Early Experience of Pirfenidone in Daily Clinical Practice in Belgium and The Netherlands: a Retrospective Cohort Analysis

INTRODUCTION: This analysis aimed to investigate the effectiveness and safety profile of pirfenidone for the treatment of idiopathic pulmonary fibrosis (IPF) in clinical practice. METHODS: Clinical records of patients diagnosed with mild-to-moderate IPF (as per European Medicines Agency indication) and receiving pirfenidone treatment across three centers in Belgium and the Netherlands between April 2011 and October 2013 were retrospectively collected from patient notes at 3-month intervals. Pulmonary function measurements, including % predicted forced vital capacity (%FVC) and % predicted diffusing capacity of the lungs for carbon monoxide (%DLCO), were analyzed from 6 months prior to pirfenidone treatment up to 12 months of treatment. Decline in lung function, defined as an absolute ≥10% decline in FVC from baseline or death at 12 months, was also analyzed. Safety data were included for all follow-up visits. RESULTS: In the pooled cohort (n = 63), patients were mostly men (84.1%) and current or former smokers (79.4%). Average baseline %FVC and %DLCO were 75.0% and 47.9%, respectively. 69.8% of patients had a high-resolution computed tomography scan with a definite usual interstitial pneumonia pattern, and 46% had a surgical lung biopsy. The mean decline in %FVC for 32 patients with available data was 4.8% from -6 months to baseline (p = 0.002) and 0.8% from baseline to 6 months (p = 0.516). Across these time intervals, a lesser decline in DLCO was similarly observed during therapy. At 12 months, ten patients had an %FVC decline ≥10% or died. Loss of appetite (25.3%) and nausea (11.1%) were the most frequent gastrointestinal side effects. Nausea was the most highly cited reason for discontinuation (7.9%). CONCLUSIONS: In this clinical practice cohort, pirfenidone showed effectiveness and safety profiles consistent with those seen in the Phase III clinical study ASCEND (ClinicalTrials.gov #NCT01366209). These results highlight the challenges and benefits associated with pirfenidone treatment in clinical practice.