Selective leukocyte elastase inhibitor (IC50 = 44 nM) that displays no activity at a range of other proteases. Inhibits NF-κB activation and LTB4-induced neutrophil transmigration in vitro. Significantly attenuates ischemia-induced spinal cord injury, decreases serum cytokine levels and reduces acute inflammatory lung injury in vivo. Purity 98%. MW (observed): 456.44