PROBLEM TO BE SOLVED: To provide a two-step method for the purification of a divalent cation-binding protein with high yield and high purity on an anion exchange resin material, a divalent cation binding protein obtainable by the method, and a kit comprising means for carrying out the method.SOLUTION: According to the invention, there is provided a recombinant FIX having a specific activity of at least 270 I.U./mg FIX Ag, a pharmaceutical composition comprising the recombinant FIX in which CHO DNA is included in amount of less than 10 pg/ml, or a recombinant FIX composition including less than 1 mU FIXa (activated FIX) activity/unit FIX clotting activity.SELECTED DRAWING: None【課題】二価カチオン結合タンパク質をアニオン交換樹脂材料にて高収率および高純度で精製する二段階方法、該方法により得られる二価カチオン結合タンパク質、および該方法を実施するための手段を含むキットに関する。【解決手段】少なくとも２７０Ｉ.Ｕ.／ｍｇ ＦＩＸ Ａｇの比活性を有する、組換えＦＩＸ、１０ｐｇ／ｍｌ未満のＣＨＯ ＤＮＡを含む、組換えＦＩＸを含む医薬組成物、又は１ｍＵ未満のＦＩＸａ（活性化ＦＩＸ）活性／単位のＦＩＸ凝固活性を含む、組換えＦＩＸ組成物。【選択図】なし
