Valsartan: a novel angiotensin type 1 receptor antagonist

Valsartan is a highly selective, orally available antagonist of the angiotensin Type 1 (AT1) receptor. It is indicated for treatment of mild to moderate essential hypertension. Experimental studies have confirmed the abolition or attenuation of angiotensin II (AII)-related effects, such as vasoconstriction, cell growth promotion and aldosterone release. In humans, valsartan is rapidly absorbed with maximal plasma concentrations occurring 1-2 h after oral administration. The elimination half-life comes to about 7-8 h, valsartan is metabolised to a negligible extent and most of the drug is excreted via the faeces. There is no dose adjustment required for patients with a creatinine clearance > 10 ml/min. The dose should not exceed 80 mg o.d. in patients with hepatic dysfunction, valsartan is not recommended for patients with severe hepatic dysfunction and/or biliary cirrhosis. At present, no clinically relevant pharmacokinetic drug interactions have been observed. Valsartan produces persistent blood pressure reductions in patients with mild to moderate hypertension, the recommended starting dose is 80 mg o.d. If required, the dose may either be increased to 160 mg o.d. or hydrochlorothiazide may be added. In comparison to other antihypertensive drugs valsartan therapy leads to similar blood pressure reductions, while exhibiting a favourable tolerability profile. Preliminary studies suggest beneficial effects in patients with hypertensive end-organ damage such as renal disease and left ventricular hypertrophy. Furthermore, the drug is evaluated for its efficacy in heart failure and patients post-myocardial infarction.