ANTIBODY SPECIFICALLY BINDING TO HER2

摘要

The present invention relates to a novel HER2 antibody for concomitant administration which is used for preventing or treating cancer. The antibody of the present invention specifically binds to HER2, which is overexpressed in cancer cells (particularly, breast cancer and gastric cancer cells), and binds to an epitope different from that to which trastuzumab binds. The antibody of the present invention has a unique sequence due to a very low homology compared with the CDR sequence of known HER2-targeting antibodies. The antibody of the present invention kills cancer cells with remarkably improved cancer cell killing ability when concomitantly administered with trastuzumab, and is thus very useful for preventing or treating cancer (particularly, breast cancer and gastric cancer). The remarkable efficacy of concomitant administration of the antibody of the present invention is considered, without wishing to be bound by theory, to be due to the antibody of the present invention binding to an epitope of HER2 different from that to which trastuzumab binds, thereby inhibiting HER2 cooperatively with trastuzumab.