EC Pulmonology and Respiratory Medicine

As a clinically important fibrotic phenotype, Progressive pulmonary fibrosis (PPF) occurs across a heterogeneous group of interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF). Despite appropriate management, PPF is characterised by physiological deterioration, worsening respiratory symptoms, and radiographic progression usually accompanied by significant morbidity and mortality. The recognition that pulmonary fibrosis may progress irrespective of its underlying diagnostic category has led to increasing interest in early antifibrotic treatment. The principal aim of treatment is not reversal of existing fibrosis but preservation of viable lung parenchyma and lung function with delay in the clinical progression of the disease. The INBUILD trial showed nintedanib significantly reduced the decline of forced vital capacity (FVC) in patients with PPF, thereby solidifying the concept that antifibrotic therapy reduces the rate of decline of progressive fibrotic disease. However, evidence remains considerably less certain for mortality reduction in non-IPF PPF than the evidence for slowing physiological progression. The mortality benefit with antifibrotic treatment is better associated with IPF. Early treatment remains a defining strategy in reducing morbidity and preserving pulmonary functions. However, by contrast, established survival benefit across all forms of PPF is not clearly seen. Delaying treatment until severe physiological lung impairment develops may result in irreversible parenchymal lung damage without a significant therapeutic advantage. Therefore, the aim of future studies should be to determine whether early therapeutic intervention results in reduced hospitalisation, reduced exacerbation of the disease process and consequent mortality. Attempts should also be made to identify which PPF subgroups derive the greatest benefit from antifibrotic treatment.

Keywords: Early Treatment; Progressive Pulmonary Fibrosis; Pulmonary Fibrosis; Interstitial Lung Disease; Antifibrotic Therapy; Pirfenidone; Nintedanib; Forced Vital Capacity

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