ObjectiveThe primary objective of this double-blind, parallel-group, placebo-controlled, multicentre study was to compare the antihypertensive efficacy of one versus two daily doses of eprosartan, a novel nonbiphenyl, nontetrazole angiotensin II receptor antagonist, in 243 patients with mild to moderate hypertension (sitting diastolic blood pressure ≥ 95 to ≤ 114 mmHg).Patients and methodsThe patients were randomized to titrated doses of eprosartan at 400–800 mg once a day, eprosartan at 200–400 mg twice a day, or placebo, with the incremental dose titrated over a 9-week period. Patients reaching target blood pressure (sitting diastolic blood pressure of ≤ 90 mmHg) continued the fixed-dose treatment for 4 weeks. The primary efficacy measure was the mean change in trough sitting diastolic blood pressure from baseline to the study endpoint, determined on an intent-to-treat basis.ResultsBy the end of the study, eprosartan had significantly reduced mean trough sitting systolic and diastolic blood pressure relative to baseline and to placebo. The mean ± SD change from baseline in diastolic pressure was −9 ± 8.4 mmHg for the single daily dose, −9 ± 8.5 mmHg for two doses a day and −4 ± 8.1 mmHg for placebo (P< 0.0001 versus placebo for both eprosartan regimens). Similarly, both eprosartan regimens significantly reduced mean trough standing systolic and diastolic blood pressure. At the end of the study, the response rate in the single daily dose group (46.8%) was significantly higher than in the placebo group (25.6%). There were no significant differences between the treatment groups in the number of patients whose blood pressure responded to treatment; 41.7% of those taking eprosartan once a day and 44.4% of those taking eprosartan twice a day, and who responded to treatment, were maintained on their original starting doses. The total daily dose required to achieve target blood pressure was comparable, whether eprosartan was administered once or twice a day. Both eprosartan regimens were well tolerated and the incidence of adverse events with eprosartan was similar to that of placebo.ConclusionsThese results demonstrate that there was no significant difference in antihypertensive efficacy or tolerance between eprosartan taken in one or in two daily doses. Both dosing regimens provided significant and clinically meaningful reductions in blood pressure that were superior to placebo. Eprosartan in a single daily dose was shown to be an effective antihypertensive agent. Because of the good adverse-effect profile and the simplicity of a single daily dose, eprosartan has the potential to improve patient compliance.