The present invention provides a pharmaceutical composition or crystalline composition with a specific dissolution profile, which comprises suberoylanilide hydroxamic acid or a pharmaceutically acceptable salt or hydrate thereof as an active ingredient. The present invention provides a process of producing said crystalline composition or pharmaceutical composition. The present invention also provides compositions with a specific particle size distribution.本發明提供一種具有一特定溶解概況之醫藥組合物或結晶組合物,其包含1,8-辛二醯基苯胺羥胺酸(suberoylanilide hydroxamic acid)或其醫藥學上可接受之鹽或水合物作為活性成份。本發明提供一種製備該結晶組合物或醫藥組合物之方法。本發明亦提供具有一特定粒徑分佈之組合物。