Antitumor activity of TAS‐106 and dFdCyd in nude mouse models with(a) MIAPaCa‐2 and (b) MIAPaCa‐2/dFdCyd tumors. Control (○), TAS‐106 (▪, 7 mg/kg once weekly, i.v.), and dFdCyd (•, 240 mg/kg twice weekly, i.v.) were administered for 2 weeks. Points are mean ± standard deviation for six mice.