Potent irreversible pan ErbB inhibitor (IC50 values are 6.0, 45.7 and 73.7 nM for EGFR, ERBB2 and ERBB4, respectively). Inhibits mutant and wild type forms of ErbB, including EGFR T780M, and shows activity in NSCLC cell lines sensitive and resistant to Iressa (Cat.No. 3000). Inhibits tumor growth. Orally bioavailable. Purity 98%. MW (observed): 469.94