Olmesartan (RNH 6270) is an Angiotensin II Type I receptor antagonist. Olmesartan is the active form of the antihypertensive drug olmesartan medoxomil,and has antihypertensive activity.

The target blood pressure (<130/80 mm Hg) was achieved in nearly 80% of the patients taking olmesartan and 71% taking placebo;?blood pressure measured in the clinic was lower by 3.1/1.9 mm Hg in the olmesartan group than in the placebo group.?Microalbuminuria developed in 8.2% of the patients in the olmesartan group (178 of 2160 patients who could be evaluated) and 9.8% in the placebo group (210 of 2139);?the time to the onset of microalbuminuria was increased by 23% with olmesartan (hazard ratio for onset of microalbuminuria, 0.77;?95% confidence interval, 0.63 to 0.94;?P=0.01).?The serum creatinine level doubled in 1% of the patients in each group.?Slightly fewer patients in the olmesartan group than in the placebo group had nonfatal cardiovascular events--81 of 2232 patients (3.6%) as compared with 91 of 2215 patients (4.1%) (P=0.37)--but a greater number had fatal cardiovascular events--15 patients (0.7%) as compared with 3 patients (0.1%) (P=0.01),?a difference that was attributable in part to a higher rate of death from cardiovascular causes in the olmesartan group than in the placebo group among patients with preexisting coronary heart disease (11 of 564 patients [2.0%] vs. 1 of 540 [0.2%], P=0.02)[1].

In a randomized, double-blind, multicenter, controlled trial, Assigned 4447 patients with type 2 diabetes to receive olmesartan (at a dose of 40 mg once daily) or placebo for a median of 3.2 years.?Additional antihypertensive drugs (except angiotensin-converting-enzyme inhibitors or ARBs) were used as needed to lower blood pressure to less than 130/80 mm Hg. The primary outcome was the time to the first onset of microalbuminuria.?The times to the onset of renal and cardiovascular events were analyzed as secondary end points[1].