The progressive fibrotic phenotype in current clinical practice

Abstract

Purpose of review: The progressive fibrotic phenotype (PFP), a term that covers large sub-groups of patients with fibrotic lung diseases that clinically progress despite appropriate usual management, is now an everyday problem for patients and clinicians alike. This review covers recent data that are relevant to major clinical uncertainties.

Recent findings: The clinical relevance of the PFP is covered by a brief review of data from which this entity was constructed. Estimates of the prevalence of the PFP are cited. The importance of an accurate initial diagnosis is emphasized - with refutation of the belief that diagnosis now matters less because of recent antifibrotic trial data. Pivotal trials are reviewed briefly with emphasis on the range of diseases studied and the efficacy signals. Included in this section are analyses of treatment effects in individual diseases and data that validate the progression criteria that define the PFP.

Summary: Clinicians can now implement the findings from recent antifibrotic trials in non-idiopathic pulmonary fibrosis lung diseases. However, the appropriate application of recent data requires an understanding of the critical importance of initial diagnosis, key measures of disease progression and knowledge of the strengths and weaknesses of trial data. Important clinical uncertainties not informed by current data include the evaluation of the adequacy of traditional management (before antifibrotic therapy is introduced) and agreement on the exact definition of disease progression that should trigger consideration of antifibrotic therapy.