Pharmacokinetic and Bioequivalence Evaluation of Two Repaglinide Tablets Under Fasting and Fed Conditions in Healthy Chinese Volunteers

Repaglinide, an insulin secretagogue that predominantly lowers postprandial glucose, is approved for patients with type 2 diabetes inadequately controlled by diet, weight loss, and exercise. This study used a single-center, randomized, open-label, two-formulation, single-dose, four-period, fully replicated, crossover design to evaluate the pharmacokinetics, bioequivalence, and safety of generic repaglinide tablets (1 mg) versus the innovator product in healthy Chinese subjects under fasting and fed conditions. Blood samples were assayed by validated liquid chromatography-tandem mass spectrometry. After natural logarithmic transformation of pharmacokinetic parameters (C_max, AUC_0-t, and AUC_0-∞), the bioequivalence of the test formulation and the reference formulation was evaluated using two one-sided t-tests and the 90% confidence intervals (CIs) method. The least-squares geometric mean ratios (test/reference) and 90% CIs for C_max, AUC_0-t, and AUC_0-∞ all fell within the conventional bioequivalence ranges of 0.80-1.25. Both formulations were well tolerated, with no serious adverse events reported, and the food effect on repaglinide pharmacokinetics is further discussed. In summary, test and reference repaglinide tablets are bioequivalent and demonstrate similar pharmacokinetic characteristics and safety in healthy Chinese volunteers under both fasting and fed states.