Background: Treprostinil (TRE), a prostacyclin analog, is effective for the treatment of pulmonary arterial hypertension and non-operable and/or non-interventional chronic thromboembolic pulmonary hypertension (CTEPH).  The treatment evidence of TRE in patients with pulmonary hypertension (PH) associated with interstitial lung disease (ILD) is scarce.  We evaluated the safety and efficacy of first-line subcutaneous (sc) TRE in these patients at 1 year on treatment.

Methods: Data was prospectively collected from patients with PH associated with ILD classified in WHO functional class III or IV.  Patients received first-line scTRE.  Dose adjustments were performed individually according to clinical symptoms and side effects.

Results: Between 2007 and 2022, 40 patients (15 patients in WHO functional class III and 25 patients in WHO FC IV) of high-risk profile were treated with first-line scTRE. 
PH-ILD etiology included idiopathic interstitial pneumonia (n=13, 32,5%), combined pulmonary fibrosis and emphysema (n=18, 45%), connective tissue disease (n=5, 12,5%), and occupational lung disease (n=4, 10 %). The mean dose of scTRE was 26.7 ng/kg/min (±12.1 ng/kg/min) 6 months on treatment and 31.9 ng/kg/min (±11.0 ng/kg/min). The side effects profile corresponded to that already observed in studies. None of patients stopped the treatment due to side effects. The risk profile of patients treated with scTRE was significantly improved one year after treatment and less exacerbations of underlying lung disease were observed.  

Conclusion: The risk profile of patients with PH associated with ILD treated with first-line scTRE improved one year after treatment.