Bioequivalence Study of Two Formulations of Mifepristone Tablets in Healthy Chinese Subjects Under Fasting Conditions

Abstract

AbstractA single‐dose, open‐label, randomized, two‐period crossover‐design study was conducted to evaluate the bioequivalence of the reference and test formulations of mifepristone tablets. Each subject was randomized at the beginning to receive a 25‐mg tablet of the test or the reference mifepristone under fasting conditions during the first period, then received the alternate formulation during the second period following a 2‐week washout period. A validated high performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) method was used to determine the plasma concentrations of mifepristone and its two metabolites (RU42633 and RU42698). Fifty‐two healthy subjects were enrolled in this trial, 50 of whom completed the study. The 90% confidence intervals for the log‐transformed Cmax, AUC0‐t, and AUC0‐∞ fell within the accepted 80%–125% range. Throughout the study period, a total of 58 treatment‐emergent adverse events were reported. No serious adverse event was observed. In conclusion, the test and reference mifepristone were bioequivalent and well tolerated under fasting conditions.