EGFR-IN-2 is a non-covalent, mutation-selective and irreversible second-generation EGFR inhibitor.

EGFR-IN-2 demonstrats strong antiproliferative effect on the T790M mutant carrying H1975 cell line (IC50=0.361 μM) and the single activating mutant PC9 cell line (IC50=0.151 μM). Furthermore, EGFR-IN-2 also shows good selectivity against other kinases when evaluated in a 225-kinase panel (12/225 kinases inhibited at >70% when tested at 0.1 μM, 61-fold over the TMLR Ki and 63-fold over the TMdel Ki).In addition, EGFR-IN-2 inhibits EGFR autophosphorylation with IC50s of 0.027 μM, 0.009 μM ,0.033 μM , and 0.218 μM in double mutant TMLR cell line H1975, double mutant TMdel cell line PC9-ER, activating mutant del

To examine its inhibitory effect on pEGFR levels in vivo, EGFR-IN-2 is studied in a mouse H1975 (TMLR) xenograft model. After a single oral dose of 21 at 50 mg/kg, free plasma concentrations of EGFR-IN-2 at or exceeding the in vitro p-EGFR IC50 of 0.027 μM are sustained over 8 h. When administered at 100 mg/kg, the coverage of p-EGFR IC50 is extended to the last measured time point of 16 h postdose. Corresponding knockdown of p-EGFR and the downstream effectors pERK1/2 and AKT levels are observed at those time points, suggesting target engagement in vivo.