Biological Activity
Pelitinib (EKB-569;WAY-EKB 569) is an irreversible inhibitor of EGFR with an IC50 of 38.5 nM; also slightly inhibits Src, MEK/ERK and ErbB2 with IC50s of 282, 800, and 1255 nM, respectively.
In Vitro
Pelitini has much greater inhibitory activity against the EGFR kinase than against Src, MEK/ERK, Cdk4, c-Met, Raf and ErbB2, for example, the IC50 for EGFR is 32-fold lower than the IC50 for the closely related ErbB2. Pelitinib results in a dramatic reduction in EGFR phosphorylation but no change in the total amount of EGFR protein. It requires at least 10-fold more drug to equivalently inhibit ErbB2 phosphorylation in similar assays, and EKB-569 does not block phosphorylation of another receptor tyrosine kinase (c-Met) assessed in the same manner[1]. EKB-569 is a potent inhibitor of proliferation in NHEK, A431, and MDA-468 cells (IC50=61, 125, and 260 nM, respectively) but not MCF-7 cells (IC50=3600 nM). EKB-569 is also a potent inhibitor of EGF-induced phosphorylated EGF-R (pEGF-R) in A431 and NHEK cells (IC50=20-80 nM)[1].
In Vivo
A single oral dose of 10 mg/kg EKB-569 inhibits EGFR phosphorylation in A431 xenografts within 60 minutes. Twenty-four hours later, EGFR activity is still inhibited by over 50% by this single oral dose. The half-life of EKB-569 in mouse plasma is about 2 hours[1].
References & source
Published experimental findings depend on the model and assay conditions. They do not guarantee equivalent performance in every application. For laboratory research use only.
