PROBLEM TO BE SOLVED: To provide an antibody or an antigen-binding fragment which specifically binds to the proprotein converting enzyme subtilisin / kexin 9 (PCSK9), a pharmaceutical composition containing the antibody or the antigen-binding fragment, and a method of use. SOLUTION: In one embodiment, PCSK9 and low-density lipoprotein are bound to PCSK9, which comprises a heavy chain CDR and a light chain CDR selected from the heavy chain and light chain sequences of a hybridoma obtained by using a PCSK9 recombinant protein as an antigen. Antibodies or antigen-binding fragments that inhibit binding to protein receptors and increase uptake of low-density lipoprotein cholesterol, pharmaceutical compositions containing the antibodies or antigen-binding fragments, and cardiovascular diseases associated with dyslipidemia. Use in the manufacture of therapeutic agents. [Selection diagram] None【課題】プロタンパク質転換酵素サブチリシン／ケキシン９（ＰＣＳＫ９）に特異的に結合する抗体または抗原結合断片体、該抗体または該抗原結合断片を含む医薬組成物、および使用方法の提供。【解決手段】一態様において、ＰＣＳＫ９組換えタンパク質を抗原として得られたハイブリドーマの重鎖および軽鎖の配列から選択される重鎖ＣＤＲと軽鎖ＣＤＲを含む、ＰＣＳＫ９に結合しＰＣＳＫ９と低密度リポタンパク質受容体との結合を阻害して低密度リポタンパク質コレステロールの取り込みを増加させる抗体または抗原結合断片、該抗体または該抗原結合断片を含む医薬組成物、および脂質異常症と関連する心臓血管疾患を治療する医薬の製造における使用。【選択図】なし
