Cyclo(RGDyK) is a potent and selective inhibitor of αVβ3 integrin . It significantly reduces lung inflammation and fibrosis induced by influenza A virus, and improves lung morphology, lowers pulmonary fibrosis scores, and suppresses the expression of αVβ3, TGF-β1, NF-κB p65, p38 MAPK, and HIF-1α, confirming its protective effects against ALI and pulmonary fibrosis.