| abstract |
The present invention relates to a conjugate in which an FL118 drug is linked to an acid-sensitive linker, and an immunoconjugate using same. In the present invention, one or more FL118 drugs of chemical formula 1 are linked to an antibody or an antigen-binding site-containing fragment thereof through an acid-sensitive linker, and after being targeted to cancer cells by an antigen-binding site that targets an antigen of the cancer cells, the acid-sensitive linker is decomposed in an acidic environment around cancer (pH ≤ 7) so that at least a part of the FL118 drug of chemical formula 1 is liberated, the free FL118 drug of chemical formula 1 penetrates the cell membrane and migrates into cells, and the FL118 drug of chemical formula 1 inhibits the action of an efflux pump, and thus the free FL118 drug of chemical formula 1 is concentrated in the cells. |