DR319-DP

DR319-DP is a preclinical, glycosite-specifically conjugated **Nectin-4/Trop-2 bispecific dual-payload antibody-drug conjugate** co-developed by Doer Bio and Glyco-therapy. Its underlying DR319 antibody uses a 1+1 avidity-driven design comprising an anti-Nectin-4 monoclonal-antibody arm and a low-affinity, high-avidity anti-Trop-2 VHH arm, intended to preferentially bind Nectin-4/Trop-2 double-positive tumor cells while reducing binding to single-positive normal cells. DR319-DP carries a topoisomerase I inhibitor payload at drug-to-antibody ratio 4 and the microtubule inhibitor monomethyl auristatin E at drug-to-antibody ratio 2, providing orthogonal cytotoxic mechanisms intended to improve tumor killing, bystander activity, and resistance coverage in solid tumors. Publicly reported evidence is limited to preclinical CDX and PDX models. ([aacrjournals.org](https://aacrjournals.org/cancerres/article/86/7_Supplement/4541/779683/Abstract-4541-DR319-DP-A-Nectin-4-Trop-2))