Inhibits the enzymatic activity of basic and acidic PLA2 from B.jararacussu and B.pauloensis, respectively, in a dose-dependent manner. Also inhibits myotoxicity and cytotoxicity of BnSp-7 of B.pauloensis. Forms dimers or higher order oligomers in a temperature-dependent manner in vitro. Secreted in blood plasma. Expressed by the liver. Belongs to the CNF-like-inhibitor family.