Studies on Bioequivalence of Mifepristone Tablets in Healthy Volunteers

Objective:To investigate the bioequivalence of two minefristone preparations in healthy volunteers.Methods:A total of 24 healthy female volunteers were enrolled in arandomized crossover study in which the subjects were randomly assigned to receive single dose of 50 mg minefristone tablet(test preparation)or minefristone tablet (reference preparation).Plasma concentrations of minefristone were determined by LC-MS-MS method.The pharmaco- kinetic parameters and bioequivalence were calculated with BAPP 2.2 and DAS 2.1 software.Results: The main pharmacokinetic parameters of test and reference preparations were as follows:Cmax(1 405.70±380.50) and (1 263.80±258.80) ng?h?mL-1,tmax (0.70±0.30) and (0.60±0.30) h,t1/2β(31.70±7.80) and (28.70±9.40) h,AUC0~120 (17 821.50± 4 316.90) and (17 612.90±6 667.40) ng?h?mL-1,AUC0~∞(19 286.40±5 024.80) and (19 053.40±7 142.30) ng?h?mL-1.The relative bioavailability of minefristone tablets was114.60%.The 90% confidential intervals(CI)of AUC0~96 of the test preparation was among the bioequivalent threshold compared with that of the reference preparation.Conclusion: Test and reference preparations of mifepristone are bioequivalent.