AST-1306 is a selective, irreversible inhibitor of ErbB2 and EGFR with IC50 values of 0.5nM and 3nM, respectively [1].

AST-1306 is designed and synthesized based on the chemical structure of lapatinib. The molecular docking method shows AST-1306 binds to the ATP-binding pocket of the kinases and form covalent bind with certain amino acids. AST-1306 can inhibit EGFR and ErbB2 in a cell-free assay with more than 3000-fold selectivity to other kinases. Besides the wild-type EGFR, AST-1306 also inhibits EGFR mutant T790M/L858R both in a cell-free assay and in HIH3T3 cells. The growth of the cells is suppressed by AST-1306 due to the inhibition of the phosphorylation of EGFR. It also occurs in some human cancer cells. Experiments have proved that AST-1306 notly inhibits the phosphorylation of EGFR and ErbB2 and subsequently decreases the downstream pathways of these kinases in A549 cells, Calu-3 cells and SK-OV-3 cells. Moreover, AST-1306 potently inhibits the tumor growth both in ErbB2-overexpressing xenograft models and FVB-2/Nneu transgenic mouse model [1].

References:
[1] Xie H, Lin L, Tong L, Jiang Y, Zheng M, Chen Z, Jiang X, Zhang X, Ren X, Qu W, Yang Y, Wan H, Chen Y, Zuo J, Jiang H, Geng M, Ding J. AST1306, a novel irreversible inhibitor of the epidermal growth factor receptor 1 and 2, exhibits antitumor activity both in vitro and in vivo. PLoS One. 2011;6(7):e21487.