Patients on two or more antihypertensive drugs with MSSBP ≥ 180 mmHg and/or MSDBP ≥ 110 mmHg at Visit 1.

Patients on three or more antihypertensive drugs with MSDBP ≥ 90 mmHg and \< 110 mmHg, and/or MSSBP ≥ 140 mmHg and \< 180 mmHg at Visit 1.

Patients on four or more antihypertensive drugs at Visit 1.

Arm circumference \> 42 cm for patients participating in ABPM.

8-week Study to Evaluate Safety and Efficacy of Various Combinations of Valsartan, HCTZ, and Amlodipine in Patients With Moderate to Severe Hypertension