Short-Term Effectiveness of Antifibrotics in Idiopathic Pulmonary Fibrosis

Patients taking the antifibrotic medications nintedanib and pirfenidone for idiopathic pulmonary fibrosis (IPF) had reduced all-cause mortality and hospitalizations for up to 2 years compared with a matched untreated cohort, according to a study published in the American Journal of Respiratory and Critical Care Medicine.

This real-world, retrospective cohort analysis used a large US insurance database to identify 8098 patients with IPF, who were then propensity-score matched 1:1 to compare patients treated with the antifibrotic medications nintedanib and pirfenidone (n=1255) with untreated patients (n=1255). The primary study end point was all-cause mortality, with a secondary end point of acute hospitalizations. Mortality differences by drug were evaluated using subgroup analysis.

The use of both antifibrotic medications was associated with a decreased all-cause mortality risk (treated vs untreated cohorts: 13.78 per 100 person-years vs 16.34 per 100 person-years; hazard ratio [HR], 0.77; 95% CI, 0.62-0.98; P =.034). However, this association only persisted through the initial 2 years of treatment. The treated cohort also showed a decreased acute hospitalization risk (46.70 per 100 person-years vs 62.44 per 100 person-years; HR, 0.70; 95% CI, 0.61-0.80; P <.001). No significant difference was observed in all-cause mortality between patients taking pirfenidone compared with those taking nintedanib (pirfenidone: 12.83 per 100 person-years vs nintedanib: 14.77 per 100 person-years; HR, 1.14; 95% CI, 0.79-1.65; P =.471). Sensitivity analyses to confirm findings all showed similar results to the primary findings.

Limitations of this study included the dataset, which was limited to individuals enrolled in private and Medicare Advantage health plans with pharmaceutical benefits; possible confounding factors; and the researchers’ inability to confirm whether participants were taking medications as intended throughout the study period.

Study investigators concluded, “Compared head-to-head, there was no difference in all-cause mortality between the medications. Further research is needed to test the hypothesis that these treatments reduce early but not long-term mortality as demonstrated in our study.”

Reference

Dempsey TM, Sangaralingham LR, Yao X, Sanghavi D, Shah ND, Limper AH. Clinical effectiveness of the anti-fibrotic medications for idiopathic pulmonary fibrosis [published online May 31, 2019]. Am J Respir Crit Care Med. doi:10.1164/rccm.201902-0456OC