The present invention relates to a method for screening for an antibody comprising a domain containing an antibody variable region that binds to glypican 3 and a domain containing an antibody variable region that binds to a T cell receptor complex and a common light chain capable of improving affinity for both antigens An anti-cancer agent containing the bispecific antibody as an active ingredient, and a pharmaceutical composition for use in combination with another anti-cancer agent containing the bispecific antibody as an active ingredient. The bispecific antibody is a novel molecule having high production efficiency and strong antitumor activity and safety and excellent pharmacokinetics and is expected to be applied to various cancers.本発明は、グリピカン3に結合する抗体可変領域を含むドメインと、T細胞受容体複合体に結合する抗体可変領域を含むドメインに、両抗原に対する親和性を向上させることが可能な共通L鎖を含む二重特異性抗体を有効成分とする抗癌剤、および、当該二重特異性抗体を有効成分とする他の抗癌剤と併用するための医薬組成物を提供する。当該二重特異性抗体は高い産生効率を有し、かつ強い抗腫瘍活性および安全性と優れた薬物動態を持つ新たな分子であり、様々な癌への適用が期待される。
