Overview Study to Assess the Longterm Safety of Sildenafil Citrate in Patients With Pulmonary Arterial Hypertension Status: Completed Trial end date: 2007-02-01 Target enrollment: Participant gender: Summary Open label extension study to the pivotal efficacy study to assess the safety of sildenafil citrate in patients with pulmonary arterial hypertension Phase: Phase 3 Details Lead Sponsor: PfizerPfizer's Upjohn has merged with Mylan to form Viatris Inc.Treatments: Citric AcidSildenafil Citrate