OBJECTIVE: The present article reviews 3 head-to-head trials directly comparing the
antihypertensive efficacy of
olmesartan with that of 4 other AIIRAs, at recommended maintenance doses, already in clinical use for the treatment of
hypertension.
RESULTS: In the first study,
olmesartan 10 mg/d was compared with
losartan 50 mg/d in 316 patients with mild to moderate
hypertension (mean baseline diastolic blood pressure [DBP], 95-114 mm Hg). Dosage was doubled at week 4 and
hydrochlorothiazide was added at week 12 if blood pressure response was inadequate.
Olmesartan was significantly more effective than
losartan with respect to the reduction in blood pressure at weeks 2, 4, and 12, and to the responder rate at weeks 2 and 4 (with the starting dose of the respective
drug). In a second study,
olmesartan 20 mg/d was shown to be significantly more effective than
losartan 50 mg/d,
valsartan 80 mg/d, and
irbesartan 150 mg/d in 588 patients with mild to moderate
hypertension (mean sitting baseline DBP, 100-115 mm Hg) (P < or = 0.05). At week 2, the reduction in blood pressure observed with
olmesartan was significantly greater than that of the comparator treatments (P < or = 0.05). The superiority of
olmesartan was maintained at week 8. The third study involved 643 evaluable patients with moderate to severe
hypertension (mean DBP, 100-120 mm Hg; mean systolic blood pressure, >150 mm Hg).
Olmesartan 20 mg/d was more effective than
candesartan 8 mg/d in lowering 24-hour blood pressure at week 8 (P < or = 0.05). Most of this treatment effect was evident after only 1 or 2 weeks, with greater reductions in blood pressure compared with
candesartan.
CONCLUSIONS: These data indicate that, at the doses studied,
olmesartan is more effective than other AIIRAs tested at their recommended doses, in terms of reduction of cuff or 24-hour ambulatory blood pressure, in patients with
essential hypertension. These differences in blood pressure reduction between these agents may be clinically relevant and have important long-term implications. Additional studies will further define the role of
olmesartan in the management of
cardiovascular diseases, such as
atherosclerosis.