Pirfenidone is a potent anti-fibrotic TGF-β inhibitor. It affects TGF-β/Smad, NF-κB, and Wnt/β-catenin signaling pathways by blocking Smad2/3 phosphorylation and modulating MAPK activation, effectively inhibiting fibroblast-to-myofibroblast differentiation and extracellular matrix production to attenuate fibrosis.