Actelion Pharmaceuticals US, Inc. (United States)

Actelion Pharmaceuticals, now part of Johnson & Johnson’s Janssen Pharmaceutical Companies, specializes in pulmonary arterial hypertension (PAH) treatments. The company pioneered endothelin receptor antagonist therapy with Tracleer (bosentan) and developed Opsumit (macitentan) and Uptravi (selexipag) for PAH. Actelion’s expertise in rare cardiovascular diseases has helped transform treatment outcomes for patients with life-threatening pulmonary hypertension conditions.