The present Invention relates to pharmaceutical compositions of (3S,11aR)-N-[(2,4-difluorophenyl)methyl]-2,3,5,7,11,11a-hexahydro-6-hydroxy-3-methyl-5,7-dioxo-oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide, useful in the treatment or prevention of Human Immunodeficiency Virus (HIV) infections.本發明係關於用於治療或預防人類免疫缺陷病毒(HIV)感染的(3S,11aR)-N-[(2,4-二氟苯基)甲基]-2,3,5,7,11,11a-六氫-6-羥基-3-甲基-5,7-二側氧基-噁唑并[3,2-a]吡啶并[1,2-d]吡嗪-8-甲醯胺之醫藥組合物。(無元件符號說明)