Antifibrotic Therapy in Fibrosing Interstitial Lung Disease: A Retrospective Analysis at a Tertiary Referral Institution
Year: 2021
Type: conference-abstract
Abstract: Rationale: Antifibrotic drugs are recommended for idiopathic pulmonary fibrosis (IPF) to reduce the rate of disease progression. Treatment options for non-IPF fibrotic interstitial lung disease (ILD) are limited. IPF and some non-IPF ILD have overlapping pathophysiology and share similar clinical courses. Nintedanib is the first FDA-approved drug for progressive fibrotic phenotypes of non-IPF ILD. Multiple ongoing clinical studies are investigating indications of antifibrotic therapy in different types of non-IPF ILD. We reviewed pirfenidone and nintedanib use at our institution. Methods: Patients with ILD who received antifibrotic therapy at a tertiary referral institution from January 2014 to October 2019 were retrospectively reviewed. Results: We identified 123 ILD patients receiving pirfenidone (57, 46%), nintedanib (50, 41%), or both (16, 13%) when switching from one drug to the other. All patients were reviewed and reclassified based on correlation of clinical, radiological, and histopathologic findings. The most common diagnosis was IPF (83, 67.5%). Non-IPF conditions included unclassifiable ILD (12, 9.8%), connective tissue disease-related ILD (10, 8.1%), combined pulmonary fibrosis and emphysema (7, 5.7%), interstitial pneumonia with autoimmune features (6, 4.9%), chronic hypersensitivity pneumonitis (4, 3.3%), and Hermansky-Pudlak syndrome (1, 0.8%). Mean age was 71 8.02 years. Most patients were male (74%) and former smokers (66%). Average forced vital capacity (FVC) and diffusing capacity for carbon monoxide were 65 16.7% (range 31-133%) and 41 14.1% (range 17-76%), respectively. Available spirometry in non-IPF conditions before and after antifibrotic therapy failed to show significance due to small sample size; mean annual change in FVC before and after nintedanib was -388.3 ml and -57.3 ml (n=12, p=0.17); mean annual change in FVC before and after pirfenidone was -134.2 ml and -472.2 ml (n=6, p=0.51). Chest CT patterns included definite usual interstitial pneumonia (UIP, 64, 52%), probable UIP (42, 34%), indeterminate (16, 13%) and non-UIP (1, 0.8%). The overall mortality rate was 43%. Non-IPF ILD had a higher mortality rate than IPF (60% vs. 34%, p=0.006) possibly due to more severe disease at initial evaluation. There was no difference in the mortality rate between pirfenidone and nintedanib treatment (p=0.43). Switching from one drug to the other was not associated with mortality (p=0.55). Conclusions: Among 123 patients treated with antifibrotic therapy, 32.5% had non-IPF ILD. Antifibrotic agents were considered prior to FDA approval. Only nintedanib suggested a trend in slowing disease progression but limited data precluded statistical significance. Further study of antifibrotic therapy in non-IPF ILD is warranted.
Authors: V.S.R. Koppurapu, Y. Zemkova, D. Barber, K.M. Shin, A. Laroia, C.H. Lee, K. Ussavarungsi
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4252010574