PROBLEM TO BE SOLVED: To provide a new fibroblast growth factor (FGF) peptide conjugate by controlled modification of FGF with one or more modifying groups (e.g., non-glycosidic modifying group), which conjugate has an improved pharmacokinetic properties in comparison with the corresponding native (not modified) FGF, further to provide a reliable, reproducible and cost-effective method for producing FGF peptide conjugate.SOLUTION: The FGF conjugate comprises a mutated FGF peptide and at least one modifying group, where the peptide contains newly introduced N-linked or O-linked glycosylation site not present in the wild type FGF, and has an amino acid sequence of 95% homology to the wild type FGF, and/or the newly introduced N-linked or O-linked glycosylation site is proximate to a proline residue, the modifying group is covalently bonded to the peptide at a predetermined glycosyl or amino residue through an intact glycosyl linking group, that is, the saccharide monomer that links the modifying group to the remainder of the molecule is not degraded.【課題】一個以上の修飾基（例えば、非グルコシド修飾基）で線維芽細胞成長因子（ＦＧＦ）を制御修飾することで、対応天然（非修飾）ＦＧＦに比し改良された薬動力学物性を有する新規ＦＧＦペプチド複合体を得、更にＦＧＦペプチド複合体の信頼性と再現性のある費用効率の高い産生法を提供する。【解決手段】変異ＦＧＦペプチド及び修飾基からなり、対応する野生型ＦＧＦには存在しない新規導入のＮ連結又はＯ連結グリコシル化部位を含み、野生型ＦＧＦに少なくとも９５％相同なアミノ酸配列を有し、及び／又は、該新規導入のＮ連結又はＯ連結グリコシル化部位は、プロリン残基付近であり、該修飾基は、無傷グリコシル結合基、すなわち分子残部に該修飾基を連結する糖類単量体が分解しないグリコシル結合基、により該変異ＦＧＦペプチドの予め選択されたグリコシル又はアミノ残基位で該ペプチドと共有結合した、ＦＧＦ複合物。【選択図】なし
