Bioequivalence and safety of entecavir tablets in healthy Chinese subjects

Objective To investigate the bioequivalence and safety of the generic drug entecavir versus the original drug entecavir tablets in healthy Chinese subjects. Methods A randomized,open,two-cycle,two-cross,fasting trial was designed and performed for 28 healthy subjects,and the subjects were given single oral administration of the test preparation or the reference preparation at a dose of 0. 5 mg in the two cycles,respectively. Liquid chromatography-tandem mass spectrometry was used to measure plasma concentration at 16 different time points within 72 hours after administration,and the main pharmacokinetic parameters Cmax,AUC0-t,and AUC0-∞were calculated to evaluate bioequivalence. WinNonlin software was used to calculate pharmacokinetic parameters and perform bioequivalence evaluation. Results After the oral administration of the test preparation or the reference preparation in the fasting state,the main geometric means( 90% confidence interval) of the main pharmacokinetic parameters Cmax,AUC0-t,and AUC0-∞were 98. 18%( 91. 36%-105. 50%),101. 97%( 98. 32%-105. 74%),and 103. 07%( 96. 30%-110. 32%),respectively,all of which were within the range of 80. 00%-125. 00%.After the pharmacokinetic parameters Cmax,AUC0-t,AUC0-∞were transformed by natural logarithm,the variance analysis was carried out. The P value test results showed that the difference between the dosing weeks( P < 0. 05),the dosing sequence and differences in formulation factors( P > 0. 05). Meet the criteria of bioequivalence. Conclusion The two preparations are bioequivalent and have good safety in healthy Chinese subjects.