Abstract

To assess whether chlorambucil or cyclophosphamide may have a better therapeutic index in patients with idiopathic membranous nephropathy, we compared two regimens based on a 6-mo treatment, alternating every other month methylprednisolone with chlorambucil or methylprednisolone with cyclophosphamide. Patients with biopsy-proven membranous nephropathy and with a nephrotic syndrome were randomized to be given methylprednisolone (1 g intravenously for 3 consecutive days followed by oral methylprednisolone, 0.4 mg/kg per d for 27 d) alternated every other month either with chlorambucil (0.2 mg/kg per d for 30 d) or cyclophosphamide (2.5 mg/kg per d for 30 d). The whole treatment lasted 6 mo; 3 mo with corticosteroids and 3 mo with one cytotoxic drug. Among 87 patients followed for at least 1 yr, 36 of 44 (82%; 95% confidence interval [CI], 67.3 to 91.8%) assigned to methylprednisolone and chlorambucil entered complete or partial remission of the nephrotic syndrome, versus 40 of 43 (93%; 95% CI, 80.9 to 98.5%) assigned to methylprednisolone and cyclophosphamide (P = 0.116). Of patients who attained remission of the nephrotic syndrome, 11 of 36 in the chlorambucil group (30.5%) and 10 of 40 in the cyclophosphamide group (25%) had a relapse of the nephrotic syndrome between 6 and 30 mo. The reciprocal of plasma creatinine improved in the cohort groups followed for 1 yr for both treatment groups (P < 0.01) and remained unchanged when compared with basal values in the cohort groups followed for 2 and 3 yr. Six patients in the chlorambucil group and two in the cyclophosphamide group did not complete the treatment because of side effects. Four patients in the chlorambucil group but none in the cyclophosphamide group suffered from herpes zoster. One patient per group developed cancer. It is concluded that in nephrotic patients with idiopathic membranous nephropathy both treatments may be effective in favoring remission and in preserving renal function for at least 3 yr.