Mice were administered the IDO1 inhibitors, i.e., YH29407 (100 mg/kg, Q.D. or B.I.D.), epacadostat (100 mg/kg, B.I.D.), and BMS-986205 (100 mg/kg, Q.D.)when the mean tumor size reached 50 mm3 (Figure 1A). The gene discussed is IDO1; the disease is neoplasm.