Potent dual specificity EGFR/HER2 inhibitor (IC50 are 0.4, 0.5, 10, 14, 1 nM for EGFRL858R, EGFRwt, EGFR L858R/T790M, ErbB2 (HER2) and ErbB4 (HER4), respectively). 100-fold more active than Gefitinib in L858R-T790M EGFR double mutant cell line. Irreversibly binds EGFR and HER2. Suppresses the kinase activity of wild-type and activated EGFR and HER2 mutants, including erlotinib-resistant isoforms. Induces tumor regression in xenograft and transgenic lung cancer models. Purity 98%. MW (observed): 718.08