CPO301

CPO301, also known as SYS6010 in China, is an investigational **EGFR-targeting antibody-drug conjugate** developed by CSPC Pharmaceutical Group and clinically advanced in the United States by Conjupro Biotherapeutics. The molecule comprises a humanized anti-EGFR IgG1 monoclonal antibody optimized from cetuximab, a cleavable Gly-Gly-Phe-Gly tetrapeptide linker, and the topoisomerase I inhibitor payload JS-1, with a reported drug-to-antibody ratio of 8. Following binding to EGFR-expressing tumor cells and internalization, intracellular linker cleavage releases JS-1, causing topoisomerase I-mediated DNA damage and apoptosis. CPO301 is being developed across EGFR-expressing solid tumors, including non-small cell lung cancer, esophageal squamous cell carcinoma, breast cancer, head and neck squamous cell carcinoma, and nasopharyngeal carcinoma.