Effectiveness and safety of cyclophosphamide or tacrolimus therapy for idiopathic membranous nephropathy

Background: Guidelines recommend classical combined therapy of steroid and cyclophosphamide (CYC) for patients with idiopathic membranous nephropathy (IMN), while it is associated with severe adverse effects.

Aims: We conducted an observational and retrospective study to evaluate the effectiveness and safety of steroids plus tacrolimus (TAC) versus steroids plus CYC for IMN.

Methods: A total of 203 kidney-biopsy-proven IMN patients was enrolled in this study. One group (n = 142) received steroid combined with intravenous CYC (750 mg/m² body surface) and the other group (n = 61) received steroid combined with oral TAC (target blood concentration of 4-8 ng/mL). The primary outcomes were achievement of remission. The secondary end-points included incidence of adverse events, relapse rates, 24 h urinary protein (UP), serum albumin, serum creatinine and estimated glomerular filtration rate.

Results: Over the 18-month observation period, the study suggested that the remission rates at the first 3 months were significantly higher in TAC group than in CYC group (72.1% vs 54.9%, P < 0.05). Although the cumulative incidence of serious and non-serious adverse events was not different significantly between the two groups, the incidence after first 3 months was lower in TAC group. Levels of 24-h UP and serum albumin improved in the TAC group more than in the CYC group (P < 0.05) over the observed period.

Conclusions: Because of its short-term effectiveness and long-term safety profile, steroid plus TAC might be a better option for IMN.