Assess the Efficacy and Safety of Sildenafil When Added to Bosentan in the Treatment of Pulmonary Arterial Hypertension

Phase 4 Completed 105 enrolled Viatris Inc.

RandomizedParallel-groupQuadruple-blindTreatment

To assess the efficacy and safety of sildenafil when added to patients with PAH who are taking bosentan as all or part of their background therapy.

Evaluation	Drug	Modality	Dose	Route
Subject	Sildenafil	Unknown	20 mg	Oral
Background	Bosentan	Other / unclassified	62.5 mg	—
Background	Bosentan	Other / unclassified	125 mg	—