Success using tacrolimus in patients with proliferative and membranous lupus nephritis and refractory proteinuria

Standard treatment for class III, IV, and V lupus nephritis (LN) is a combination of oral corticosteroids and mycophenolate mofetil (MMF). There is an estimated failure rate of 16%. Several small studies have looked at the use of tacrolimus in class III, IV, and V LN, both as induction treatment and as maintenance in patients refractory to other treatments. The majority of these studies were conducted in Asian patients. We discuss a cohort of eight female patients of various ethnicities with biopsy proven LN. All patients were evaluated retrospectively. Six were started on tacrolimus after failing to respond to MMF and corticosteroids, and one was started on tacrolimus alone because treatment options were limited by pregnancy. Five were Caucasian, one African American, one Hispanic, and one Vietnamese. Mean tacrolimus dose was 3.3mg daily (range 2-5 mg) titrated to a mean level of 3-6 ng/dl (range 3-6.6 ng/dl) for a mean of duration of 16 months (range 2-54 months). Six patients experienced complete remission (proteinuria <0.33 g/day), and two patients had a partial remission (minimum of 50% reduction in baseline proteinuria). Albumin increased an average of 32%. Average C3/C4 levels were 64/15 mg/dL, respectively, prior to treatment, and 95/25 mg/dL following treatment. No treatment-limiting adverse effects were reported. Our case series supports the growing body of evidence that tacrolimus is an effective therapy in LN patients with refractory proteinuria. Further studies are required to establish the long-term safety and efficacy of tacrolimus.