Pharmacokinetic Interaction of Fimasartan, a New Angiotensin II Receptor Antagonist, With Amlodipine in Healthy Volunteers

AIM: Fimasartan (BR-A-657) is a new angiotensin II receptor antagonist used as antihypertensive agent. The objective of this study was to investigate the effect of the coadministration of fimasartan and amlodipine on the steady-state pharmacokinetics of each drug. METHODS: This study comprised 2 separate parts, A and B; each was a multiple-dose, open-label, 2-period crossover study in healthy male volunteers. In part A, 20 subjects were administered 120 mg of fimasartan alone in period I and fimasartan with 10 mg of amlodipine in period II. In part B, 14 subjects were administered amlodipine alone, followed by coadministration with fimasartan. Blood samples for pharmacokinetics were collected up to 24 hours after the last dosing. The pharmacokinetics of the coadministration of fimasartan and amlodipine were compared with that of each drug alone. RESULTS: The geometric mean ratio and 90% confidence intervals for C(max,ss) and area under the plasma concentration-time curve (AUC)(τ,ss) of fimasartan (with/without amlodipine) were 1.096 (0.746-1.610) and 1.163 (1.001-1.351), respectively. The geometric mean ratios (90% confidence interval) for C(max,ss) and AUC(τ,ss) of amlodipine (with/without fimasartan) after coadministration with fimasartan were 1.037 (0.969-1.110) and 0.975 (0.920-1.033), respectively. CONCLUSIONS: Coadministration of fimasartan and amlodipine did not result in clinically relevant changes in the systemic exposure of fimasartan or amlodipine.