A comparison of the efficacy and duration of action of telmisartan, amlodipine and ramipril in patients with confirmed ambulatory hypertension.

Author(s): Poirier L, de Champlain J, Larochelle P, Lamarre-Cliche M, Lacourciere Y

Affiliation(s): Unite d'hypertension, Centre Hospitalier de l'Universite Laval, Universite Laval, 2705 Boulevard Laurier S-120-A, Sainte-Foy, Quebec, Canada G1V 4G2. luc.poirier@crchul.ulaval.ca

Publication date & source: 2004-10, Blood Press Monit., 9(5):231-6.

Publication type: Clinical Trial; Randomized Controlled Trial

OBJECTIVES: The aim of the study was to compare the antihypertensive effects and the duration of action of telmisartan, amlodipine and ramipril in patients with mild-to-moderate hypertension using ambulatory blood pressure (ABP) monitoring. METHODS: After a 2-4-week single-blind, placebo run-in period, qualifying patients were randomized to receive telmisartan 80 mg (n=18); amlodipine 5 mg (n=22); titrated to 10 mg after 4 weeks; or ramipril 2.5 mg (n=17); titrated to 5 mg and 10 mg after 1 and 3 weeks, respectively, administered once daily in the morning (0700 h). Ambulatory blood pressure monitoring was performed at baseline and at the end of the 8-week treatment period. Plasma renin activity was measured over 24 h at the same time points. RESULTS: Telmisartan and amlodipine provided significant reductions from baseline (P<0.0001) and not statistically different reductions between treatments in ABP during daytime (9.3/6.0 and 14.7/9.4 mmHg, respectively) and night-time (12.4/7.7 and 13.3/8.6 mmHg, respectively) at the end of 8 weeks' treatment. In contrast, although ramipril provided significant reductions in ambulatory systolic and diastolic BP from 2-6 h post dose (peak effect), it failed to induce significant reductions in mean daytime (4.5/1.6 mmHg) and night-time (1.8/0.1 mmHg) ambulatory BP. In addition, the greater reductions in ABP with telmisartan and amlodipine were associated with a significant rise in plasma renin activity whereas ramipril only increased renin during the first 4 h of the administration interval. CONCLUSION: The results of the present study confirm the efficacy of both telmisartan and amlodipine in reducing ABP during each period of the 24-h interval. Because ABP reduction with ramipril was restricted to its peak effect, the present data do not support the use of this agent when administered once daily in the morning.