NCIt definition : An immunoconjugate consisting of a humanized monoclonal antibody that is engineered
to contain cysteine residues that are conjugated to the synthetic, DNA cross-linking,
pyrrolobenzodiazepine dimer SGD-1882, via the protease-cleavable linker maleimidocaproyl-valine-alanine
dipeptide, with potential antineoplastic activity. The monoclonal antibody portion
of vadastuximab talirine specifically binds to the cell surface antigen CD33. This
causes the internalization of SGN-CD33A, and the release of the cytotoxic moiety SGD-1882.
SGD-1882 binds to and crosslinks DNA, which results in both cell cycle arrest and
the induction of apoptosis in CD33-expressing tumor cells. CD33, a transmembrane receptor,
is expressed on myeloid leukemia cells.;