Bioequivalence Study of Atenolol Tablets in Healthy Chinese Subjects Under Fasting and Fed Conditions

Atenolol, a cardioselective β1-blocker, exhibits efficacy in treating cardiovascular diseases. We conducted a single-center, randomized, open, single-dose, 2-preparation, 2-cycle, 2-sequence, double-crossover trial with a 7-day washout period to investigate the pharmacokinetics, bioequivalence (BE), and safety of test and reference atenolol tablets (25 mg) in healthy Chinese volunteers. Forty-eight healthy participants were randomized into the fasting and fed arms. After administering a single oral dose of the test or reference formulation (25 mg), plasma atenolol concentrations were measured using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were obtained from concentration-time profiles. In total, 23 and 24 individuals were included in the fasting and fed arms, respectively. The mean concentration-time profiles for both formulations were similar, and C_max, AUC_0-t, and AUC_0-∞ were within the BE range of 80%-125%. Thirteen adverse events (AEs) were observed in 7 participants in the fasting arm; 1 withdrew from the trial early owing to an AE. In the fed arm, 20 AEs were observed in 8 participants, and none withdrew from the trial. All adverse reactions were grade I, with no serious AEs or deaths. Therefore, the 2 tablets are bioequivalent in healthy Chinese individuals under fasting and fed conditions, supporting their further clinical development.