<unk>  (U.S. trade name Letairis; E.U. trade name Volibris; India trade name Pulmonext by MSN labs) is a drug indicated for use in the treatment of pulmonary hypertension. The peptide endothelin constricts muscles in blood vessels, increasing blood pressure.<unk> , which relaxes those muscles, is an endothelin receptor antagonist, and is selective for the type A endothelin receptor (ETA).<unk>  significantly improved exercise capacity (6-minute walk distance) compared with placebo in two double-blind, multicenter trials (ARIES-1 and ARIES-2). Like all endothelin receptor antagonists,<unk>  is contraindicated in pregnant women as well as those who are trying to become pregnant, due to the potential for teratogenic effects on the fetus. Patients who are on the<unk>  must enroll in the<unk>  (Letairis) REMS Program.<unk>  was approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), and designated an orphan drug, for the treatment of pulmonary hypertension.
Ambrisentan
Bosentan
Macitentan
Sitaxentan
Darusentan
Vericiguat
Spirapril
Nitroxinil