An objective of the present invention is to provide a high-dose preparation having improved properties of a pharmaceutical composition comprising a hardly soluble basic drug, in particular, a compound represented by the formula (I) or a salt thereof.The above-mentioned objective can be solved by preparing a pharmaceutical composition containing a compound represented by the formula (I) or a salt thereof, a surfactant and a basic substance.本發明之目的係提供具有含有難溶性鹼性藥劑(尤其是式(I)表示之化合物或其鹽)之醫藥組成物之經改善之特性的高用量製劑。上述課題可藉由作成含有式(I)表示之化合物或其鹽、界面活性劑及鹼性物質之醫藥組成物來解決。
