Triple antihypertensive combination therapy offers greater blood pressure reductions compared with dual treatments

Results of a new study found that the investigational triple combination therapy of olmesartan medoxomil (OM), amlodipine besylate (AML), and hydrochlorothiazide (HCTZ), demonstrated significantly greater mean reductions at week 12 in blood pressure (37.1/21.8 mmHg vs 27.5 to 30.0/15.1-18.0 mmHg LS mean reductions, P<.0001), as compared with corresponding dual combination therapy.

The TRINITY study (Triple Therapy with Olmesartan Medoxomil, Amlodipine, and Hydrochlorothiazide in Hypertensive Patients Study) is a phase 3, multicenter, randomized, parallel-group study, which included 2,492 patients with moderate-to-severe hypertension. The study consisted of a double-blind, 12-week treatment period, followed by a 40-week open-label period.

“This study demonstrated that treating patients with a triple combination therapy regimen of olmesartan, amlodipine, and hydrochlorothiazide, each medication with a different mechanism of action, is more effective at lowering blood pressure than combining any of the 2 medications. This is important because many patients with hypertension fail to reach recommended blood pressure targets even when taking more than one therapy,” Suzanne Oparil, MD, professor of medicine and physiology and biophysics at the University of Alabama School of Medicine, Birmingham, told Formulary.

The study, presented at the American Society of Hypertension (ASH) annual meeting in May, also found that at week 12, a significantly greater percentage of patients treated with the investigational triple combination therapy (OM/AML/HCTZ 40/10/25 mg) reached blood pressure goal (<140/90 mmHg or <130/80 mmHg for patients with diabetes), as compared with corresponding dual components (64.3% vs 34.9%-46.6%).

According to Dr Oparil, studies have shown that combination therapy with 2 or more drugs provides better blood pressure control than single therapy alone, "which in turn may prevent more cardiovascular events, which would help to reduce costs associated with hospitalizations or the need for specialized medical procedures, as well as fewer office visits to monitor blood pressure and titrate doses of antihypertensive medication," she said.

Dr Oparil added that patients would likely have better adherence to medication in that they are more likely to follow the prescription of taking one single pill a day, which consists of 3 different medications, than following the prescription for 3 separate medications.

At this time, Dr Oparil said that there are very few new drug classes being developed for the treatment of hypertension. "However, the market is focusing on developing more dual and triple combination therapies because we know most hypertension cannot be adequately controlled with monotherapy alone," she said.

"There potentially will be a new triple drug combination therapy available that is effective at lowering blood pressure in patients with moderate-to-severe hypertension regardless of gender, age, race, and hypertension severity," Dr Oparil continued.

Dr. Oparil  is an advisor/consultant for Forest, Daiichi Sankyo, Bristol-Myers Squibb, Novartis, Sanofi-Aventis, The Salt Institute, NicOx, and Boehringer-Ingelheim. She received grant/research support from Daiichi Sankyo, Novartis, Gilead, Forest, and Takeda. She is part of the speaker's bureau/speaking/teaching for Daiichi Sankyo, Forest, and Merck. She is a member of the American Society of Hypertension board of directors.