Objective  There have been few studies on cyclosporine (CsA) monotherapy in adult minimal change nephrotic syndrome (MCNS). To delineate CsA therapy as new treatment options for MCNS, we conducted a prospective single-center study.
  Methods  We assessed the efficacy of 3 different regimens in 36 patients, consisting of 26 first attacks or 10 relapses, of adult-onset MCNS. In 12 patients, CsA alone was given orally at a dose of 2-3 mg/kg/d, and in 12 patients, CsA after intravenous pulse methylprednisolone therapy (CsA/PMT) was given at the same dose. CsA was given for 12 months, tapered slowly, then stopped. The other 12 patients were treated with oral prednisolone (PSL, 40-60 mg/d) alone for 4 to 6 weeks, followed by daily PSL, with slowly tapering doses.
  Results  Complete remission (CR) was obtained in 75% with CsA alone, 100% with CsA/PMT and 92% with PSL alone (p=0.0379). The days required for CR were shortest in the CsA/PMT group (40.9±35.5 days with CsA alone vs. 11.0±5.6 with CsA/PMT vs. 21.5±15.8 with PSL alone). The cumulative rates of CR were significantly different among the 3 groups (p<0.0001). The real numbers of the relapse were smallest in the CsA/PMT group, however, the cumulative rates of sustained remission among the 3 treatment arms were not statistically different. Renal function was well preserved with each treatment period. CsA-associated adverse effects were minimal but one patient developed new-onset hypertension and gingival hyperplasia. However, the adverse effects of PSL alone were serious in 3 cases: bleeding from gastric ulcer, diabetes mellitus, and aseptic necrosis. Many patients with PSL but few with CsA experienced cosmetic problems.
  Conclusions  CsA/PMT may be the most advantageous when the clinical efficacy of each treatment for MCNS is integrated.