- Has a current diagnosis of symptomatic PAH
- Has 6MWT distances from 150 to 450 meters and distance
- Previous exposure to an endothelin receptor antagonist
- Has uncontrolled systemic hypertension as evidenced by sitting systolic blood pressure
>160 mm Hg or sitting diastolic blood pressure >100 mm Hg at Screening.
- Has hypotension defined as systolic arterial pressure minutes at Screening.