This randomised, double-blind, placebo-controlled study is one of the largest multicentre studies investigating whether ambrisentan (an endothelin A receptor antagonist) reduces the rate of idiopathic pulmonary fibrosis (IPF) progression.

The investigators compared ambrisentan (more commonly used in the treatment of pulmonary hypertension (PH)) with placebo on the basis of preclinical studies suggesting endothelin …