Objective To evaluate the bioequivalence of two formulations of minocycline hydrochloride capsules administered orally after fasting administration and fed administration.Methods An open-label,randomized,two-period,self-crossover design was employed to assess the bioequivalence study.Twenty-eight healthy subjects were enrolled in both fasting and fed groups,with each period involving a single administration of either the reference formulation or the test formulation of 50 mg,separated by a washout period of 7 days.The concentration of minocycline in human plasma was determined by HPLC-MS/MS and was used for calculating pharmacokinetic parameters and evaluating the bioequivalence of the test formulation and reference formulation.Results After oral administration of test and reference formulations of minocycline under fasting condition,the Cmax Values of minocycline were(541±137)ng·mL-1 for the test formulation and(558±140)ng·mL-1for the reference formulation.The AUC0-t values were(8 347±1 986)h·ng·mL-1 for the test and(8 205±1 790)h·ng·mL-1 for the reference.The t1/2 values were(18.2±2.84)h for the test and(18.0±3.05)h for the reference.After oral administration of the test and reference formulations of minocycline under fed condition,the Cmax values of minocycline were(349±72.1)ng·mL-1 for the test and(352±73.2)ng·mL-1for the reference.The AUC0-twere(6 428±1 077)h·ng·mL-1 for the test and(6 588±1 118)h·ng·mL-1 for the reference.The t1/2values were(18.5±3.10)h for the test and(18.4±3.21)h for the reference.Under fasting condition,the 90% confidence intervals for the geometric mean ratios of Cmax,AUC0-t,and AUC0-∞ between the test and reference formulations were(90.84%,101.46% ),(95.2%,102.8% ),and(95.31%,102.71% ),respectively.Under fed conditions,the 90% confidence intervals for the geometric mean ratios of Cmax,AUC0-t,and AUC0-∞ between the test formulation and the reference formulation were(94.71%,103.42% ),(95.40%,99.83% ),and(95.79%,100.02% ),respectively.Conclusions Bioequivalence of the two minocycline formulations was demonstrated after fasting administration and fed administration in a healthy Chinese population.

This paper describes the development and validation of a liquid chromatography-mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule (SR-test), as an instant-release tablet (IR-reference) and as the market leader sustained-release capsule (Rythmol, SR-reference) in male beagle dogs (n=8). In Study A comparing SR-test with IR-reference in a crossover design T max and t 1/2 of propafenone for SR-test were significantly higher than those for IR-reference while C max and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SR-test with SR-reference the observed C max and AUC of propafenone for SR-test (124.5±140.0 ng/mL and 612.0±699.2 ng·h/mL, respectively) were higher than for SR-reference (78.52±72.92 ng/mL and 423.6±431.6 ng·h/mL, respectively) although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation.