valsartan

valsartan
Name	Valsartan
Tradename	Diovan and others
Routes of administration	Oral, intravenous (investigational)
Legal status	Prescription-only
Class	Angiotensin II receptor blocker
Protein bound	~95%
Metabolism	Minimal hepatic
Elimination half-life	~6 hours
Excretion	Renal and fecal

valsartan is an angiotensin II type 1 receptor antagonist used primarily to treat hypertension, heart failure, and to reduce morbidity after myocardial infarction. It is prescribed worldwide and appears in treatment guidelines from organizations such as the World Health Organization, American Heart Association, and European Society of Cardiology. Clinical outcomes associated with valsartan have been compared in randomized trials involving institutions like the National Institutes of Health, Cleveland Clinic, and Mount Sinai Health System.

Medical uses

Valsartan is indicated for the management of essential hypertension, heart failure with reduced ejection fraction, and for improving survival after acute myocardial infarction. Large landmark trials and guideline panels such as the VALIANT trial, ALLHAT investigators, and committees from the National Heart, Lung, and Blood Institute have informed its use in adults. It is also used off-label in selected patients with left ventricular dysfunction evaluated by centers like Mayo Clinic, Johns Hopkins Hospital, and Massachusetts General Hospital.

Pharmacology

Valsartan selectively blocks the angiotensin II type 1 (AT1) receptor, inhibiting actions of angiotensin II produced by the renin–angiotensin system and modulating vascular tone and aldosterone secretion; mechanistic studies have been conducted at institutions such as Scripps Research Institute, Karolinska Institute, and University of Oxford. Its pharmacokinetics show high plasma protein binding and predominantly renal and biliary excretion, characterized in pharmacology labs at Food and Drug Administration submissions and analyzed by groups at Pfizer and academic pharmacology departments at University of California, San Francisco. Valsartan does not inhibit angiotensin-converting enzyme and therefore does not increase bradykinin levels like agents compared in trials at Imperial College London and Harvard Medical School.

Adverse effects

Common adverse effects include dizziness, hypotension, and renal function changes documented in safety reports reviewed by regulators such as the European Medicines Agency and Medicines and Healthcare products Regulatory Agency. Postmarketing surveillance by organizations including the Centers for Disease Control and Prevention, World Health Organization, and national pharmacovigilance centers has reported rare events like angioedema and hyperkalemia; case series and reports have been published by hospitals such as Guy's and St Thomas' NHS Foundation Trust and Toronto General Hospital. Concerns about impurities and contaminant nitrosamines emerged in recalls coordinated with agencies like the U.S. Food and Drug Administration and manufacturers including Ranbaxy Laboratories and Sun Pharmaceutical Industries.

Dosage and administration

Typical oral dosing for hypertension starts at low to moderate doses with titration similar to protocols from the JNC 8 recommendations and European guidelines from the European Society of Cardiology. Heart failure regimens reference outcome trials such as those run by the CONSENSUS and SOLVD study groups when determining target doses in tertiary centers like Cleveland Clinic. Dosing adjustments are recommended for patients with renal impairment per product monographs reviewed by the Food and Drug Administration and clinical pharmacy departments at universities like University of Toronto.

Contraindications and precautions

Valsartan is contraindicated in patients with known hypersensitivity to the product and in pregnancy because of fetal toxicity identified in teratology studies and guidance from agencies such as the American College of Obstetricians and Gynecologists and European Medicines Agency. Caution is advised in patients with bilateral renal artery stenosis, monitored by nephrology units at centers including Necker–Enfants Malades Hospital and Johns Hopkins Hospital, and in those with severe hepatic impairment per hepatology guidance from organizations such as the British Association for the Study of the Liver.

Drug interactions

Valsartan's interactions include additive hypotensive effects with calcium channel blockers studied by cardiology groups at Mount Sinai Hospital and potential potassium elevation when combined with potassium-sparing diuretics or supplements as highlighted by pharmacists at Mayo Clinic. Concomitant use with nonsteroidal anti-inflammatory drugs, evaluated in clinical pharmacology trials at University of Pennsylvania, may attenuate antihypertensive effects and increase renal risk. Drug–drug interaction assessments have been included in regulatory reviews by the U.S. Food and Drug Administration and pharmacology reviews at Pfizer.

History and development

Valsartan was developed in the 1980s and 1990s through programs at pharmaceutical companies including Novartis and Bristol-Myers Squibb, with clinical development programs involving academic collaborators from institutions such as Duke University, University College London, and Karolinska Institute. The drug was approved in multiple jurisdictions after pivotal trials like the VALIANT and postmarketing studies overseen by regulators such as the U.S. Food and Drug Administration and European Medicines Agency, and its patent and commercial history involved legal and corporate actions similar to cases handled by firms represented in landmark litigation in the United States District Court system. Manufacturing, supply, and quality issues leading to recalls were managed by national authorities including the U.S. Food and Drug Administration and European Commission.

Category:Angiotensin II receptor antagonists