The present invention relates a pharmaceutical composition comprising JAK kinase inhibitor or its medicinal salt thereof. In particular, the present invention relates a pharmaceutical composition comprising (3aR,5s,6aS)-N-(3-methoxyl-1,2,4-thiadiazole-5-yl)-5-(methyl(7H-pyrrolo[2,3 -d]pyrimidine-4-yl)amino)hexahydrocyclopenta[c]pyrrole-2(1 H)-formamide or its medicinal salt and cellulose ether. The composition has the characteristics of rapid dissolution and good stability.本發明提供了一種含有JAK激酶抑制劑或其可藥用鹽的醫藥組成物。具體而言，本發明提供了一種醫藥組成物，含有(3aR,5s,6aS)-N-(3-甲氧基-1,2,4-噻二唑-5-基)-5-(甲基(7H-吡咯并[2,3-d]嘧啶-4-基)胺基)六氫環戊并[c]吡咯-2(1H)-甲醯胺或其可藥用鹽和纖維素醚。本發明的醫藥組成物具有溶出迅速、穩定性良好的特點。
