BI 1015550: an investigational phosphodiesterase 4B (PDE4B) inhibitor for lung function decline in idiopathic pulmonary fibrosis (IPF).

Oral treatment with BI 1015550 was shown to stabilize lung function as compared to placebo over 12 weeks, both among patients with and without background antifibrotic use, with an acceptable safety profile in a phase 2 trial, and a phase 3 trial has been initiated. To date, this represents to date the largest effect size for an IPF investigational drug tested in a phase 2 trial with the shortest duration.