A composition comprising a substance represented by general formula (I) a pharmaceutically acceptable carrier and a dissolution aid is useful for the improvement in the solubility oral absorbability and/or absorbability in blood of the poorly water soluble or water insoluble tetracyclic compound that is useful as a prophylactic and/or therapeutic agent for cancer depression and cognitive dysfunction and has an ALK inhibitory activity. In the formula the symbols are as defined in the description.
