Prospects of pirfenidone use in idiopathic pulmonary fibrosis and progressive pulmonary fibrosis

Both idiopathic pulmonary fibrosis (IPF) and progressive pulmonary fibrosis (PPF) are characterized by steady progression, dismal prognosis and high mortality. Antifibrotic therapies such as pirfenidone and nintedanib slow the decline in lung function and improve patient survival, serving as the cornerstone of treatment for IPF. The use of antifibrotics in PPF has been actively explored in recent years. Pirfenidone, with its antifibrotic, anti-inflammatory, and antioxidant properties, inhibits key pathways of fibrogenesis, including TGF-β-mediated mechanisms. This review presents current data on the use of pirfenidone in IPF and PPF, including hypersensitivity pneumonitis, silicosis, and interstitial lung disease associated with connective tissue diseases. The paper reviews the mechanisms of action of pirfenidone, its evidence base (including the results of the pivotal CAPACITY, ASCEND and RELIEF clinical trials) as well as data from real-world clinical practice confirming that pirfenidone slows disease progression and decline in pulmonary function parameters in both IPF and PPF. In a comparative evaluation of pirfenidone and nintedanib, both drugs demonstrate comparable efficacy, but pirfenidone has a more predictable safety profile, with dose-related gastrointestinal disturbances and photosensitization as the most common adverse events. Serious side effects are rarely observed, making pirfenidone a relatively safe treatment option. New therapeutic strategies such as combination with nintedanib, low dose and inhaled forms of the drug are emphasized. Special attention is given to treatment optimization, considering pirfenidone’s safety profile and individual patient characteristics. The prospects for further applications of pirfenidone across different PPF subtypes are discussed.