Varespladib is a selective inhibitor of human, group IIA, nonpancreatic secretory PLA2 (sPLA2). In a chromogenic isolated enzyme assay, Varespladib inhibited sPLA2 activity with an IC50 of 9 6 ±1 nM or 7.3 *10-6 mole fraction, which approached the stiochiometric limit of this assay.Varespladib was 40-fold less active against human, group IB, pancreatic sPLA2 and was inactive against cytosolic PLA2 and the constitutive and inducible forms of cyclooxygenase.Human sPLA2-induced release of thromboxane A2 (TXA2) from isolated guinea pig lung bronchoalveolar lavage cells was inhibited by Varespladib with an IC50 of 0.79 nM. Therefore£¬the use of Varespladib have a beneficial effect in preventing various inflammatory disease states.

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