < 0.05). In the intent-to-treatment analysis, 14 of 18 patients (77.8%) treated with MMF and 8 of 17 patients receiving CTX (47.1%) had complete remission with an absolute difference of 30.7%. Eight of 18 patients (44.4%) in the MMF group and 2 of 17 patients (15.4%) in the CTX group recovered renal function. Serum ANCA decreased to normal in 41.7% of patients in the MMF group and in 16.7% in the CTX group. Side effects in the MMF group were pneumonia (1), herpes zoster (1) and gastrointestinal symptoms (2), and in the CTX group were leukocytopenia (1), gastrointestinal distress (4) and pneumonia (1). CONCLUSION Our study suggests that MMF effectively ameliorates disease activity and considerably improves renal function in patients with AAV. Further large-scale multicentre prospective randomized controlled trials will be needed to confirm these findings.