Duality Biologics (Suzhou) Co. Ltd. has presented data describing the discovery and preclinical results of DB-1303, an antibody-drug conjugate containing a trastuzumab biosimilar targeting HER2 (BAT0606), an exatecan derivative payload with topoisomerase I inhibitory activity (P1003) and an enzymatic ally cleavable tetrapeptide-maleimide-linker (payload-linker named L101P1003).