Background: It is currently considered that nintedanib slows lung function decline for patients with a progressive fibrotic phenotype(PPF) other than idiopathic pulmonary fibrosis, but the real-world safety and efficacy are not known.

Methods: In this study, data was collected from one centre in Greece and one centre in France, including 35 patients, in whom nintedanib was initiated for PPF. Change in lung function, as well as drug safety and tolerability, during the first year under nintedanib were analysed.

Results:35 patients were included; 21(60%) females, mean age 65(±12) years. At initiation of nintedanib, median FVC was 82%, and DLco 54%pred, while approximately one third of patients displayed usual interstitial pattern on HRCT. 91% of patients were prescribed any immunomodulatory treatment at inclusion. During the first year after drug initiation, there was no significant decline in lung function, although two patients passed away. FVC and DLco was evaluated at 6 months and 12 months (Wilcoxon matched paired test non-significant). The median FVC difference at 12 months was 30ml increase in absolute volume, compared to treatment initiation. The tolerability of the drug was overall well; 18(51.4%) of patients reported side effects, including mostly diarrhea(31.4%). Adverse events led to discontinuation only in 4 patients.

Conclusion: Nintedanib was safe and well tolerated in this real-world study. In regards to efficacy, it stabilized disease progression even in non IPF fibrosis, particularly in CTD-ILD. Importantly, nintedanib did not appear to have excess adverse effects when taken in combination with other immunosuppressants, supporting its role as an add-on treatment in those patients.