EGFR targeted therapy in non-small cell lung cancer: potential role of cetuximab

Chemotherapy alone has limited ability to significantly improve survival in non-small lung cancer (NSCLC) beyond what has already been achieved. The epidermal growth factor (EGF) pathway plays a vital role in the pathogenesis and progression of NSCLC. Two classes of drugs inhibit the EGF receptor (EGFR) pathway: small molecules that inhibit the intracellular tyrosine kinase activity of the receptor, and monoclonal antibodies that target the extracellular domain in the ligand-binding region. Cetuximab is a human - mouse chimeric immunoglobulin G1 class monoclonal antibody directed against EGFR. Preclinical studies with cetuximab suggested that there was inhibition of growth of human NSCLC cell lines. Cetuximab is currently the focus of intense investigation in various patient populations with NSCLC. This review focuses on clinical trials of cetuximab in NSCLC and identifies future directions with this agent.