Sivelestat (ONO-5046) is a potent neutrophil elastase inhibitor. It acts as a substrate-competitive, and highly specific inhibitor of neutrophil elastase (IC₅₀ = 19-49 nM in rat, rabbit, hamster, human, and mouse leukocyte elastase). Sivelestat displays >100-fold greater selectivity over pancreatic elastase (IC₅₀ = 5.6 µM). It does not inhibit trypsin, thrombin, plasmin, kallikrein, chymotrypsin, and cathepsin G even at concentrations as high as 100 µM.
≥97% by HPLC