5PSQ-100 Comparative analysis of the safety and tolerability profile of pirfenidone and nintedanib in the treatment of idiopathic pulmonary fibrosis

Background and importanceThe main treatments for idiopathic pulmonary fibrosis are pirfenidone and nintedanib. Although their efficacy is known, further studies are needed to evaluate the safety and tolerability profiles (STPs) based on real world data.Aim and objectivesThe aim of this study was to evaluate the STP of nintedanib and pirfenidone according to our hospital data.Material and methodsWe analysed 148 patients treated with pirfenidone (72% men; 28% women) and 120 treated with nintedanib (77% men; 23% women) from September 2016 to September 2019. The average age of the patients treated with pirfenidone and nintedanib was 72.7 and 74.4 years, respectively. Drug tolerability was compared by a Student’s t test considering the average number of days of treatment (DOT) for patients who started the therapy since September 2016 (n=88 pirfenidone; n=120 nintedanib). The safety of the two treatments was compared by analysing the adverse drug reactions (ADRs) reported. ADRs were classified as: nausea/vomiting (NV), diarrhoea, rash, weight loss (WL) and non-specific gastrointestinal disturbance (nsGID). We also considered the type of action taken (interruption, reduction of dosage) and compared the frequencies using a χ² test.ResultsThe Student’s t test showed no statistically significant difference in the average DOT between the two treatments (t=0.9803, df=206, p=0.3281). We detected 30 ADRs in 148 patients treated with pirfenidone (4 of which were severe) and 66 in 120 patients treated with nintedanib (1 severe). Nintedanib showed a greater percentage of ADRs at the gastrointestinal level (NV 18%, diarrhoea 42%, WL 23%, nsGID 39%) compared with pirfenidone (NV 17%, diarrhoea 7%, WL 13%, nsGID 20%). Pirfenidone instead showed a greater percentage of rash (43%) compared with nintedanib (8%). The χ² test carried out on type of action taken showed a statistically significant difference in the distribution of patients who suspended or reduced the dosage for the two drugs (χ² (96)=9.329, p≤0.0023, df=1). Nintedanib showed a higher percentage of patients who reduced the dosage (70%) compared with pirfenidone (37%), probably due to the different dosage titrations. The percentage of patients who suspended therapy was higher for pirfenidone (63%) than for nintedanib (30%).Conclusion and relevanceAlthough the tolerability of the drugs was comparable, nintedanib showed a higher incidence of ADRs compared with pirfenidone but with a lower severity.References and/or ack