Abstract: The present invention relates to a pharmaceutical composition for the treatment of type 2 diabetes, wherein the pharmaceutical composition contains (R)-7-[3-amino-4-(2,4,5-trifluo-phenyl)-butyryl]-3-trifluomethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid methyl ester or its pharmaceutically acceptable salts and metformin or its pharmaceutically acceptable salts (such as hydrochlorate), preparation method thereof and method of treating 2 type diabetes with the composition.本發明公開了治療2型糖尿病的藥物組合物,特別是含有(R)-7-[3-胺基-4-(2,4,5-三氟-苯基)-丁醯基]-3-三氟甲基-5,6,7,8-四氫-咪唑並[1,5-a]吡嗪-1-羧酸甲酯或者其鹽和二甲雙胍或者其鹽(如鹽酸鹽)的固定劑量組合的藥物組合物,製備該藥物組合物的方法和使用該藥物組合物治療2型糖尿病的方法。本案無圖式