Definition

A radiolabeled antibody-targeted antineoplastic antibiotic consisting of the enediyne antibiotic calicheamicin conjugated with anti-Lewis Y antibody and labeled with indium In 111. In 111 CMD-193 binds to Lewis Y antigen-expressing tumor cells via its antibody moiety and is internalized; subsequently, the calicheamicin moiety binds to the minor groove of tumor cell DNA, causing double-strand DNA breaks, the inhibition of DNA synthesis, and apoptosis. The indium In 111 radiolabel allows the detection of CMD-193 distribution and tumor localization using gamma scintigraphy.