Bioequivalence study of Glimepiride

Aims and Objective; To compare the pharmacokinetics and bioavailability of Glybandyl (Glimepiride Tablets 4 mg) manufactured by Okaso Pharma Pvt,. Ltd, India with that of Amaryl (Glimepiride Tablets 4 mg) manufactured by Sanofi-Aventis, under fasting condition. Study Design: An Open label, randomised two-treatment, two way, two period, single dose crossover bio-equivaience study of Glybandyl (Glimepiride Tablets 4 mg) manufactured by Okaso Pharma Pvt,. Ltd, India Vs Amaryl 4mg (Glimepiride Tablets 4 mg) manufactured by Sanofi-Aventis in thirty two adult healthy male human subjects. The reference and the test formulations were administered on two days (Period 1 and Period 2) as a single oral dose after overnight fasting (at least 10 hrs) with 240 mL of 20% glucose solution. The wash out period was 7 days. Fasting blood samples were collected (0 hrs). After dosing venous blood samples were collected for a period of 36 hr. Plasma was separated immediately and stored in prelabelled polypropylene tubes at -50°C until the analysis. Plasma levels of Glimepiride at every time point for each volunteer was estimated and tabulated. The data were analyzed to calculate parameters of bioavailability like C_max, T_max, AUC, Kel and T1/2. Results: Mean Cmax was found to be 335.65 ± 13.71 ng/ml and 329.67 ± 16.77 ng/ml after 1.95 ± 0.07 hrs and 2.05 ± 0.07 hrs of test and reference preparation of Glimepiride 4 mg respectively. The AUCO-t for test preparation of Glimepiride 4 mg was found to be 1767.28 ± 77.19 ng.hr/ml and for reference 1759.25 ± 109.18 ng.hr/ml. The AUC0-∞ for test preparation was found to be 1978.93 ± 80.36 ng.hr/ml and that of reference 1954.43 ± 110.00 ng.hr/ml. The plasma elimination half-life of test drug and reference preparation was found to be 7.79 ± 0.28 hrs and 7.82 ± 0.25 hrs respectively. The elimination constant Kel (hr-1) of test drug and reference preparation was found to be 0.0913 ± 0.0029 hr-1 and 0.0906 ± 0.0029 hr-1 respectively. No significant variation was observed for all the pharmacokinetic parameters. No serious adverse events were observed. Conclusion: From the above results the study demonstrated that the test formulation is bioequivalent to the reference formulation in terms of its pharmacokinetic parameters.