EMD534085

EMD534085 is a potent and selective inhibitor of the mitotic kinesin-5 with an IC₅₀ of 8 nM. IC50 & Target: IC50: 8 nM (kinesin-5)^[1] In Vitro: EMD 534085 does not inhibit any other tested kinesins (BimC, CEN-PE, Chromokinesin, KHC, KIF3C, KIFC3, MKLP-1, and MCAK) at 1 μM or 10 μM concentration, showing selectively over kinesin-5. EMD 534085 binds to the allosteric pocket of kinesin-5^[1]. EMD534085 induces rapid cell death in HL60 during mitotic arrest. Caspase-8, −9, −3, −7 are activated; Parp1 is cleaved; Mcl1 and XIAP are degraded in EMD534085-treated HL60 cells. EMD534085 treated HL60 cells also shows significantly accumulated phospho-Histone H3 level starting at 6 hrs post thymidine release^[2]. In Vivo: In a low dose PK of EMD 534085 in mice the clearance is 1.8 L/h/kg on average, the volume of distribution is 7.4 L/kg and the half life around 2.5 h. The bioavailability in high dose experiments (>10 mg/kg) is always above 50% in mice. Intraperitonal administration of EMD 534085 enables significant systemic exposure in mice leading to a significant tumor growth reduction without toxic side effects^[1].