Background: Olmesartan medoxomil is an angiotensin II receptor antagonist that selectively and competitively inhibits the angiotensin II type 1 receptor.
Objective: This article reviews the results of some key studies that assessed the efficacy and tolerability of olmesartan in patients with hypertension.
Methods: Olmesartan has been investigated in several clinical studies. This article reports on data from 1 such study with a prospective, randomized, double-blind, placebo-controlled, parallel-group, dose-finding design in patients with mild to moderate hypertension (baseline mean sitting diastolic blood pressure, 100-114 mm Hg). The results from a meta-analysis of 7 randomized, double-blind, placebo-controlled studies are also presented.
Results: In the dose-finding study, 792 patients were randomized to olmesartan (2.5-80 mg) or placebo once daily, and changes were recorded in trough mean sitting diastolic and systolic blood pressures from baseline to the end of a 12-week treatment period. For the meta-analysis, 3055 patients were randomized to treatment; 2511 received olmesartan. In the dose-finding study as well as in the meta-analysis, olmesartan (2.5-80 mg once daily) produced a dose-dependent decrease in diastolic and systolic blood pressures, and at a dose of 10 to 80 mg showed significant superiority in reducing diastolic blood pressure over placebo (P < 0.05). The 20-mg dose was considered optimal, with a responder rate of 70%. Furthermore, in a 2-year study with 462 patients, olmesartan had a good safety profile and was well tolerated. The results of the clinical studies in >3000 patients receiving olmesartan showed that the frequency and profile of adverse events with olmesartan were generally similar to those with placebo; the frequency of adverse events was not dose related. Olmesartan, with or without hydrochlorothiazide, was well tolerated over 2 years of treatment.