In phase 2 studies, lebrikizumab reduced the number of exacerbations and improved lung function in patients with moderate‐to‐severe uncontrolled asthma, particularly in those with higher levels of T2 biomarkers such as periostin, blood eosinophils and fractional exhaled nitric oxide (FeNO).16, 20, 21. This evidence concerns the gene POSTN and asthma.