Long-term outcome of mycophenolate mofetil treatment for patients with microscopic polyangiitis: an observational study in Chinese patients

This study aimed to retrospectively analyze the long-term outcome of mycophenolate mofetil (MMF) therapy for microscopic polyangiitis (MPA) with mild to moderate renal involvement in Chinese patients. Thirty-four MPA patients (24 females, 10 males, aged 44.7 +/- 17 years, BVAS score 13.8 +/- 3.2, SCr 2.2 +/- 1.1 mg/dl) with SCr < 5 mg/dl and who received glucocorticoids plus MMF therapy for inducing and maintaining remission were included in this study. The remission and relapse rates, patient and renal survival rates and adverse events were retrospectively analyzed. We found that 31 (91.2 %) of 34 patients achieved remission and were continuously treated with glucocorticoids plus MMF for maintaining remission. The median duration of MMF treatment was 24 months (IQR 15-53 months) and follow-up time was 86 months (IQR 29-124 months). During the follow-up, 7 (22.6 %) patients relapsed, one patient died, and one patient progressed into end-stage renal disease. The 5-year patient and renal survival rates were 92.8 and 95.2 %, respectively. 11 (32.4 %) patients suffered 16 adverse events, 13 of which were pulmonary infection. In conclusion, glucocorticoids plus MMF regimen as induction and maintenance therapy could achieve high remission rate and good long-term renal survival in MPA patients with mild to moderate renal involvement. Prospective controlled trials with a large sample size are needed to confirm the efficacy of MMF in this population.