A type of monoclonal antibody being studied in the diagnosis and treatment of cancer. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

Cetuximab (marketed under the name Erbitux) is a chimeric monoclonal antibody, an EGFR inhibitor, given by intravenous injection for treatment of metastatic colorectal cancer and head and neck cancer. Cetuximab was discovered by Imclone Systems and is distributed in North America by ImClone and Bristol-Myers Squibb, while in the rest of the world distribution is by Merck KGa A.