anti-TROP2 antibody-drug conjugate OBI-992

An antibody-drug conjugate (ADC) composed of a monoclonal antibody directed against the tumor-associated antigen (TAA) trophoblast cell surface protein 2 (trophoblast antigen 2; calcium signal transducer 2; TROP2; TROP-2; TACSTD2; GA733-1; M1S1), conjugated to a topoisomerase-1 inhibitor (TOP1i; TOP-Ii) via a hydrophilic, enzyme-cleavable linker, with potential antineoplastic activity. Upon administration of anti-TROP2 ADC OBI-992, the anti-TROP2 antibody moiety targets and binds to TROP2 expressed on tumor cells. Upon binding, internalization and linker cleavage, the TOP1i moiety is released, binds to TOP1 and inhibits DNA topoisomerase I activity, thereby inhibiting DNA replication and resulting in cell cycle arrest and tumor cell apoptosis. This inhibits the proliferation of TROP2-expressing tumor cells. TROP2 is a transmembrane protein overexpressed in various tumors. Its expression is associated with enhanced tumor aggressiveness, metastasis, drug resistance and increased tumor cell survival.