Summary of pirfenidone and nintedanib trials conducted in progressive fibrosing interstitial lung diseases (PFILDs)
| PFILD (non-IPF) | Trial | Nintedanib/pirfenidone |
| PFILD (CTD-ILD; fHP; autoimmune lung fibrosis; NSIP; unclassifiable IIP; sarcoidosis; others) | INBUILD [8] | Nintedanib |
| PFILD (CTD-ILD; NSIP; fHP; asbestosis) | RELIEF [7] | Pirfenidone |
| Sarcoidosis PFILD | PirFS [32] | Pirfenidone |
| Unclassifiable PFILD | Pirfenidone in unclassifiable PF-ILD [33] | Pirfenidone |
| Pneumoconiosis PFILD | NiPPS (ClinicalTrials.gov identifier: NCT04161014, expected completion 2025) | Pirfenidone |
| Pulmonary fibrosis with anti- myeloperoxidase antibodies PFILD | PIRFENIVAS [34] | Pirfenidone |
IPF: idiopathic pulmonary fibrosis; CTD-ILD: connective tissue disease associated ILD; NSIP: nonspecific interstitial pneumonia; fHP: fibrosing hypersensitivity pneumonitis; IIP: idiopathic interstitial pneumonia; INBUILD: Efficacy and Safety of Nintedanib in Patients With Progressive Fibrosing Interstitial Lung Disease; RELIEF: Exploring Efficacy and Safety of oral Pirfenidone for progressive, non-IPF Lung Fibrosis; PirFS: Pirfenidone for Progressive Fibrotic Sarcoidosis; NiPPS: The Nintedanib in Progressive Pneumoconiosis Study; PIRFENIVAS: Pilot Study of Pirfenidone in Pulmonary Fibrosis with Anti-myeloperoxidase Antibodies. Notable fibrosing ILD trials, excluded due to lack of progression in inclusion criteria, include the TRAIL 1 (Pirfenidone in rheumatoid arthritis associated ILD) and SENSCIS trials (Nintedanib in systemic sclerosis associated ILD) [35, 36].