An anti-PD-L1 antibody capable of frequent administration to animals other than rats is provided. (a) A CDR1 having the amino acid sequence of QSLLYSENQKDY (SEQ ID NO: 37), a CDR2 having the amino acid sequence of WAT, and a light chain variable region comprising CDR3 having the amino acid sequence of GQYLVYPFT (SEQ ID NO: 38) The amino acid sequence of the L chain having the L chain constant region, the CDR1 having the amino acid sequence of (b) GYTFTSNF (SEQ ID NO: 39), the CDR2 having the amino acid sequence of IYPEYGNT (SEQ ID NO: 40) and ASEEAVISLVY (SEQ ID NO: 41) An anti-PD-L1 antibody comprising a heavy chain variable region comprising CDR3 and a heavy chain having a heavy chain constant region of a non-rat animal antibody. A pharmaceutical composition comprising the anti-PD-L1 antibody as an active ingredient. Also provided is a method of producing the anti-PD-L1 antibody.ラット以外の動物にも頻回投与が可能な抗PD-L1抗体を提供する。(a)QSLLYSENQKDY（配列番号３７）のアミノ酸配列を有するCDR1、WATのアミノ酸配列を有するCDR2及びGQYLVYPFT（配列番号３８）のアミノ酸配列を有するCDR3を含むL鎖可変領域と、ラット以外の動物抗体のL鎖定常領域とを有するL鎖と、(b)GYTFTSNF（配列番号３９）のアミノ酸配列を有するCDR1、IYPEYGNT（配列番号４０）のアミノ酸配列を有するCDR2及びASEEAVISLVY（配列番号４１）のアミノ酸配列を有するCDR3を含むH鎖可変領域とラット以外の動物抗体のH鎖定常領域とを有するH鎖とを含む、抗PD-L1抗体。前記抗PD-L1抗体を有効成分として含む、医薬組成物。前記抗PD-L1抗体を製造する方法も提供する。
