M14 Has antifibrotic therapy altered outcomes in patients with idiopathic pulmonary fibrosis? A real world analysis

Introduction Pirfenidone and nintedanib are the only disease-modifying treatments available for idiopathic pulmonary fibrosis (IPF). Clinical trials have demonstrated a disease-stabilising effect of these medications in controlled conditions. Our aim was to test their efficacy, tolerability and safety in routine clinical practice. Methods Data was collected retrospectively on patients with IPF seen in the ILD MDT between 2011–2017. This included patients treated with antifibrotics and those untreated, but with an FVC% predicted in the treatment range (control patients). Variables collected from the electronic patient records included demographics, lung function, survival, progression-free survival (PFS) – progression defined as 10% reduction in FVC or death – and drug tolerability outcomes including discontinuations. Results Of 104 patients prescribed antifibrotics, 54 received pirfenidone only, 36 received nintedanib only and 14 received both. There were 64 control patients. The 365-day mortality rate was 25.3% for the antifibrotic group and 35.5% for the control group (p=0.169). PFS at 6 months was significantly improved in the antifibrotic group (73.7%) compared to the control group (54.8%) (p=0.015). At 12 months, PFS was improved in the antifibrotic group (49.5% in the antifibrotic group and 37.1% in the control group), although the result was not statistically significant (p=0.127). The 12-month post-treatment mean decline in FVC% predicted (4.8±6.7%) was significantly less than the 12-month pre-treatment decline (11.7±12.2%) (p=0.041). Antifibrotic discontinuation by 3 months was significantly higher for patients on pirfenidone (31.7%) than those on nintedanib (11.4%) (p=0.026). By 12 months, discontinuation was higher in the pirfenidone group (48.3%) than the nintedanib group (40%) but the difference was not statistically significant (p=0.431). The 365-day mortality rate for the antifibrotic group, excluding patients who discontinued treatment within 3 months, was 20.3% and the difference between this and the control group (35.5%) was statistically significant (p=0.043). Conclusion Promising results were shown for mortality, PFS and lung function for patients on antifibrotics, although this data may favour commencement of nintedanib as first line therapy, given the lower rates of treatment discontinuation by 3 months. Patients who were able to tolerate antifibrotic therapy for the first 3 months were shown to have a significantly improved mortality.