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

Abstract

Background: Pirfenidone 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.

Objective: To investigate the safety and efficacy profile of pirfenidone in IPF patients with severe lung function impairment.

Patients and methods: This was a retrospective study enrolling patients with advanced IPF (FVC%predicted < 50% and/or (DLco%predicted <35%) receiving pirfenidone for at least 6 months.

Results: Between September 2011 and March 2013, we identified 43 patients with severe IPF (baseline meanFVC%predicted±SD: 63.8 ± 20.3, meanDL_CO%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 ΔDL_CO: -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%).

Conclusion: Pirfenidone 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.

Keywords: Efficacy; Idiopathic Pulmonary Fibrosis; Pirfenidone; Safety; Severe.