Amustaline (S-303) is a quinacrine mustard compound with potential antineoplastic activity. Amustaline binds to, intercalates and crosslinks DNA and RNA. This agent is mainly used for ex vivo purposes, specifically for the inactivation of pathogens such as viruses, protozoa and bacteria in red blood cells (RBCs). When S-303 is added to red blood cells, the compound rapidly passes through membranes, including those of cells and viral envelopes, due to its amphipathic character, and intercalates into helical regions of the nucleic acids of pathogens and white blood cells. TERCEPTTMBlood System usingamustaline (S-303) and glutathione (GSH) was able to inactivate high levels of DENV and ZIKV in RBCs. S-303 system has been shown to effectively inactivate a broad spectrum of pathogens, while maintaining RBC quality.