Anti-fibrotic Agents in Progressive Fibrosing Interstitial Lung Diseases: A Systematic Review

Abstract

Introduction: Progressive fibrosing interstitial lung disease (PF-ILD) is a phenotype characterized by worsening fibrosis and lung function decline, occurring across various ILD subtypes. Anti-fibrotic agents, nintedanib and pirfenidone, are approved for idiopathic pulmonary fibrosis (IPF). This review evaluates their efficacy in non-IPF PF-ILDs.

Methods: We searched for placebo-controlled RCTs of nintedanib or pirfenidone in patients with a diagnosis of a PF-ILD other than IPF. The primary outcome was the annual rate of decline in forced vital capacity (FVC).

Results: The review was dominated by a single large RCT of nintedanib. This trial showed that nintedanib significantly slowed the rate of FVC decline by approximately 57% compared to placebo in patients with a broad range of PF-ILDs. Gastrointestinal side effects were common but manageable.

Discussion: The findings support the concept of a common fibrotic pathobiology across different ILDs. Nintedanib appears to be an effective treatment for slowing disease progression in the progressive fibrosing phenotype, regardless of the underlying ILD diagnosis.

Conclusion: Nintedanib significantly slows the progression of lung function decline in patients with progressive fibrosing interstitial lung diseases.