Definition

An antibody-drug conjugate (ADC), consisting of a human monoclonal antibody directed against AXL receptor tyrosine kinase (AXL; UFO) and conjugated, through a protease-cleavable linker, to the cytotoxic agent monomethyl auristatin E (MMAE), with potential antineoplastic activity. Upon administration, the monoclonal antibody moiety of HuMax-AXL-ADC binds to AXL, which is expressed on the surfaces of a variety of cancer cell types. Upon endocytosis and enzymatic cleavage, MMAE is released into the tumor cell cytosol, where it binds to tubulin and inhibits tubulin polymerization; this may result in G2/M phase arrest and apoptosis. AXL, a member of the TAM (TYRO3, AXL and MER) family of receptor tyrosine kinases and overexpressed by many tumor cell types, plays a key role in tumor cell proliferation, survival, invasion and metastasis; its expression is associated with drug resistance and poor prognosis.