Clinical evidence from ONTARGET: the value of an angiotensin II receptor blocker and an angiotensin-converting enzyme inhibitor.

The Heart Outcomes Prevention Evaluation study established the angiotensin-converting enzyme inhibitor ramipril, versus placebo, for prevention of cardiovascular events in high-risk patients. The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) was later conducted in similar high-risk patients using multifactorial treatment to control hypertension, platelet aggregation, and dyslipidemia, while comparing ramipril, telmisartan, or their combination, without placebo. In ONTARGET, the first angiotensin II receptor blocker-based study to be performed in a broader population of patients without congestive heart failure and/or left ventricular hypertrophy/dysfunction, telmisartan provided cardiovascular protection that was noninferior to ramipril. However, greater blockade of the renin-angiotensin system, using their combination, was not superior to ramipril alone. Telmisartan was better tolerated than ramipril in this high-risk population: notably, the incidence of cough and angioedema was significantly lower with telmisartan alone. Thus, telmisartan provides comparable efficacy to ramipril with less adverse events, which may encourage patient compliance.