A COMPARATIVE ANALYSIS OF BIOEQUIVALENCE, CLINICAL EFFICACY AND SAFETY OF GENERIC VERSUS ORIGINAL CYCLOSPORINE AFTER KIDNEY TRANSPLANTATION

Abstract

The aim of the study was the evaluation of pharmacokinetic parameters and clinical efficacy of generic cyclosporine (Ecoral) and Sandimmune Neoral. Materials and methods’. The pharmacokinetic parameters of different cyclosporine formulations. In 197 kidney graft recipients 319 comprehensive pharmacokinetic studies were performed. In 42 patients received in consecutive order original and generic Cyclosporine in the same dosage the complete pharmacokinetic study was perforfomed. AUC calculations based on dosing interval concentration values were fulfilled using linear trapezoidal rule. To evaluate clinical efficacy 235 short pharmacokinetic studies with concentration examination at 0, 1, 2 and 3 hours after taking Cyclosporine (Co, C1 C2 and C3) were performed in patients treated with Neoral (n = 75) or generic cyclosporine (n = 160). Clinical efficacy of generic cyclosporine was estimated by the prevalence of allograft dysfunction and biopsy proved acute rejection episodes as well as by one-years graft survival and events-free survival. The graft survival rate was calculated by Kaplan–Meyer method. Results. At 100–200 ng/ml maintenance concentration (estimated by C0 concentration) pharmacokinetic parameters did not significantly differ according to Cyclosporine formulation in both complete or short pharmacokinetic studies: AUC-4265 vs. 4204 and 3834 vs. 3670 ng/ml/h respectively; (p > 0.05), Cmax (1036 vs 931 and 813 vs 741 ng/ml respectively; (p > 0.05). Allograft dysfunction occurred in 5% of patients subjected to Neoral immunosuppression and in 8% of Equoral recipients (p > 0.05). However biopsy-proven acute rejection as a cause of graft dysfunction was seen only in patients receiving Ecoral (7% vs 0; p < 0.05). One-years graft survival rate did not differ between groups (99% and 94% in generic CyA and Neoral respectively; p > 0.05), whereas events-free graft survival was significantly lower in patients, receiving generic CyA than in Neoral group (88 vs 94% respectively; p = 0,03). Conclusion. Pharmacokinetic studies have shown the absorption profile of generic formulations Equoral do not differ significantly from that of Neoral. Prospective pilot trial demonstrated no difference between one-year graft survival or graft dysfunction rate, but lower eventsfree one-year graft survival as well as the tendency to higher acute rejection rate in patients treated with generics in comparison with those receiving Neoral should be noted. This issue is to be studied further.

Keywords

• kidney transplantation
• pharmacokinetic study
• cyclosporine
• generic drugs
• bioequivalence