Nintedanib for progressive pulmonary fibrosis in real-world setting: an observational study comparing outcomes with an IPF cohort

Introduction: Progressive Pulmonary Fibrosis (PPF) includes various fibrosing ILDs evolving similarly to Idiopathic Pulmonary Fibrosis (IPF). Nintedanib, previously approved for IPF, showed antifibrotic efficacy in PPF, but real-world data remain limited. This retrospective study investigated the real-world effectiveness of nintedanib in PPF compared to IPF, focusing on PFTs trends, tolerability, and impact of concomitant therapies. Methods: Data were retrospectively collected from an Italian referral centre (March 2021–August 2024). Study cohort met PPF classification criteria, while consecutive IPF patients were enrolled as control group. Lung function data at baseline, 12-months pre- and 12-month post-treatment were analysed using Linear Mixed Models. Adverse events and dose adjustments were recorded to assess safety. Results: Eighty-two PPF patients and 85 with IPF were included. At treatment initiation, the PPF group had significantly lower FVC (2.04 L vs 2.63 L; p < 0.001) and DLCO (46.41% vs 55.98%; p = 0.002), indicating more advanced disease. Nintedanib significantly reduced PPF cohort’s FVC decline (–141.40 mL before treatment then –20.36 mL; p < 0.001). A sub-analysis in PPF patient with radiological UIP/UIPp pattern revealed an increased efficacy of antifibrotic treatment. Although IPF group had better baseline condition, they showed higher rate of lung function decline. Most PPF patients (81.7%) received concurrently immunomodulatory drugs. Adverse events were primarily gastrointestinal in both groups, with similar incidence of dose reductions and treatment discontinuation. Conclusion: In a real-world setting, nintedanib significantly slowed disease progression in PPF patients, mirroring outcomes and tolerability profile demonstrated in IPF. Further large-scale, prospective studies are needed to understand how to optimize antifibrotic therapy for PPF.