Comparison of two microemulsion of cyclosporine A in healthy volunteers.

This study evaluated the bioe- quivalence of a new Cyclosporine A microemul- sion formulation in comparison to the reference market standard. Twenty-four adult healthy volunteers were randomised to receive the two Cyclosporin A microemulsion formulations, at a dose of 2.5 mg/kg, according to a cross-over design. Blood samples were taken before drug administration and at 12 points within 24 hours. Cyclosporine A whole blood concentrations were determined by HPLC. The pharmacokinetic parameters AUC0-t and AUC0-∞ were calculated by the trapezoidal rule, Cmax and Tmax were obtained directly from blood data. AUCs and Cmax were tested for bioequiva- lence after log transformation of data, differences for Tmax were evaluated by the rank test of Wilcoxon for paired data. The 90% confidence in- terval ratio between tested/reference drug was 0.98 for AUC0-t, 0.96 for AUC0-∞ and 1.01 for Cmax. All of them were within the range of bioequivalence. Tmax was 1.60 ± 0.44 hours after test drug and 1.67 ± 0.48 after reference drug (p = 0.27, Wilcoxon test). According to these results the two Cyclosporine A microemulsion formulations can be consid- ered bioequivalent.