Pharmacokinetics of Cyclosporine from Conventional and New Microemulsion Formulations in Healthy Volunteers

The bioavailability of two microemulsion formulations of cyclosporine (Drug A, cyclosporine Neoral, Sandoz Pharma Ltd., Switzerland and Drug B, cyclosporine Bioral, Panacea Biotec Ltd., India) was compared in 12 healthy volunteers in a randomized, double blind, cross over manner. Blood cyclosporine levels were analyzed by high performance liquid chromatography. The peak concentration was 1600.63 ± 70.01 ng/ml with drug A and 1571.70 ± 65.40 ng/ml with drug B. The area under the concentration time curve (AUC 0 ∝) was 15321.69 ± 982.7 ng/ml and 13727.11 ± 722.90 ng/ml with drug A and drug B, respectively. These differences were statistically insignificant (p > 0.05). The other pharniacokinetic parameters of both the preparations were comparable suggesting that both the preparations are bioequivalent. Also, the pharmacokinetics of cyclosporine from the new microemulsion was compared with the conventional formulation in normal healthy volunteers done in an earlier study. The Cmax was greater with microemulsion (1571.70 ± 65.40) than conventional formulation (950.61 ± 83.99) and the variation in Cmax between groups and within groups with microemulsion was 14.1% and 14.79%, respectively as compared to 31.75% and 31.95% with conventional formulation. The time to achieve Cmax (tmax) was significantly shorter for microemulsion as compared to conventional formulation showing better bioavaitability from microemulsion. (JAPI 1998; 46 : 860-3) (TOP^)