General Information

Edarbi (azilsartan medoxomil), a prodrug, is hydrolyzed to azilsartan in the gastrointestinal tract during absorption. Azilsartan is a selective AT1 subtype angiotensin II receptor antagonist. It's mechanism of action is to lower blood pressure by inhibiting action of vasopressor hormone Angiotensin II, a polypeptide that causes vasoconstriction, increased blood pressure and aldosterone release.

Edarbi is specifically indicated for the treatment of hypertension, alone or in combination with other antihypertensive agents.

Edarbi is supplied as a tablet for oral administration. The recommended initial dose in adults is 80 mg taken orally once daily.

Clinical Results

FDA Approval
The FDA approval of Edarbi was based on seven double-blind, randomized studies. A total of 5,941 subjects with mild, moderate or severe hypertension were studied. The subjects received Edarbi (n=3,672), placebo (n=801) or active comparator (n=1,468). Two 6-week randomized, double blind studies compared the effect on blood pressure of Edarbi at doses of 40 mg and 80 mg, with placebo and with active comparators. Blood pressure reductions compared to placebo were based on clinic blood pressure measurements at trough and 24 hour mean blood pressure by ambulatory blood pressure monitoring (ABPM). Edarbi, 80 mg, was statistically superior to placebo and active comparators for both clinic and 24 hour mean blood pressure measurements.
Edarbi also showed a sustained and consistent antihypertensive effect during long-term treatment, as shown in a study that randomized patients to placebo or continued Edarbi after 26 weeks. No rebound effect was observed following the abrupt cessation of Edarbi therapy.

Mechanism of Action

Edarbi, a prodrug, is hydrolyzed to azilsartan in the gastrointestinal tract during absorption. Azilsartan is a selective AT1 subtype angiotensin II receptor antagonist. Angiotensin II is formed from angiotensin I in a reaction catalyzed by angiotensin-converting enzymes (ACE, kinase II). Angiotensin II is the principal pressor agent of the renin-angiotensin system, with effects that include vasoconstriction, stimulation of synthesis and release of aldosterone, cardiac stimulation, and renal reabsorption of sodium. Azilsartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor in many tissues, such as vascular smooth muscle and the adrenal gland. Its action is, therefore, independent of the pathway for angiotensin II synthesis.

Literature References

White WB, Weber MA, Sica D, Bakris GL, Perez A, Cao C, Kupfer S Effects of the angiotensin receptor blocker azilsartan medoxomil versus olmesartan and valsartan on ambulatory and clinic blood pressure in patients with stages 1 and 2 hypertension. Hypertension 2011 Mar;57(3):413-20

Bakris GL, Sica D, Weber M, White WB, Roberts A, Perez A, Cao C, Kupfer S The comparative effects of azilsartan medoxomil and olmesartan on ambulatory and clinic blood pressure. Journal of Clinical Hypertension (Greenwich) 2011 Feb;13(2):81-8. doi: 10.1111/j.1751-7176.2010.00425.x.