This study is designed as a mechanistic study to compare the effect of two different combinations of anti-hypertensive treatments (aliskiren and valsartan vs. telmisartan and ramipril) on the renin-angiotensin-aldosterone system (RAAS) in patients with moderate hypertension.

Inclusion Criteria:

• Males or females of non-childbearing potential, 18 to 65 years of age with moderate hypertension
• Patients who are eligible and able to participate in the study

Exclusion criteria:

• Severe hypertension or secondary form of hypertension.
• Serum potassium > 5.1 mEq/L (mmol/L)
• Heart failure
• Any history of hypertensive encephalopathy or cerebrovascular accident; any history of TIA, myocardial infarction, coronary bypass surgery or percutaneous coronary intervention
• Uncontrolled or life-threatening arrythmia

Other protocol-defined inclusion/exclusion criteria may apply