Pirfenidone and nintedanib for pulmonary fibrosis in clinical practice: Tolerability and adverse drug reactions

Background and objective The real-world tolerability of pirfenidone and nintedanib in non-clinical trial patients is unknown. Many patients with pulmonary fibrosis have significant medical co-morbidities or baseline characteristics that exclude them from clinical trial participation. Methods We conducted a retrospective chart review study on subjects prescribed nintedanib or pirfenidone for pulmonary fibrosis treatment (any aetiology) from September 2014 to February 2016. A total of 186 subjects were included: 129 received pirfenidone and 57 were prescribed nintedanib and followed up for mean observation periods of 52 ± 17 weeks for pirfenidone and 41 ± 15 weeks for nintedanib. The primary outcome was drug discontinuation as a result of an adverse event. Results Subjects had significant respiratory impairment at baseline, 63% required home oxygen therapy and mean diffusion capacity of carbon monoxide (DLCO) was 36 ± 14% predicted. Drug discontinuation as a result of an adverse event occurred in 20.9% of subjects on pirfenidone and 26.3% on nintedanib. Drug discontinuation rates for both pirfenidone and nintedanib did not significantly differ from corresponding large clinical trials (ASCEND/CAPACITY and INPULSIS 1 and 2, respectively). Adverse events that occurred with highest frequency on pirfenidone were nausea (26.4%), rash/photosensitivity (14.7%) and dyspepsia/gastroesophageal reflux disease (GERD) (12.4%). Diarrhoea (52.6%) and nausea (29.8%) were reported most often with nintedanib therapy. Conclusion Patients with pulmonary fibrosis treated with nintedanib or pirfenidone in routine clinical practice had drug tolerability and adverse event profiles comparable with subjects enrolled in clinical trials despite having a greater degree of respiratory impairment and a high prevalence of co-morbid medical conditions.