Lazertinib (YH25448,GNS-1480) is a potent, highly mutant-selective and irreversible EGFR-TKI with IC50 values of 1.7 nM, 2 nM, 5 nM, 20.6 nM and 76 nM for Del19/T790M, L858R/T790M, Del19, L85R and Wild type EGFR respectively, showing much higher IC50 values aganist ErbB2 and ErbB4.