EGFR (domain III) and CDCP1 (bispecific)

Class

Bispecific antibody-drug conjugate (vcMMAE payload)

Pathway

EGFR signaling blockade plus CDCP1-restricted tumor-selective payload delivery

This mechanism combines two proteins on the surface of certain cancer cells into a single therapeutic target. Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that drives cell growth signaling when activated by its ligands; blocking domain III, the ligand-binding region, prevents receptor activation. CDCP1 (CUB domain-containing protein 1) is a transmembrane protein whose expression is comparatively restricted to tumor tissue and associated with invasive behavior. A bispecific antibody engineered to bind both proteins serves two purposes: it can dampen EGFR-driven proliferative signaling, and, because it is built as an antibody-drug conjugate carrying a cytotoxic payload (monomethyl auristatin E, delivered via a cleavable valine-citrulline linker), it also delivers a cell-killing agent selectively into cells expressing both markers together. Requiring co-expression of EGFR and CDCP1 for efficient uptake is intended to sharpen tumor selectivity, since EGFR alone is also present on healthy epithelial tissue such as skin and gut lining. This general approach - pairing a signaling-blocking arm with a tumor-restricted targeting arm on one conjugate - is relevant across epithelial cancers where EGFR pathway activity contributes to growth but ordinary EGFR-directed therapies risk toxicity to normal tissue.