Cetuximab is an anticancer drug that inhibits the epidermal growth factor receptor (EGFR) which is present on the surface of some kinds of cancer cells.
A protein that occurs naturally in the body called epidermal growth factor (EGF) usually binds to EGF receptors and stimulates the cancer cells to grow and proliferate.
Cetuximab is a monoclonal antibody that binds to these receptors before EGF does, therefore preventing the growth of the cancer cells.
Some of the approved clinical indications cetuximab may be used for include:
Squamous cell carcinoma of the head and neck
Cetuximab is commonly used alongside platinum-based chemotherapy as a first line approach to cancer that has spread or is recurring. It may also be used as an adjuvant to radiation therapy in localized disease.
Advanced Bowel cancer or cancer of the colon and rectum
Patients with metastatic colorectal cancer that expresses EGFR may be treated with cetuximab in combination with chemotherapy. Cetuximab may also be given as a single therapy to patients who have failed to respond to irinotecan and oxaliplatin based regimens.
However, the drug is ineffective in individuals who have a mutation in the KRAS gene rather than normal or “wild type” KRAS. In around 40% of cases, people with bowel cancer have a KRAS mutation meaning doctors need to test a sample of the tumor for mutation before beginning cetuximab therapy.