Background and aims One phase III study has reported that Leflunomide(LEF) in combination with prednisone was effective in the induction therapy of proliferative lupus nephritis (LN). However, long-term data of LEF in the maintenance treatment of LN are lacking. The aim of this study was to investigate the long-term outcomes of LEF in the maintenance treatment of LN in an open-label extension of a prospective multi-centre observational study.

Methods 70 patients were enrolled into LEF induction group with a loading dose of 50 mg/day for 3 days, followed by 30 mg/day for six months. The partial and complete remission rate was 52% and 21%. Among them, 15 patients voluntarily entered an open labelled extension study. Data for survival and kidney function were prospectively collected during a 12 year period for the 15 patients who were maintained on 20 mg/day LEF.

Results 15 patients (mean age 40.2±7.4 years; 86.6% female) were treated with LEF for >12 months,the mean duration of LEF treatment was 11.8 years. During a median follow-up period of 12.3 years, 1 patient died from sepsis, 4 patients developed renal flare. The 12 year cumulative survival rates for the composite end point of death and chronic renal failure were 93.3% and 100%, respectively. At the final follow-up, the complete remission rate in the remaining patients was 71.43%, the partial remission rate was 28.57%,the mean proteinuria leval was 0.33g/day(range 0.07–1.62 g/day), and the mean serum creatinine leval was 62.3 umol/L.

Conclusions Our data suggest that a remission-inducing regimen of LEF followed by maintenance therapy with LEF resulted in good long-term patient survival and renal preservation.