Objective: To compare the efficacy (maintenance of remission), safety and tolerability of cyclosporin (CsA) with those of cyclophosphamide in patients with steroid-dependent or frequently relapsing nephrotic syndrome (NS).
Design: Open, prospective, randomized, multicentre, controlled study for parallel groups, stratified for adults and children. The setting was in nephrological departments in Italy.
Subjects and interventions: Seventy-three patients with steroid-sensitive idiopathic NS admitted to the study were randomly assigned to cyclophosphamide (2.5 mg/kg/day) for 8 weeks or CsA (5 mg/kg/day in adults, 6 mg/kg/day in children) for 9 months, tapered off by 25% every month until complete discontinuation at month 12. Seven patients lost to follow up were not considered in the analysis. The remaining 66 patients were followed up for 3-24 months after randomization.
Main outcome measures: Relapse-free survival; number of N.S. relapses/patient/year; cumulative dose of prednisone/patient; laboratory investigations (kidney and liver functions, haematological parameters); incidence of adverse events.
Results: At month 9, 26 of 35 CsA-treated patients were still in complete remission and a further five patients were in partial remission; 18 of 28 cyclophosphamide-treated patients were in complete remission, and one in partial remission (P = NS). No difference between adults and children was seen with either treatment. The risk of relapse was similar between frequent relapsers (19 of 22) and steroid-dependent patients (8 of 14) given CsA, and those given cyclophosphamide (5 of 15 and 6 of 15). The mean number of relapses per year and the mean dose of prednisone per year were significantly less (P < 0.001) in both groups for the experimental year than for the year before randomization. At 2 years, 25% of the patients given CsA (50% adults and 20% children) and 63% of those given cyclophosphamide (40% adults and 68% children) had not had any relapse of NS. Tolerance to the two drugs was generally good. The CsA-related side-effects were mild and disappeared after drug discontinuation.
Conclusions: This study shows that both treatments are effective and well tolerated; more patients given cyclophosphamide had stable remissions.