Rapid Inpatient Uptitration of Inhaled Treprostinil in PH-ILD Patients with Severe Phenotype

Pulmonary hypertension associated with interstitial lung disease (PH-ILD) is a progressive condition with limited treatment options and associated with high mortality rates. Inhaled treprostinil (iTre) is the only approved therapy for PH-ILD and has been shown to improve exercise capacity and delay disease progression. However, the conventional outpatient titration schedule requires 8–16 weeks to achieve therapeutic dosing, which may delay clinical benefit in those with advanced disease. We conducted a retrospective study of six patients with severe PH-ILD admitted to a tertiary academic center for initiation of iTre using a rapid inpatient uptitration protocol. iTre was started at 3 breaths four times daily (QID) and increased by 2 additional breaths every 12–24 h as tolerated, aiming for ≥9–12 breaths QID within one week under close monitoring. All six patients achieved target dosing without dose reduction or interruption. At three-month follow-up, mean pulmonary artery pressure decreased from 42 ± 5.5 to 35.2 ± 4.5 mmHg, pulmonary vascular resistance from 8.0 ± 1.2 to 6.0 ± 0.9 WU, and cardiac index increased from 2.05 ± 0.13 to 2.15 ± 0.12 L/min/m2. No readmissions occurred within 90 days. This study demonstrates that rapid inpatient uptitration of iTre in severe PH-ILD is feasible and well-tolerated, with preliminary evidence of short-term hemodynamic improvement.