A Transition Study From Flolan® to Remodulin® in Patients With Pulmonary Arterial Hypertension

This trial is a multicenter, randomized, parallel placebo-controlled study of Remodulin in patients with pulmonary arterial hypertension with WHO Functional Class II or III clinical status who have been transitioned from Flolan therapy. The study consists of Screening, Baseline and Treatment Phases. Patients meeting all inclusion/exclusion criteria during the Screening Phase will enter the Baseline Phase, during which baseline exercise capacity, vital signs, and clinical signs and symptoms of the disease will be assessed. After confirmation of all inclusion/exclusion criteria, patients will be randomized to study drug (1:1 Remodulin:placebo) and will enter the Treatment Phase. The Treatment Phase begins with a Dose Transition Period, during which patients will begin receiving subcutaneous study drug at a low dose determined by the patient's current dose of Flolan. The study drug dose will be increased gradually while the Flolan dose is decreased gradually over a period of up to 14 days. The dose changes will be done according to a recommended schedule, which may be modified if necessary according to the patient's clinical status. The dose changes will continue until Flolan therapy has been discontinued and the patient is stable on study drug, or until the patient has met the primary endpoint criteria. Patients who are transitioned off Flolan, who are stable on study drug, and who have demonstrated the ability to properly self-administer study drug will be discharged from the clinic, and will continue to receive study drug on an outpatient basis. The patient will return to the clinic at Weeks 4 and 8 for assessments. At weeks other than Weeks 1, 4, and 8, the site staff will contact the patient to assess progress and adjust the study drug dose if necessary. Patients will remain on study drug for 8 weeks from the first dose of study drug. At Week 8, final assessments will be conducted and the patient will be dismissed from the study. Patients who successfully complete Week 8 assessments may be offered Remodulin therapy or other therapy, at the investigator's discretion.