Background and Importance Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease characterised by a bad prognosis. The only available pharmacological treatments are two antifibrotic drugs, pirfenidone and nintedanib, which slow down the development of the disease but have an unfavourable safety profile, with a high incidence of adverse effects.

Aim and Objectives To compare the effectiveness and safety of the two available antifibrotic drugs, nintedanib and pirfenidone, used as treatment of idiopathic pulmonary fibrosis.

Material and Methods Retrospective, observational and descriptive study of all the patients diagnosed with idiopathic pulmonary fibrosis treated with pirfenidone or nintedanib between January 2014 and February 2022. The collected variables were: age, sex, forced vital capacity (FVC), duration of treatment, adverse effects (AE) and grade, and survival. Patient confidentiality was preserved throughout the data gathering.

Results 41 patients, 30 of them men, were included. 24 treated with nintedanib and 17 with pirfenidone, both groups had a median age of 73 years old (range 54-89).

Average difference from basal FVC was +4,82% at 6 months, + 1,85% at 12m, +1,85% at 16m and -6,25% at 24m with nintedanib and +2,4% at 6m, -5,5% at 12m, -5,5% at 16m and -18,5% at 24m with pirfenidone.

Median duration of treatment was 26 months with nintedanib and 45 months with pirfenidone. Overall survival was 65 months (CI 95% 57.5-73.9) on average for nintedanib and 33 months (CI 95% 23.4-42.5) for pirfenidone (log-rank p=0.009).

Treatment was poorly tolerated, with a high incidence of AE (nintedanib: no AE: 21%, G1: 4%, G2: 42%, G3: 29%, G4: 4%; pirfenidone no AE: 53%, G1: 12%, G2: 29%, G3: 6%). Most frequent AE was gastrointestinal reactions in 17 (71%) with nintedanib and 6 (35%) with pirfenidone, followed by headache in 3 (13%) with nintedanib and 4 (24%) with pirfenidone, hepatic enzyme alteration in 5 (21%) with nintedanib, dermatological 4 (17%) nintedanib, renal toxicity in 2 (8%) with nintedanib, haematological 1 (4%) with nintedanib.

AE caused the discontinuation of treatment in 11 (46%) patients with nintedanib and in 4 (24%) with pirfenidone.

Conclusion and Relevance Nintedanib was significantly more effective in terms of overall survival, with a slower decrease in FVC, although presented worse tolerance than pirfenidone, as treatment of IPF.

Conflict of Interest No conflict of interest