Angiotensin II receptor antagonists (AIIRA): which drug combinations and which perspectives

AIIRA have the same therapeutic effects as ACE-inhibitors, but they have different mechanisms of action. Unlike AIIRA, ACE-inhibitors inhibit the metabolism of bradykinin, but following prolonged use, levels of angiotensin II return to baseline levels. In contrast, AIIRA selectively block angiotensin receptors AT(1) while stimulation of the receptors AT(2)-with its inherent benefits-is maintained. It is therefore reasonable to conclude that the combination of an ACE-inhibitor and an AT(1)-blocker will result in a more complete blockage of angiotensin II, although the clinical efficacy of such a combination has yet to be confirmed. In a number of clinical trials combination therapy with AIIRA and ACE-inhibitors has be shown to be more beneficial than monotherapy with the individual drugs on renal function in patients with nephropathy (diabetic and non-diabetic). Although results of studies in patients with heart failure are controversial, the addition of an AIIRA is beneficial in patients treated with ACE-inhibitors and who are unsuitable for treatment with beta-blockers, however, there is controversy regarding these results. Additional studies, together with results of currently ongoing clinical trials, are necessary in order to clarify the benefits of this combination as well investigating the efficacy of AIIRA combined with calcium antagonists and statins in cardiovascular disease prevention.