Antifibrotic treatment in progressive non-IPF fibrotic interstitial lung diseases

Introduction and Aim: Pirfenidone and nintedanib are anti-fibrotic approved treatments for idiopathic pulmonary fibrosis (IPF). Its efficacy and safety in other fibrotic interstitial lung diseases (ILD) is under study in clinical trials. The aim was to analyse the effect of these drugs in non-IPF progressive fibrotic patients that couldn’t be included in these trials. Methods: Multicenter retrospective study of 34 progressive PF non-IPF patients treated with anti-fibrotic drugs. Demographic, clinical data and treatment-related variables were evaluated. The reason to start off-label anti-fibrotic was disease progression with previous therapy and exclusion from clinical trials. Results: Patients with non-IPF progressive PF were: 38% unclassifiable PF (UPF), 20% familial pulmonary fibrosis (FPF), 18% CTD-ILD, 15% chronic hypersensitivity pneumonitis (CHP) and 9% pneumoconiosis. Mean age was 67±12 years, 74% were male and 47% ex-smokers. 21% of cases had usual interstitial pneumonia HRCT pattern. Mean FVC was 66%±23 and DLCO 45%±12. Co-medications were: low-dose prednisone (20), mycophenolate (5) and sirolimus (1). Twenty-four subjects (71%) received pirfenidone and ten (29%) nintedanib. After one year, a FVC decrease of 5-10% was observed in only 3 patients (1 CHP, 1 pneumoconiosis, 1 UPF), while others showed stability or improvement. Main reported adverse effects were: 20% hypertransaminasemia, 27% diarrhea and 15% weight loss, requiring 5 patients to stop therapy. Conclusion: After one year of anti-fibrotic therapy, most patients with non-IPF progressive PF showed functional stability. Clinical trials are mandatory to evaluate their potential efficacy, but these drugs are a safe option in progressive PF patients.