An Assessment of Pharmacokinetic Interaction Between Lobeglitazone and Sitagliptin After Multiple Oral Administrations in Healthy Men

Purpose: Patients with type 2 diabetes mellitus require strict blood glucose control, and combination therapy with a thiazolidinedione and dipeptidyl peptidase-4 inhibitors, such as lobeglitazone and sitagliptin, is one of the recommended treatments. The objective of this study was to investigate a possible pharmacokinetic interaction between lobeglitazone and sitagliptin after multiple oral administrations in healthy Korean men. Methods: Two randomized, open-label, multipledose, 2-way crossover studies were conducted simultaneously in healthy men. In study 1, men were randomly assigned to 1 of 2 sequences, and 1 of the following treatments was administered in each period: 1 tablet of lobeglitazone sulfate (0.5 mg) once daily for 5 days and or 1 tablet each of lobeglitazone sulfate (0.5 mg) and sitagliptin (100 mg) once daily for 5 days. In study 2, men were also randomly assigned to 1 of 2 sequences and the treatments were as follows: 1 tablet of sitagliptin (100 mg) once daily for 5 days or 1 tablet each of sitagliptin (100 mg) and lobeglitazone sulfate (0.5 mg) once daily for 5 days. Serial blood samples were collected up to 48 h after dosing on the fifth day. Plasma drug concentrations were measured by LC-MS/MS. Pharmacokinetic parameters, including C-max,C-ss and AUC(0-tau) , were determined by noncompartmental analysis. The geometric least-square mean (GLSM) ratios and associated 90% CIs of log-transformed C-max,C-ss and AUC(0-tau) for separate or coadministration were calculated to evaluate pharmacokinetic interactions. Findings: Nineteen men from study 1 and 17 from study 2 completed the pharmacokinetic sampling and were included in the analyses. The GLSM ratios of C-max,C-ss and AUC(0-tau) , were 0.9494 (95% CI, 0.8798-1.0243) and 1.0106 (95% CI, 0.9119-1.1198) for lobeglitazone (from study 1) and 1.1694 (95% CI, 1.0740-1.2732) and 1.0037 (95% CI, 0.9715-1.0369) for sitagliptin (from study 2), respectively. (C) 2020 Elsevier Inc.