SKOV3 xenografts, over-expressing HER2, EGFR, HER3, and HER4 exhibited an average tumor growth delay that ranged from 17.1 days (15 mg/kg) to 41.2 days (30 mg/kg) after treatment with dacomitinib and complete tumor regressions at doses as low as 15 mg/kg. The gene discussed is ERBB2; the disease is neoplasm.