Nafamostat is a serine protease inhibitor that is capable of inhibiting trypsin (a digestive system protease; Ki = 15 nM), tryptase (a mast cell protease; Ki = 95.3 pM), and additional proteases in the coagulation cascade including thrombin (Ki = 0.84 μM). In a mouse model of allergic asthma, a dose of 300 mg/kg nafamostat mesylate has been shown to inhibit serine proteolytic activity, to decrease circulating levels of eosinophils and lymphocytes in bronchoalveolar lavage fluid, and to reduce interleukin-13 and eotaxin production associated with antigen-induced airway eosinophilia and goblet cell hyperplasia.
