Vascular protection: telmisartan in the ONTARGET Trial Programme

Abstract

The ONTARGET Trial Programme includes the ONTARGET and TRANSCEND studies. In both studies, participants were at high cardiovascular risk because they had vascular disease without heart failure, or diabetes with end-organ damage. Participants also received proven therapies for cardiovascular risk reduction. In ONTARGET, telmisartan 80 mg was compared with ramipril 10 mg, and the combination of telmisartan and ramipril was compared with ramipril alone. Telmisartan was as effective as ramipril on the primary outcome and other cardiovascular events and was better tolerated, with fewer treatment discontinuations. In TRANSCEND, telmisartan and placebo, both added to background therapy, were compared in high-risk patients intolerant to angiotensin-converting enzyme-inhibitors. There was a lower incidence of cardiovascular events than assumed in power calculations probably due to higher use of background therapy than expected based upon the HOPE trial. This may explain why the reduction in the primary outcome associated with telmisartan was not statistically significant. Nevertheless, the results of TRANSCEND were consistent with the outcome of the HOPE trial, and the secondary endpoint in TRANSCEND, which was equal to the HOPE primary endpoint (cardiovascular death, myocardial infarction, and stroke), was indeed significant. Telmisartan plus ramipril did not reduce the primary outcome compared with ramipril alone and was associated with a greater likelihood of adverse events. The combination is not recommended for the prevention of cardiovascular events in this patient population. In summary, telmisartan was as effective as ramipril on major vascular events in high-risk patients in ONTARGET but showed a non-significant benefit in TRANSCEND. In both studies, the lower rate of treatment discontinuations with telmisartan is important life-long adherence to therapy.