Safety and efficacy of pirfenidone in severe Idiopathic Pulmonary Fibrosis: A real-world observational study

BackgroundPirfenidone is a novel anti-fibrotic drug that has shown efficacy in five randomized multicenter clinical trials enrolling patients with Idiopathic Pulmonary Fibrosis of mild-to-moderate disease severity. Scarce data supports the use of pirfenidone in IPF patients with more advanced disease.ObjectiveTo investigate the safety and efficacy profile of pirfenidone in IPF patients with severe lung function impairment.Patients and methodsThis was a retrospective study enrolling patients with advanced IPF (FVC%predicted < 50% and/or (DLco%predicted <35%) receiving pirfenidone for at least 6 months.ResultsBetween September 2011 and March 2013, we identified 43 patients with severe IPF (baseline meanFVC%predicted±SD: 63.8 ± 20.3, meanDLCO%predicted: 27.3 ± 8.2), of mean age±SD: 66.3 + 9.7, 34 males (81%) that received pirfenidone (2.403 mg/daily) for one year. Pirfenidone treatment was associated with a trend towards decrease in functional decline compared to 6-months before treatment initiation but failed to show any benefit after one year of treatment (ΔFVC: −3.3 ± 4.6 vs 0.49 ± 11.4 and vs. −5.8 ± 11.8, p = 0.06 and p = 0.04, respectively and ΔDLCO: −13.3 ± 15.2 vs. −10.1 ± 16.6 and vs. 28.3 ± 19.2, p = 0.39 and p = 0.002, respectively). Gastrointestinal disorders (34.9%), fatigue (23.2%) and photosensitivity (18.6%) were the most common adverse events. Adverse events led to treatment discontinuation in 9 patients (20.9%) and dose reduction in 14 (32.5%).ConclusionPirfenidone appears to be safe when administered in patients with advanced IPF. Pirfenidone efficacy in IPF patients with severe lung function impairment may diminish after 6 months of treatment.