Vortioxetine-d6 (Lu AA 21004-d6) is the deuterium labeled Vortioxetine. Vortioxetine (Lu AA 21004) is an antagonist of 5-HT 3A and 5-HT 7 receptors ( K i : 3.7 nM, 19 nM) and an inhibitor of serotonin transporter ( SERT ) ( K i : 1.6 nM), as well as a 5-HT 1A agonist and a partial agonist of 5-HT 1B ( K i : 15 nM, 33 nM).