Bioequivalence and Pharmacokinetics Study of Losartan Potassium Tablets in Healthy Volunteers by LC-MS/MS Method

OBJECTIVE To develope an LC-MS/MS method for the determination of losartan in human plasma,and to evaluate the pharmacokinetics and bioequivalence of losartan tablets in healthy volunteers.METHODS A single oral dose of reference and test tablets was given to 20 healthy male volunteers according to a randomized crossover design.Plasma concentrations were determined by LC-MS/MS after deproteinization by methanol.The pharmacokinetic parameters were calculated by DAS2.0.RESULTS The main pharmacokinetic parameters of losartan test and reference preparations were as follows: ρmax(222±131) and(226±166) μg·L-1,tmax(1.28±0.64) and(1.45±0.70) h,t1/2(1.91±0.32) and(1.90±0.37) h,AUC0-12 h(450±191) and(446±227) μg·h·L-1,respectively.The relative bioavailability of the test preparation was(104.0 ±14.3)%.CONCLUSION The LC-MS/MS method is proved to be accurate,sensitive and convenient;the test tablets are bioequivalent to the reference tablets.