PROBLEM TO BE SOLVED: To provide a novel polysaccharide derivative of EPO (erythropoietin) useful for improvement in stability, pharmacokinetics, and pharmacodynamics of EPO.SOLUTION: In a novel compound which is a polysaccharide derivative of EPO or an EPO like protein, the polysaccharide is anionic and comprises 2-200 saccharide units. A pharmaceutical composition comprising the novel compound, and a method for producing the novel compound are also provided.【課題】EPO(エリスロポエチン)の安定性、薬物動態、及び薬力学の改善に有用である、新規なEPOの多糖誘導体を提供する。【解決手段】EPO又はEPO様タンパク質の多糖誘導体である化合物であって、多糖がアニオン性であり、且つ2個~200個の糖ユニットを含む、化合物。新規化合物を含む医薬組成物、及び新規化合物の製造方法。【選択図】なし