Background. Nintedanib treatment(NT) has recently become available in Italy for progressive fibrosing interstitial lung disease(PF-ILD). Results of clinical trials need to be confirmed in a real-world setting.

Aim. To assess the safety, applicability and efficacy of NT in a real-life cohort of PF-ILD. To look for serum signals of response to NT.

Method. All the consecutive patients (Jul?20/Oct?22) with ILD (not IPF) and PF-ILD criteria (INBUILD) were reviewed for NT. The following data are collected before and 3, 6 months after starting NT: pulmonary function tests, drug-related adverse events, CBC and liver function. Blood samples were stored for biomarkers investigations (igf-bp2, wnt4, ccl-18, pentraxin family, galactine family).

Results. Overall 46/110 patients (42%) had PF-ILD criteria (32/110 connective tissue disease-ILD) and among these 46 patients, 14 (30%) met NT criteria. Mean follow-up NT was 2,5 ± 0,7 months. Fibrotic progression was associated with a lower baseline value of FVC% and DLCO% (p= 0,005) and the presence of UIP/UIP probable pattern (p= 0,005) but not with the presence of comorbidities. At 3-months follow-up we observed a not significant decline in FVC and 6 minute walking test (87.5 ml and 15.7 meters); 11/14 (79%) of patients developed drug-related adverse events leading to a temporary suspension or to a dose reduction in 57% and 36% of them; no one stopped permanently the NT. Main adverse events were nausea, vomiting and increased transaminase levels. Six months follow-up results and biomarkers will be presented.

Conclusion. Three months NT in selected PF-ILD seems to stabilize functional decline in PF-ILD with acceptable toxicity profile.