MAP855 is a highly potent, selective, ATP-competitive and orally active MEK1/2 kinase inhibitor (MEK1 ERK2 cascade IC50=3 nM, pERK EC50=5 nM). MAP855 shows equipotent inhibition of wild-type and mutant MEK1/2[1].

MAP855 (compound 30) has single-digit nM inhibition of pERK and proliferation in A375 cells (pERK EC50=5 nM)[1].

MAP855 (3 mg/kg for i.v., 10 mg/kg for p.o.; single) has good oral bioavailability and medium clearance in rodents[1].MAP855 (30 mg/kg; p.o., b.i.d, 14 days) achieves comparable efficacy to trametinib dosed at the mouse MTD without any body weight loss[1].Pharmacokinetic Parameters of MAP855 in mouse, rat and dog[1]. mouse rat dog CL [mL/min*kg]323522V_{ss [l/kg]2.62.01.8AUC po d.n. [μM*h]0.40.61.4 Oral BAV [% F]4465100}

[1]. Poddutoori R, et al. Discovery of MAP855, an Efficacious and Selective MEK1/2 Inhibitor with an ATP-Competitive Mode of Action. J Med Chem. 2022;65(5):4350-4366.