Oral Treprostinil in Subjects With Pulmonary Hypertension Associated With Pulmonary Fibrosis

Inclusion Criteria: * Voluntarily gives informed consent * Must meet criteria for lung transplant referral but is not required to be on an active lung transplant list * Stable and significant diffuse parenchymal lung disease with a diagnosis of interstitial lung disease * 6MWD greater than or equal to 75 meters * Right heart catheterization with a mean pulmonary arterial pressure \>= 30 mgHg, pulmonary capillary wedge pressure \<= 15 mmHg and pulmonary vascular resistance \> 240 dynes * Echo-Doppler examination showing evidence of right ventricular dysfunction and normal left diastolic ventricular function * Either not receiving any PAH-approved oral therapy, or is receiving monotherapy (ERA, PDE-5I, or riociguat) for \> 60 days and receiving a stable dose for \> 30 days prior to enrollment * Able to communicate effectively with study personnel and will to be cooperative with protocol requirements Exclusion Criteria: * History of repaired or unrepaired congenital heart disease * Received prostanoid therapy in the past 30 days, or has shown an intolerance or lack of efficacy to prostanoid therapy resulting in discontinuation or inability to titrate prostacyclins * Diagnosis of sarcoidosis * History of thromboembolic disease * Chronic renal insufficiency * Pregnancy or lactating * Currently receiving an investigational drug, has an investigational device in place, or has participated in an investigational drug or device study within 30 days prior to Screening