Resolvin E1-d4 (RvE1-d4) is deuterium labeled Resolvin E1. Resolvin E1 (RvE1), a potent endogenous pro-resolving mediator of inflammation, is derived from omega-3 fatty acid eicosapentaenoic acid (EPA) . Resolvin E1 is endogenously biosynthesized from EPA in the presence of Aspirin during the spontaneous resolution phase of acute inflammation, where specific cell-cell interactions occur. Resolvin E1 possesses unique counterregulatory actions that inhibit polymorphonuclear leukocyte (PMN) transendothelial migration. Resolvin E1 also acts as a potent inhibitor of leukocyte infiltration, dendritic cell migration, and IL-12 production[1][2].