Telmisartan (
Micardis) is a potent, long-lasting, nonpeptide
angiotensin II type-1 (AT(1)) receptor blocker (ARB) that is indicated for the treatment of
essential hypertension. In receptor binding studies,
telmisartan showed a high affinity and selectivity for the human AT(1) receptors compared with AT(2) receptors and a slower dissociation rate from the human AT(1) receptor than those of ARBs. In isolated aorta rings,
telmisartan was shown to be an insurmountable antagonist of AII-induced contractions. The inhibitory effects of
telmisartan on AII-induced contraction persisted even after wash-out procedures. In animal models such as spontaneous
hypertension rats and renovascular hypertensive rats,
telmisartan produced the consistent reduction of blood pressure. Furthermore, there were no rebound phenomenon and no tolerance to the
drug developed in the repeated
oral administration.
Telmisartan has a longer terminal elimination half-life (about 24 h) than the other ARBs. In patients with mild-moderate
hypertension, trough/peak ratios for
telmisartan were above 80%. In Japanese patients with mild-moderate
hypertension,
telmisartan produced a significant reduction in blood pressure (effective rate: 76.0%) with a good safety profile. Therefore,
telmisartan is expected to be effective in the treatment of
hypertension, producing sustained 24-h blood pressure control.