Real-World Outcomes of Inhaled Treprostinil in Pulmonary Hypertension Related to Interstitial Lung Disease: A Multicenter, Retrospective Analysis

Inhaled Treprostinil is the primary treatment of pulmonary hypertension related to interstitial lung disease (PH-ILD). Despite treatment effectiveness in clinical trials, the real-world safety and tolerability of this therapy remains unclear. We conducted a multicenter, retrospective review of adults with PH-ILD who were prescribed inhaled treprostinil. We assessed clinical outcomes, 6 min walk distance (6MWD) and changes in natriuretic peptides (BNP, NT-proBNP), as well as medication tolerance. Eighty-three patients met the inclusion criteria. The 6MWD data was collected but a limited number of patients had results within close proximity to initiation of inhalational treprostinil with only seven patients having assessments within the 3 months prior to initiation as well as 3 months post therapy. Limited 6MWD data is likely due, in part, to coinciding with the COVID pandemic, limiting face-to-face interactions and exercise testing. The majority of our subjects, 63%, had an absolute improvement in their BNP level, over a mean duration of 170 days. However, no significant difference was detected between baseline and follow-up natriuretic peptide levels. Adherence was assessed and the majority (77%) of patients remained on therapy at the time of censoring, with three-quarters (75%) meeting the target dose. Of the 15 patients intolerant to nebulized treprostinil who were transitioned to a dry powder inhaler, the majority (87%) were able to tolerate the other formulation. The medication was well-tolerated with a large percentage of patients remaining on therapy indefinitely and reaching the targeted therapeutic dose.