Bioequivalence of losartan potassium tablets in Chinese healthy volunteers

Objective To evaluate the bioequivalence of the two losartan potassium tablets(angiotensin Ⅱ receptor) in Chinese healthy volunteers.Methods A single oral dose 50 mg of tested and referened losartan potassium tablets were given to 24 volunteers according to an open randomized crossover design.The concentrations of losartan and its active metabolite E3174 in plasma were determined by LC-MS/MS simultaneously.The pharmacokinetic parameters were caculated and the bioequivalence was compared by BAPP 2.0 program.Results The main pharmacokinetic parameters of losartan of the test and reference preparations were as follows: Cmax were(253.10±155.43),(232.37±136.66) ng·mL-1;Tmax were(1.09±0.70),(1.30±0.80) h;t1/2 were(1.93±0.32),(1.98±0.53) h;AUC0-12 were(454.19±166.61),(414.97±152.22) ng·h·mL-1,the confidence interval 99.4%-118.6%.The relative bioavailability of losartan of test preparations was(112.0±29.9)%.The main pharmacokinetic parameters of E3174 of the test and reference preparations were as follows:Cmax were(447.45±132.66),(430.81±135.78) ng·mL-1;Tmax were(3.56±1.14),(3.77±1.14) h;t1/2 were(4.55±0.61),(4.67±0.68) h;AUC0-36 were(3522.17±11162.22),(3307.16±1078.13) ng·h·mL-1,the confidence interval was 100.5%-111.8%.The relative bioavailability of E3174 of test preparations was(107.2±16.8)%.The main pharmacokinetic parameters of losartan and E3174 showed no statistically significant difference between two preparations.Conclusion The two preparations were bioequivalent.