PROBLEM TO BE SOLVED: To provide anti-survivin antibodies or antibody derivatives which have high reactivity.SOLUTION: The present invention provides an anti-survivin antibody or antibody derivative which comprises a specific amino acid sequence, or a variable region having a first region consisting of an amino acid sequence in which one or some amino acids are deleted, substituted, or added in a specific amino acid sequence, a second region in which one or some amino acids are deleted, substituted, or added in a specific amino acid sequence, and a third region in which one or some amino acids are deleted, substituted, or added in a specific amino acid sequence, the anti-survivin antibody or antibody derivative being an antibody fragment (VHH antibody) consisting of a variable domain of a heavy chain antibody.SELECTED DRAWING: NoneCOPYRIGHT: (C)2017,JPO&INPIT【課題】反応性の高い抗サバイビン抗体又は抗体誘導体の提供。【解決手段】特定のアミノ酸配列、又は特定のアミノ酸配列において1若しくは数個のアミノ酸が欠失、置換若しくは付加されたアミノ酸配列からなる第1領域と、特定のアミノ酸配列において1若しくは数個のアミノ酸が欠失、置換若しくは付加されたアミノ酸配列からなる第2領域と、特定のアミノ酸配列において1若しくは数個のアミノ酸が欠失、置換若しくは付加されたアミノ酸配列からなる第3領域と、を有する可変領域を備える、抗サバイビン抗体又は抗体誘導体。重鎖抗体の可変ドメインからなる抗体断片(VHH抗体)である抗サバイビン抗体又は抗体誘導体。【選択図】なし
