AbstractThe incidence of type 2 diabetes is high, and the existing metformin hydrochloride (MH) tablets of 250 mg cannot meet the demands of the Chinese drug market. This study aimed to evaluate the bioequivalence and safety of generic formulations of MH tablets (test formulation [T], 250 mg/tablet) and innovative products (reference formulation [R], 250 mg/tablet) under fasting conditions. This was an open‐label, single‐dose, 2‐period, 2‐sequence crossover, single‐center, randomized phase I clinical trial. T and R were considered bioequivalent if the adjusted geometric mean ratios (GMRs) and 90% confidence intervals of the area under the curve (AUC) and maximum concentration (Cmax) were within the range of 0.8‐1.25. Thirty‐five participants completed the trial. The T/R adjusted GMRs (95.7% for Cmax, 98.7% for AUC0→t, 98.8% for AUC0→∞) were within the acceptable bioequivalence range of 80%‐125%. No serious adverse events or suspected or unexpected serious adverse reactions occurred during this trial. The study findings confirmed that generic MH is a well‐tolerated and bioequivalent alternative to innovative products under fasting conditions in healthy Chinese participants. (www.chinadrugtrials.org.cn; registration no. CTR20190356)