Background and objective: Valsartan, an angiotensin receptor blocker, is often used with calcium channel blockers (CCBs) such as amlodipine to control hypertension. Recently, the fixed-dose combination (FDC) of amlodipine 10 mg/valsartan 160 mg (Exforge) was approved. Amlodipine is a racemic mixture of CCB; S-amlodipine has higher activity than R-form. Therefore, AGSAV301, the FDC of S-amlodipine 5 mg/valsartan 160 mg was recently developed. The objective of this study was to compare the pharmacokinetic (PK) characteristics of S-amlodipine and valsartan when administered as one tablet each of Exforge and AGSAV301 to healthy male subjects.
Methods: This was a single-dose, randomized, open-label, two-way, two-period crossover study. Each subject received a single dose of AGSAV301 and Exforge, separated by a 3-week washout period. Plasma samples for the PK analysis of valsartan and S-amlodipine were collected at predose (0) and 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 16, 24, 36, 48, 72, 96, 120, and 168 h after administration. Tolerability was also evaluated.
Results: A total of 29 subjects were enrolled; 24 completed this study. The S-amlodipine maximum plasma concentration (C max) geometric mean ratio (GMR) between AGSAV301 and Exforge was 0.951 (90 % CI 0.983-1.014), and area under the concentration-time curve from time 0 to last measured time point (AUClast) was 0.917 (90 % CI 0.861-0.976). The GMR of valsartan C max was 0.994 (90 % CI 0.918-1.076), and the AUClast was 0.927 (90 % CI 0.821-1.047). All adverse events (AEs) were resolved without sequelae; no serious AEs were reported. Two drugs showed similar tendencies to lower blood pressure in healthy subjects.
Conclusions: The PK profiles of AGSAV301 and Exforge were bioequivalent. Both drugs were also well tolerated, with comparable AE profiles and similar blood pressure-lowering tendencies in healthy volunteers, suggesting equivalent therapeutic indications.