IL1A and pulmonary fibrosis: 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.