Definition

An antibody-drug conjugate (ADC) composed of OMTX005, a humanized monoclonal antibody directed against fibroblast activation protein (FAP), conjugated to the cytotoxic tubulysin TAM470, with potential antineoplastic activity. Upon administration of anti-FAP ADC OMTX705, the anti-FAP monoclonal antibody moiety targets and binds to FAP expressed on cancer-associated fibroblasts (CAFs) in the tumor stroma. Upon binding, internalization and linker cleavage, the cytotoxic moiety is released, which binds to tubulin and inhibits microtubule polymerization. This results in G2/M phase arrest and the apoptosis of FAP-expressing CAFs. FAP, a membrane-bound serine protease overexpressed on CAFs, is minimally expressed on normal, healthy cells.