Product Overview
Cobimetinib is a selective inhibitor of mitogen-activated protein kinase kinase (MEK) with IC50 value of 0.9 nM. MEK is a kinase enzyme which selectively phosphorylates Ser/Thr and Tyr residues and involved in the mitogen-activated protein kinase (MAPK) signaling pathways that play an important role in regulation of cell proliferation, survival, differentiation, motility and angiogenesis. In a KRAS G13D and B-RAF G464V mutant MDA-MB-231T breast adenocarcinoma cells, Cobimetinib inhibited MEK with IC50 value of 0.2 nM. In pharmacokinetic-pharmacodynamic (PK-PD) model, Cobimetinib showed a sustained tumor pharmacodynamic response due to longer residence in tumor than in plasma. In WM-266-4 xenograft mice, Cobimetinib decreased %pERK in tumor with IC50 values of 0.78 (WM-266-4) and 0.52 mM. Also, Cobimetinib (3.89 mM) increased IC50 value in WM-266-4 mice. In A375 xenograft mice, Cobimetinib (0.3-30 mg/kg) showed antitumor efficacy in a dose-dependent way. Cobimetinib is currently in phase I clinical trials as a potential antitumor agent.