The present application provides a pharmaceutical composition for use in treatment or remission of patients with chronic myelogenous leukemia, wherein the composition comprises, as active ingredients, (2S)-2-[(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoylamino]-4-methylpentanoic acid or a pharmacologically acceptable salt thereof, and 4-[(4-methyl-1-piperazinyl)methyl]-N-[4-methyl-3-[[4-(3-pyridinyl)-2-pyrimidinyl]amino]phenyl]-benzamide or a pharmacologically acceptable salt thereof, both of which are used at low doses.