Clinical Pharmacokinetic and Bioequivalence Studies of Two Brands of Cephradine in Healthy Korean Using HPLC Method

The goal of our research was to compare the pharmacokinetics and evaluate the bioequivalence of two brands of cephradine 500 mg capsules in 24 normal Korean volunteers. The plasma samples were acquired at 13 time points for 8 h after administration. The concentrations of cephradine in human plasma were measured by a high-performance liquid chromatography (HPLC). Isocratic mobile phase which consisted of acetonitrile, methanol, and 20 mM potassium phosphate (15/5/80, v/v/v, pH 3.48) was used to separate the analytical column cosmosil cholester (250 × 4.6 mm, 3 μm). Analytes were detected in ultraviolet (260 nm). The novel analytical method was described as simple sample preparation, a short retention time (less than 6 min) and making it suitable for use in clinical trials. Pharmacokinetic parameters, such as AUC0-t (20.54 vs 18.42 μg·h/mL), AUC0-infinity (21.22 vs 19.14 μg·h/mL), Cmax (12.69 vs 12.81 μg/mL), Tmax (1.22 vs 0.92 h), half-life (1.02 vs 1.13 h), extrapolation (3.22% vs 3.75%), and Ke (0.73 vs 0.69 h–1) were determined for the reference and test drugs in plasma. Pharmacokinetic parameters with a 90% confidence interval were 87% - 95% for AUC0-t and 91% - 115% for Cmax. They were satisfied within the bioequivalence range 80% - 125% of the KFDA guidelines. Therefore, our HPLC method was well applied in a bioequivalence and pharmacokinetic study of two formulations in normal subjects.