The benefits of valsartan (Val)/hydrochlorothiazide (HCTZ) combination as initial treatment for hypertension were evaluated in a post hoc analysis of an 8-week, double-blind, placebo-controlled, parallel-group trial. The highest dose of Val/HCTZ combination (320/25 mg), component monotherapies (Val 320 mg, HCTZ 25 mg) and placebo were selected for this analysis (N=675, 52.1% men, 68.6% Caucasians, mean age 52.9 years, baseline blood pressure (BP) 150.6/99.1 mm Hg). As soon as 2 weeks after initiation of active therapy, greater BP control rates were observed with Val/HCTZ (320/25 mg) compared with Val (320 mg), HCTZ (25 mg) and placebo. Similar results were observed in subgroups of patients with stage 1 and stage 2 hypertension, as well as in diabetic patients. As baseline BP increased, the probability of achieving mean sitting systolic BP (<140 and <130 mm Hg) and mean sitting diastolic BP control (<90 and <80 mm Hg), determined using a logistic regression model, decreased with all treatments. However, at all levels of baseline BP, the probability of achieving BP control was greater with Val/HCTZ combination. The Val/HCTZ combination was well tolerated with overall incidence of adverse events similar to that observed with monotherapy and placebo. These results support the use of Val/HCTZ combination as initial therapy in hypertensive patients unlikely to achieve BP control with a single agent.