PROBLEM TO BE SOLVED: To provide highly concentrated protein drug formulations useful and beneficial for subcutaneous administration or delivery.SOLUTION: A concentrated protein formulation contains an antibody or a fragment of the antibody, a monoclonal antibody or a fragment of the monoclonal antibody, a polyclonal antibody or a fragment of the polyclonal antibody, a humanized antibody containing PRO140 or a fragment of PRO140, or a fragment of the humanized antibody, a human antibody or a fragment of the human antibody, or a hybrid antibody or a fragment of the hybrid antibody; and an isotonic agent of a salt and buffer present in a total amount of 110-120 mM, in which the salt is present in an amount of less than 100 mM, the concentrated protein is present in an amount of more than 162 mg/mL and less than 200 Mg/mL, the formulation being hypotonic.SELECTED DRAWING: None【課題】皮下投与または送達するのに有用かつ有益である高濃度のタンパク質薬物製剤の提供。【解決手段】抗体もしくは該抗体の断片、モノクローナル抗体もしくは該モノクローナル抗体の断片、ポリクローナル抗体もしくは該ポリクローナル抗体の断片、PRO140もしくはPRO140の断片を含むヒト化抗体もしくは該ヒト化抗体の断片、ヒト抗体もしくは該ヒト抗体の断片、または、ハイブリッド抗体もしくは該ハイブリッド抗体の断片;110mM~120mMの合計量で存在する塩と緩衝剤の等張剤を含む濃縮されたタンパク質製剤であって、ここで、該塩が、100mM未満の量で存在し、該濃縮されたタンパク質が、162mg/mLを超え、200mg/mL未満の量で存在し、該製剤は低張である、前記製剤。【選択図】なし