Varespladib is an inhibitor of the IIa, V, and X isoforms of secretory phospholipase A2 (sPLA2). The molecule acts as an anti-inflammatory agent by disrupting the first step of the arachidonic acid pathway of inflammation. From 2006 to 2012, varespladib was under active investigation by Anthera Pharmaceuticals as a potential therapy for several inflammatory diseases, including acute coronary syndrome and acute chest syndrome. The trial was halted in March 2012 due to inadequate efficacy. The selective sPLA2 inhibitor varespladib (IC50 value 0.009 µM in chromogenic assay, mole fraction 7.3X10-6) was studied in the VISTA-16 randomized clinical trial (clinicaltrials.gov Identifier: NCT01130246) and the results were published in 2014. The sPLA2 inhibition by varespladib in this setting seemed to be potentially harmful, and thus not  a useful strategy for reducing adverse cardiovascular outcomes from acute coronary syndrome. Since 2016, scientific research has focused on the use of Varespladib as an inhibitor of snake venom toxins using various types of  in vitro and in vivo models. Varespladib showed a significant inhibitory effect to snake venom PLA₂ which makes it a potential first-line drug candidate in snakebite envenomation therapy.  In 2019, the U.S. Food and Drug Administration (FDA) granted varespladib orphan drug status for its potential to treat snakebite.