The authors report on the 44-week open-label extension of the 8-week, double-blind Combination of Olmesartan Medoxomil and Amlodipine Besylate in Controlling High Blood Pressure (COACH) trial in 1684 patients. Initial therapy was amlodipine (AML) plus olmesartan medoxomil (OM) 5+40 mg/d, up-titrated to AML+OM 10+40 mg/d plus hydrochlorothiazide (HCTZ) 12.5 mg then 25 mg if patients did not achieve blood pressure (BP) goal (<140/90 mm Hg or <130/80 mm Hg in patients with diabetes). Baseline mean BP decreased from 164/102 mm Hg to 131/82 mm Hg at end of study, with an overall 66.7% of patients, including those with diabetes, achieving BP goal. The BP goal achievement was 80% for AML+OM 5+40 mg/d, 70.6% for AML+OM 10+40 mg/d, 66.6% for AML+OM+HCTZ 10+40+12.5 mg/d, and 46.3% for AML+OM+HCTZ 10+40+25 mg/d. Study medication was safe and well tolerated. Combination antihypertensive therapy with AML+OM±HTCZ, up-titrated as necessary, allowed a majority of patients to achieve BP goal.