Epertinib is a reversible and selective tyrosine kinase inhibitor of EGFR, HER2, and HER4 (IC50s: 1.48 nM, 7.15 nM, and 2.49 nM). It displays a strong antitumor activity.

HER4:7.15 nM, HER2:2.49 nM, EGFR:1.48 nM

Epertinib displays inhibitory activity against the growth of cancer cell lines expressing EGFR and/or HER2 (IC50s: 8.3 nM (NCI-N87 (stomach)), 9.9 nM (BT-474 (breast)), and 14 nM (SK-BR-3 (breast))) [1]. Epertinib shows no effect on KDR, IGF1R, SRC, KIT, and PDGFRβ (IC50, >10000 nM). Epertinib inhibits relative phosphorylation of EGFR and HER2 in NCI-N87 cells (IC50s: 4.5 and 1.6 nM) and it also inhibits MDA-MB-361 cell growth (IC50: 26.5 nM) [2].

Epertinib displays antitumor activity in nude mice bearing NCI-N87 xenograft via oral administration for 21 days ( ED50:10.2 mg/kg). Epertinib (50 mg/kg, p.o.) is four times more potent activity than GW572016 and completely inhibits the growth of cancer cells in mice [1] and it also obviously decreases the brain tumor volume in the breast cancer intraventricular injection mouse brain metastasis model [2].