Zurkova M, et al. - Researchers tested the impact of pirfenidone, an antifibrotic drug, on the decline of lung function and overall survival (OS) in a real-world cohort of 841 patients from the Czech EMPIRE (European MultiPartner IPF Registry). Pirfenidone and no-antifibrotic treatment were administered to 383 (45.5%) and 218 (25.9%) patients, respectively, and 240 (28.5%) were excluded (missing data, nintedanib treatment). Participants were assessed at treatment initiation and at 6, 12, 18 and 24 months follow-up. As evaluated by the decline of ≥10% forced vital capacity (FVC) (17.0%) and ≥ 15% diffusing lung capacity for carbon monoxide (DL_CO) (14.3%), progression was seen in less than a quarter of the patients on pirfenidone, as seen during a 2-yr follow-up. In patients treated with pirfenidone, increased mortality was noted in association with the DL_CO (≥10%) declines observed at 6, 12, 18 and 24 months’ and DL_CO (≥15%) declines seen at 6, 18 and 24 months’ follow-up. Compared to FVC decline, a higher predictive value for mortality was shown by the DL_CO decline. Mortality was not predicted by FVC and DL_CO declines in patients with no-antifibrotics. Increased 5-yrs OS was achieved with pirfenidone over no-antifibrotic treatment (55.9% vs 31.5% alive).