General Information

Azor is a combination of the angiotensin II receptor antagonist olmesartan, and the calcium channel blocker amlodipine. The amlodipine component of Azor inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle, and the olmesartan medoxomil component of Azor blocks the vasoconstrictor effects of angiotensin II.

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

Azor is supplied as a tablet designed for oral administration. The drug comes in four strengths; the amlodipine dose is listed first and the olmesartan dose is listed second (both in mg): 5/20, 5/40, 10/20 and 10/40. The dosage may be increased after two weeks. The maximum recommended dose of Azor is 10/40.

Clinical Results

FDA Approval
FDA approval of Azor was based on the results of several clinical trials.

Azor
An 8-week, multi-center, double-blind, randomized, placebo controlled, parallel group, factorial study enrolled 1,940 subjects with mild to severe hypertension. The subjects were placed in one of 12 treatment arms to receive placebo, monotherapy treatment with amlodipine 5 mg or 10 mg, monotherapy treatment with olmesartan medoxomil 10 mg, 20 mg, or 40 mg, or combination therapy with amlodipine/olmesartan medoxomil (Azor) at doses of 5/10 mg, 5/20 mg, 5/40 mg, 10/10 mg, 10/20 mg, and 10/40 mg. Results showed that all combinations produced greater mean reductions in blood pressure than either drug alone. The highest combination dose was amlodipine 10 mg plus 40 mg olmesartan. At this dose systolic blood pressure was cut by 30.1 mm Hg, a 53% greater drop than with 10 mg amlodipine alone. Diastolic blood pressure on this dose was reduced by 19 mm Hg, compared to 12.7 for amlodipine alone.

Amlodipine
The anti-hypertensive activity of amlodipine was evaluated in 15 double-blind, placebo-controlled, randomized studies. The trials enrolled a total of 1,338 subjects with mild to moderate hypertension who were treated with amoldipine or placebo once daily. Amoldipine resulted in statistically significant placebo-corrected reductions in supine and standing blood pressures at 24 hours postdose, averaging about 12/6 mmHg in the standing position and 13/7 mmHg in the supine position. Maintenance of the blood pressure effect over the 24-hour dosing interval was observed, with little difference in peak and trough effect.

Olmesartan medoxomil
The anti-hypertensive activity of olmesartan was evaluated in 7 placebo controlled studies. A total of 2,693 subjects with essential hypertension were enrolled and received placebo or olmesartan at doses ranging from 2.5 mg to 80 mg, for 6 to 12 weeks. The blood pressure lowering effect was maintained throughout the 24-hour period, with trough-to-peak ratios for systolic and diastolic response between 60% and 80%.

Mechanism of Action

Literature References

Chrysant SG, Marbury TC, Silfani TN Use of 24-h ambulatory blood pressure monitoring to assess blood pressure control: a comparison of olmesartan medoxomil and amlodipine besylate. Blood Pressure Monitoring 2006 Jun;11(3):135-41

Quan A, Chavanu K, Merkel J A review of the efficacy of fixed-dose combinations olmesartan medoxomil/hydrochlorothiazide and amlodipine besylate/benazepril in factorial design studies. American Journal of Cardiovascular Drugs : drugs, devices, and other interventions 2006;6(2):103-13

Neutel JM, Smith DH, Silfani TN, Lee Y, Weber MA Effects of a structured treatment algorithm on blood pressure goal rates in both stage 1 and stage 2 hypertension. Journal of Human Hypertension 2006 Apr;20(4):255-62

Neutel JM, Smith DH, Weber MA, Wang AC, Masonson HN Use of an olmesartan medoxomil-based treatment algorithm for hypertension control. Journal of Clinical Hypertension 2004 Apr;6(4):168-74