Efficacy of low-dose cyclosporin A in psoriasis: results of dose-finding studies.

The efficacy of cyclosporin A (CyA) in severe psoriasis was analysed in 457 adult patients included in five European multicentre dose-finding studies. Initial CyA doses were 1.25 mg/kg/day in 33 patients, 2.5-3 mg/kg/day in 285 and 5 mg/kg/day in 139. After 3 months of treatment, the reduction of the Psoriasis Area and Severity Index (PASI) score was 35 +/- 6% with 1.25 mg/kg/day of CyA, 57 +/- 2% with 2.5 mg or 3 mg/kg/day and 86 +/- 2% with 5 mg/kg/day (P less than 0.001). The rates of success, defined by a PASI score reduction greater than or equal to 75% or a score less than or equal to 8, were 24%, 52% and 88%, respectively. There were no differences in age, initial severity or duration of psoriasis. The improvement was maintained for 9 months or more in the majority of patients receiving continuous CyA therapy.