ALK5-IN-8 is a highly effective inhibitor of TGFβRI (ALK5). It hinders the phosphorylation of ALK5 on downstream signaling proteins (Smad2 or Smad3) by obstructing the interaction between TGFβRI and ligands. Consequently, it disrupts or prevents TGF-β signaling. ALK5-IN-8 shows promise in the study of diverse diseases associated with ALK5-mediated pathways (taken from patent WO2021190425A1, compound 1) [1].