PROBLEM TO BE SOLVED: To provide liquid formulations of antibodies and biologically active fragments thereof that specifically bind to a human ICOS polypeptide, exhibit increased in vivo ADCC activity, exhibit chemical and physical stability during preservation, have a long shelf life, and undergo reversible self-association.SOLUTION: The invention provides an aqueous formulation comprising an antibody that specifically binds to a human ICOS, wherein a) the antibody comprises an Fc region having complex N-glycoside-linked sugar chains in which fucose is not bound to N-acetylglucosamine in the reducing end in the sugar chain； b) the antibody undergoes reversible self-association in solution, wherein the reversible self-association does not induce aggregate formation； and c) at least 10 mole percent of the antibody exists as a trimer in PBS at 10 mg/mL antibody concentration at 37°C.【課題】ヒトＩＣＯＳポリペプチドに特異的に結合し、増加したインビボＡＤＣＣ活性を示し、保存中の化学的及び物理的な安定性を示し、有効期の長い、溶液中で可逆的な自己会合を起こす抗体及びその生物活性断片の液体製剤の提供。【解決手段】ａ）フコースが糖鎖の還元末端のＮ－アセチルグルコサミンと結合しない複合Ｎ－グリコシド結合糖鎖を有するＦｃ領域を含み、ｂ）溶液中で可逆的な自己会合を起こし、前記可逆的な自己会合は、凝集体形成を誘発せず、且つ、ｃ）前記抗体の少なくとも１０モル％は、３７℃、１０ｍｇ／ｍＬの抗体濃度のＰＢＳ中で三量体として存在する、ヒトＩＣＯＳに特異的に結合する抗体を含む水性製剤。【選択図】図１
