Efficacy and safety of olmesartan medoxomil 40 mg/hydrochlorothiazide 12.5 mg combination therapy versus olmesartan medoxomil 40 mg monotherapy in patients with moderate to severe hypertension: a randomized, double-blind, parallel-group, multicentre, multinational, phase III study.

Background: Current hypertension guidelines recommend using two antihypertensive agents when blood pressure (BP) control is not achieved with one single agent.

Objective: This study was designed to assess the antihypertensive benefit of the olmesartan medoxomil 40 mg/hydrochlorothiazide (HCTZ) 12.5 mg combination versus olmesartan medoxomil 40 mg monotherapy in patients with moderate to severe hypertension.