Inhaled Treprostinil in Participants With Pulmonary Hypertension Due to Chronic Obstructive Pulmonary Disease (PH-COPD)

This is a multi-center, open-label study for eligible participants who completed all scheduled study visits during the Treatment Period of Study RIN-PH-304. Participants who provide informed consent for this open-label extension study on or prior to the final study visit of RIN-PH-304 may participate in the study, provided all other eligibility criteria are met. The RIN-PH-304 final study visit and the RIN-PH-305 Enrollment Visit will occur on the same day. All participants will reinitiate inhaled treprostinil at 3 breathes (18 micrograms \[mcg\]) 4 times daily (QID) during waking hours. Study drug doses should be maximized to tolerability throughout the study, and dose titrations should occur as rapidly as possible (as directed by the Investigator) with a target dosing regimen of 15 breaths QID or the maximum tolerated dose.