Azilsartan Medoxomil: A New Angiotensin II Receptor Antagonist for Treatment of Hypertension

Abstract

To evaluate the efficacy, safety, and clinical role of azilsartan medoxomil, an angiotensin II receptor blocker (ARB) that recently gained Food and Drug Administration approval for lowering of blood pressure (BP) in patients with hypertension. A systematic review of the literature was performed through August 2011 using MEDLINE, Web of Science, and International Pharmaceutical Abstracts and the key words and MeSH terms azilsartan, azilsartan medoxomil, TAK-491, TAK-536, and Edarbi. Abstracts presented in the last 2 years from the annual meetings of appropriate medical societies were reviewed in addition to a search of clinicaltrials.gov. Studies eligible for inclusion were in vitro or in vivo evaluations of azilsartan medoxomil, with no restrictions on patient population or indication. Data related to the patient populations and outcomes of interest were extracted from each publication. Three trials are available in full publication form with others available only as abstracts. Azilsartan medoxomil 40 mg and 80 mg daily significantly improves both systolic and diastolic BP from baseline compared with placebo, and the 80-mg dose has greater efficacy than other ARBs, including olmesartan 40 mg daily and valsartan 320 mg daily. Improvements in both 24-hour BP using ambulatory monitoring and clinic monitoring have been seen with azilsartan medoxomil as well as a higher proportion of patients reaching the goal level. Additional information shows added BP lowering when azilsartan medoxomil is combined with chlorthalidone. Adverse events are similar with azilsartan medoxomil versus other ARBs and include headache, dizziness, urinary tract infections, and fatigue. Azilsartan medoxomil is a safe and effective ARB with a unique pharmacologic profile versus other agents, including slowed angiotensin II type 1 receptor dissociation rates and improved receptor specificity. Studies have shown azilsartan medoxomil 80 mg once daily to reduce BP to a greater extent than valsartan and olmesartan, with similar safety and tolerability.