PROBLEM TO BE SOLVED: To provide novel humanized monoclonal antibodies and bispecific antibodies that specifically bind to IL-4 and/or IL-13, fragments and derivatives thereof, as well as pharmaceutical compositions for treating diseases and disorders associated with functions and metabolism of IL-4 and/or IL-13.SOLUTION: Humanized anti-IL-4 and IL-13 antibodies and fragments thereof are prepared by using genetic engineering technique, and an antibody fragment having two antigen-binding sites is further prepared.【課題】ＩＬ－４及び／又はＩＬ－１３に特異的に結合する、新規ヒト化モノクローナル抗体及び二重特異性抗体、並びにそれらのフラグメント及び誘導体の提供。ＩＬ－４及び／又はＩＬ－１３機能及び代謝に関連する疾患及び障害を治療する医薬組成物の提供。【解決手段】遺伝子改変技術により、ヒト化抗－ＩＬ－４及びＩＬ－１３抗体及びそれらのフラグメントを作製し、さらに２つの抗原結合性部位を有する抗体フラグメントを作製する。【選択図】図１
