[6] Ambrisentan significantly improved exercise capacity (6-minute walk distance) compared with placebo in two double-blind, multicenter trials (ARIES-1 and ARIES-2).

[9][4][10][11] Ambrisentan is indicated for the treatment of pulmonary arterial hypertension (WHO Group 1) in people with WHO class II or III symptoms to improve exercise capacity and delay clinical worsening.

[3][4] Ambrisentan is a drug that blocks endothelin, an endogenous hormone found in higher quantities in patients with pulmonary arterial hypertension.

Endothelin receptor activation mediates strong pulmonary vasoconstriction and positive inotropic effect on the heart.

In addition to this, endothelin receptors are also known to play a role in neural crest cell migration, growth, and differentiation.