Effect of low dose pirfenidone on survival and lung function decline in patients with idiopathic pulmonary fibrosis (IPF): results from a real life study

Abstract

<b>Background:</b> Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic and progressive fibrosing interstitial pneumonia of unknown cause. In many randomized clinical trials and in real-world experiences, pirfenidone has been proven to be effective and safe in the treatment of IPF. The aim of this study was to evaluate the efficacy of relatively lower dose of pirfenidone on disease progression and survival of IPF patients in real-world. <b>Methods:</b> This is a retrospective observational study based on IPF cohort in which IPF patients were enrolled at the time of diagnosis at a single center from 2008 to 2018.&nbsp;We compared the clinical characteristics, overall survival and decline of pulmonary function of the patients treated with variable dose of pirfenidone with patients not treated with pirfenidone. <b>Results:</b> Of the total 295 patients with IPF, 100 (33.9%) received pirfenidone and 195 (66.1%) were not prescribed antifibrotic agents.&nbsp;Of the 100 patients who received pirfenidone, 24% (24/100), 50% (50/100), and 26% (26/100) were given 600mg, 1200mg, and 1800mg of pirfenidone, respectively. Mean survival time was 57.03±3.90 months in the no-antifibrotic drug group, 73.26±7.87 months in the pirfenidone-treated group, and significantly longer in the pirfenidone-treated group (p=0.027).&nbsp;In the analysis of pulmonary function, the decline in FVC (%), FEV1 (%) and DLCO (%) was significantly lower (p=0.000, p=0.001 and p=0.007, respectively) in the group using pirfenidone compared to the group not using it. <b>Conclusions:</b> Low dose pirfenidone provided beneficial effects on survival and pulmonary function decline in real life practice.