In H1975 mouse xenograft model, Nazartinib (EGF816; 50 and 20 mg/kg or 25 mg/kg, p.o.) demonstrates dose-dependent efficacy with near complete tumor cells regression at the highest dose tested (50 mg/kg)[1]. In H1975 mouse model, Nazartinib (EGF816; 10 mg/kg, p.o.) induces tumor growth inhibition with a T/C (tumor/control volume) of 29%, and when doses are 30 and 100 mg/kg, tumor regressions are achieved (T/C, 61% and 80%, respectively). In the H3255 xenograft model, Nazartinib (30 mg/kg, p.o.) shows significant antitumor activity. Antiproliferative activity of Nazartinib on 89 lung cancer cell lines indicates that Nazartinib selectively inhibits cell lines containing EGFR with catalytic domain mutations[2].