RG 83852

RG 83852 is a murine monoclonal antibody that preferentially inhibits the high-affinity binding of epidermal growth factor (EGF) to its receptor, the epidermal growth factor receptor (EGFR). It acts as an antagonist at EGFR, impeding ligand binding. Unlike other anti-EGFR monoclonal antibodies, RG 83852 does not directly inhibit EGFR tyrosine kinase activity and may be partially agonistic; evidence from clinical studies indicates that it achieves high EGFR receptor saturation in tumors and skin without producing the typical EGFR-inhibitor rash. Developed by Sanofi, it was investigated as a potential anticancer agent, specifically for neoplasms overexpressing EGFR, including non-small cell lung cancer (NSCLC) and head and neck cancers. Clinical development was discontinued after phase 1 trials, having demonstrated safety and effective receptor occupancy but limited efficacy[1][2][3][5].