Амбризентан

Ambrisentan is a selective endothelin-A (ETA) receptor antagonist introduced for the oral treatment of patients with pulmonary arterial hypertension (PAH), to improve exercise capacity and delay clinical worsening. It is the third ET-receptor antagonist to be marketed for this indication behind bosentan and sitaxsentan. PAH is a rare disease of the small pulmonary arteries characterized by vascular proliferation and remodeling, resulting in a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, and ultimately, right ventricular failure and premature death. Early symptoms of PAH include gradual onset of shortness of breath, fatigue, palpitation, edema, and fainting. Endothelin-1 (ET-1), a potent vasoconstrictor and smooth muscle mitogen, is a key contributor to the acceleration of the disease, and its effects are mediated through activation ofET_A and ET_B receptors.

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Nonpeptide endothelin ETA receptor antagonist. Antihypertensive

Ambrisentan, (+)-(2S)-2-[(4,6-dimethylpyrimidin-2-yl)oxy]-3-methoxy-3,3-diphenylpropanoic acid(Letairis), is a potent ETA selective endothelin antagonist that,is indicated, in the treatment of pulmonary arterial hypertension(PAH). PAH is a rare disease that if left untreated has ahigh mortality rate. In June of 2007, the FDA granted approvalof ambrisentan for once-daily treatment of PAH.Studies have shown that it improves a 6-minute walk by about30 to 60 m for patients receiving placebo.