<unk> , sold under the brand name Opsumit, is an endothelin receptor antagonist (ERA) developed by Actelion and approved for the treatment of pulmonary arterial hypertension (PAH). The other two ERAs marketed as of 2014 are bosentan and ambrisentan.<unk>  is a dual ERA, meaning that it acts as an antagonist of two endothelin (ET) receptor subtypes, ETA and ETB. However,<unk>  has a 50-fold increased selectivity for the ETA subtype compared to the ETB subtype. The drug received approval from the U.S. Food and Drug Administration (FDA) on October 13, 2013.<unk>  is available as a generic medication in the United States as of April 2021.
Macitentan
Bosentan
Sitaxentan
Ambrisentan
Darusentan
Sildenafil
Telmisartan
Vericiguat