Jornal de Bioequivalência e Biodisponibilidade

Abstrato

Bioequivalence Study of Entecavir 0.5 mg Tablets in Healthy Thai Volunteers Under Fasting Conditions

Vipada Khaowroongrueng, Charinthon Seeduang, Suchada Rakphung, Mariam Duereh, Lalinthip Saeaue, Busarat Karachot, Isariya Techatanawat, Porranee Puranajoti, Praphassorn Surawattanawan

Entecavir is a nucleoside polymerase inhibitor indicated for chronic hepatitis B infection in order to minimize the development of serious consequences. The Government Pharmaceutical Organization (GPO), Thailand has developed HEPA-EN^®, entecavir 0.5 mg tablets as a generic substitute for the corresponding innovator product, Baraclude^® (Bristol-Myers Squibb Company, USA) to enhance patient adherence to continuous treatment. The bioequivalence study was conducted under fasting conditions using a randomized-sequence, open-label, 2-period crossover design. The plasma samples were collected for 72 hours in both study periods and analyzed using a validated liquid chromatography tandem mass spectrometry method. The 90% CIs of the geometric least squares mean ratio between the formulations of log-transformed AUC_^0-72h and C_max were 95.82-107.00% and 95.40-122.32%, respectively which were within the acceptance range for bioequivalence of 80.00-125.00%. The analysis of variance did not show any significant difference between the two formulations. Wilcoxon signed-rank test showed no significant difference in median t_max between two formulations. It was concluded that two entecavir 0.5 mg tablet formulations were bioequivalent based on insignificant difference in terms of rate and extent of absorption describing by peak drug concentration (C_max) and area under concentration-time curve (AUC_0-72h ).