Mycophenolate mofetil (MMF) is more effective than azathioprine as maintenance therapy for patients with active lupus nephritis (LN) who responded to induction therapy, researchers reported.
In a 36-month randomized, double-blind study of 227 LN patients who met response criteria during a six-month induction trial, the researchers found that MMF significantly decreased the time to treatment failure, the primary outcome measure. The researchers defined treatment failure as death, end-stage renal disease, doubling of serum creatinine level, renal flare, or rescue therapy for LN. The overall observed rates of treatment failure were 16.4% among the 116 patients assigned to receive oral MMF and 32.4% among the 111 patients assigned to receive oral azathioprine. The difference translated into a 59% decreased risk of treatment failure for patients in the MMF group, according to findings published in The New England Journal of Medicine (2011;365:1886-1895). During the induction trial, subjects received either oral MMF or intravenous (IV) cyclophosphamide.
In addition, compared with azathioprine recipients, MMF-treated patients had a 50% decreased risk of renal flare and a 61% decreased risk of requiring rescue therapy.
The rates of serious adverse events (AEs) in the MMF and azathioprine groups were not significantly different (23.5% vs. 33.3%, respectively), but the rate of study withdrawal related to AEs was significantly higher with azathioprine than MMF (39.6% vs. 25.2%).
The authors, led by Neil Solomons, MD, of Vifor Pharma (formerly Aspreva Pharmaceuticals), which funded the study, concluded that MMF is superior to azathioprine in maintaining the renal response to treatment and in preventing relapse in patients with active LN who have had a clinical response to induction therapy with either MMF or IV cyclophosphamide.
In the study, the MMF dosage was 1 g twice daily and the azathioprine dosage was 2 mg/kg/day. The study protocol permitted the administration of up to 10 mg of prednisone per day or its equivalent.