Up-regulation of VEGF-A165b within the IPF lung and in patients who progressed after 1 year follow-up (Forced Vital Capacity (FVC) fall of ≥10% or death), suggests that the VEGF-Axxxb may be released as a compensatory protective mechanism against fibrogenesis, overwhelmed by other processes occurring within the lung. This evidence concerns the gene VEGFA and idiopathic pulmonary fibrosis.