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.