The purpose of the present invention is to provide a medicine or a cancer therapy method each using a combination of a compound having an MDM2 inhibitory activity and a DNA methyltransferase inhibitor. Provided is a medicine or a combination therapy method each using a combination of (3'R,4'S,5'R)-N-[(3R,6S)-6-carbamoyltetrahydro-2H-pyran-3-yl]-6"-chloro-4'-(2-chloro-3-fluoropyridin-4-yl)-4,4-dimethyl-2"-oxo-1",2"-dihydrodispiro[cyclohexane-1,2'-pyrrolidine-3',3"-indole]-5'-carboxamide or a pharmaceutically acceptable salt thereof and a DNA methyltransferase inhibitor.