A Study to Evaluate the Efficacy and Safety of Once Daily Treprostinil Palmitil Inhalation Powder (TPIP) in Participants With Pulmonary Arterial Hypertension (PAH)

Inclusion Criteria * Participants must have a diagnosis of World Health Organisation (WHO) Group 1 pulmonary hypertension (PAH) in any of the following subtypes, in accordance with European Society of Cardiology European Respiratory Society (ESC/ERS) Guidelines: * Idiopathic PAH * Heritable PAH * Drug/toxin-induced PAH * Connective tissue disease (CTD)-associated PAH * PAH associated with congenital heart disease-related to simple systemic-to-pulmonary shunt at least 1 year following repair. * PAH diagnosis for at least 3 months prior to Screening. * New York Heart Association (NYHA) or World Health Organization (WHO) functional class II-IV. * Participants must be on stable PAH therapy consisting of 1 to 3 medications from the following classes: * Endothelin receptor antagonists (eg, ambrisentan, bosentan, macitentan) for at least 90 days prior to Screening with the last 30 days on stable dose. * Phosphodiesterase type 5 inhibitors (eg, sildenafil, tadalafil) for at least 90 days prior to Screening with the last 30 days on stable dose * Guanylate cyclase stimulator (eg, riociguat) for at least 90 days prior to Screening with the last 30 days on stable dose * Activin signaling inhibitor (e.g., sotatercept) for at least 6 months prior to Screening, with the last 3 months on stable dose and meeting all the following conditions: * no active clinically significant bleeding (eg, epistaxis and gingival bleeding requiring medical interventions) within the pa…