Investigate the Relationship Between CYP2C19 Genetic Polymorphisms and Pharmacokinetics of Glipizide in Healthy Chinese Subjects

Blood samples were obtained from 127 unrelated healthy male Chinese subjects in Gansu Province. After genotyping, 14 subjects (age, 19-26; weight, 59.5-70.0 kg) were enrolled in the study. They were divided into two groups, EMs homo and PMs group. There were no significant differences in age or body weight seen in the two groups.

Each subject received 5 mg glipizide extended release tablet once daily for 7 days. For the first 6 days, glipizide was administered just after a standard breakfast. On day 7, after an overnight fast, each subject received a glipizide extended released tablet (Glucotrol XL, Pfizer, USA) with 100 mL water. Standard meals were given in 4 h and 10 h after dosing. Venous blood samples were collected immediately before and at 2, 4, 6, 8, 10, 12, 14, 16, 20, 24, 36, and 48 h after dosing. Blood samples, collected in EDTA tubes, were centrifuged (2500 g) immediately for 10 min and plasma samples separated were stored at -80ºC until assay.

For safety, blood glucose levels were determined directly by use of a Glucose Meter (Accu-Chek, Roche, Germany) at 0, 2, 4, 6, 8, 10, 12, 14, 16, 20and 24 h after last dosing (on day 7).