A Study to Assess Pulsed Inhaled Nitric Oxide in Subjects With Pulmonary Fibrosis at Risk for Pulmonary Hypertension

Inclusion criteria: * A high resolution CT scan performed in the 6 months prior to screening associated with one of the following conditions and confirmed using guidelines, as per American Thoracic Society (ATS) / European Respiratory Society (ERS) / Japanese Respiratory Society (JRS) / Latin American Thoracic Association (ALAT): * Major IIPs (idiopathic interstitial pneumonias) diagnosis or suspected as one of the following: * Idiopathic pulmonary fibrosis * Idiopathic nonspecific interstitial pneumonia * Respiratory bronchiolitis-interstitial lung disease * Desquamative interstitial pneumonia * Cryptogenic organizing pneumonia * Acute interstitial pneumonia * Rare IIPs diagnosis by one of the following: * Idiopathic lymphoid interstitial pneumonia * Idiopathic pleuroparenchymal fibroelastosis * Unclassifiable idiopathic interstitial pneumonias * Chronic hypersensitivity pneumonitis * Occupational lung disease * Connective Tissue Disease associated with IPF (CTD-ILD) * Interstitial Pneumonia with Autoimmune Features (IPAF) * Have been using oxygen therapy by nasal cannula for at least 4 weeks (including use limited to exertion) * 6MWD ≥ 100 meters and ≤ 400 meters at screening and Baseline/Randomization visits. * World Health Organization (WHO) Functional Class II-IV * Forced Vital Capacity ≥ 40% predicted within the 60 day Screening period * Age between 18 and 80 years (inclusive) at screening Exclusion criteria: * Fo…