The present disclosure relates to a novel
antibody-
drug conjugate (ADC) targeting
claudin 18 isoform 2 (CLDN18.2), an
active metabolite of the ADC, a method of producing the ADC, use of the ADC for the treatment and / or prevention of diseases, and use of the ADC for producing a
drug for the treatment and / or prevention of diseases, more specifically hyperproliferative and / or angiogenic diseases, for example,
cancer, and more particularly, to an
antibody-
drug conjugate including a novel
antibody or
antigen-binding fragment thereof that binds to CLDN18.2, and a pharmaceutical composition including the same.