1,2,3-Trieicosapentaenoyl-rac-glycerol (EPA-TG) is a glycerol ester of eicosapentaenoic acid , which is an ω-3 fatty acid. An EPA-TG emulsion, administered i.v., lowers leukotriene B4 production by 40% in polymorphonuclear leukocytes from rabbits and reduces platelet aggregation. It suppresses natural killer cell activity both in vitro and in vivo, in human lymphocytes and murine spleens, respectively, with the in vivo effects lasting up to seven days.