Idiopathic membranous nephropathy (IMN) is one of the most common forms of nephrotic syndrome (NS) in adults and is usually treated by corticosteroids in combination with cytotoxic drugs especially cyclophosphamide or cyclosporine. Tacrolimus, a new immunosuppressive agent, was proved to be effective in treating refractory NS. Whether it is effective in IMN has not been reported. We therefore undertook a multi-center, controlled study to investigate the efficacy and safety profile of tacrolimus compared with cyclophosphamide in the treatment of patients with idiopathic membranous nephropathy and nephrotic syndrome.

Idiopathic membranous nephropathy (IMN) is one of the most common forms of nephrotic syndrome (NS) in adults and is usually treated by corticosteroids in combination with cytotoxic drugs especially cyclophosphamide or cyclosporine. However, the effect was not satisfying and the side-effects of the above immunosuppressive agents were often a worrying problem. Tacrolimus, a new immunosuppressive agent, was proved to be effective in treating refractory NS especially FSGS. Whether it is effective in IMN has not been reported. We therefore undertook a multi-center, controlled study to investigate the efficacy and safety profile of tacrolimus compared with cyclophosphamide in the treatment of patients with idiopathic membranous nephropathy and nephrotic syndrome.

Inclusion Criteria:

• All patients were diagnosed as idiopathic membranous nephropathy according to renal histology, with nephrotic syndrome, serum creatinine less than 2.5mg/dL, 18~70 years old, signed the informed consent and willing to be followed up according to the protocol.

Exclusion Criteria:

• Patients who had received immunosuppressive therapy within the previous 3 months, complicated other severe renal diseases, serum creatinine higher than 2.5mg/dL, severe infection, diabetes mellitus, liver disease, pregnancy, lactating, and anticipated poor compliance with the protocol.