The invention relates to pharmaceutical compositions comprising N-(3,5-dimethoxyphenyl)-N′-(1-methylethyl)-N-[3-(1-methyl-1H-pyrazol-4-yl)quinoxalin-6-yl]ethane-1,2-diamine, or a pharmaceutically acceptable salt thereof or a solvate thereof; to processes for the preparation of said compositions and to the use of said compositions for the manufacture of a medicament for the prophylaxis of or the treatment, in particular the treatment, of diseases, e.g. cancer