These targeted profibrotic cytokines from immune cells include TNFα, IL‐4, IL‐13, IL‐6, IL‐1, TGFβ, FGF, IFN‐γ, and IL‐1α.[45, 229] Although most of these drugs have entered clinical phases II and III, only Pirfenidone improved lung function and slowed down the progression of pulmonary fibrosis in IPF patients. This evidence concerns the gene TGFB1 and idiopathic pulmonary fibrosis.