Cetuximab (Erbitux®)
This information is about cetuximab (pronounced se-tux-e-mab), which is a drug used to treat people with cancer of the large bowel (colon and rectum). Cetuximab may also be used to treat other types of cancer as part of a research trial.
- What is cetuximab?
- Monoclonal antibodies
- How cetuximab works
- What it looks like
- How it is given
- Possible side effects
What is cetuximab?
Cetuximab is a type of drug known as a monoclonal antibody. In the UK it is currently used to treat cancer of the large bowel (colon and rectum) that has come back after initial treatment and has spread to other parts of the body (advanced or metastatic cancer). Cetuximab is given in combination with the drug irinotecan.
It is also being used in research trials to treat other types of cancer, including non-small cell lung cancer (NSCLC) and cancer of the head and neck. You may also be offered it as part of an early trial for other types of cancer.
Cetuximab is mainly given alongside chemotherapy, although it may be given on its own or with radiotherapy as part of a research trial.
Monoclonal antibodies
Monoclonal antibodies are used to try to destroy some types of cancer cells while causing little harm to normal cells. They are designed to recognise certain proteins (receptors) that are found on the surface of particular cancer cells.
Such receptors are known as epidermal growth factor receptors or EGFRs. When growth factors (such as transforming growth factor alpha and epidermal growth factor) bind to the receptor, the cancer cell is stimulated to grow, divide and spread.
How cetuximab works
Cetuximab attaches itself to the EGFRs and prevents the receptors from being activated. This stops the cells from dividing. It therefore has the potential to stop the cancer cells from growing. It works in a different way from both chemotherapy and hormonal therapy.
Cetuximab may also make the cancer cells more sensitive to chemotherapy.
Tests may be done to find the level of EGFR in the body before cetuximab is given. This can help the doctors to know whether you are likely to benefit from this treatment. Testing can be done at the same time as diagnosis of the cancer, or samples of cancer cells from previous biopsies or surgery may be used.
How it is given
Cetuximab is given by a drip into the vein (intravenously) through a fine tube (cannula) inserted into a vein. The first dose is given slowly, usually over two hours. After this, doses are given weekly and this normally takes about an hour. The first dose is usually larger than the weekly maintenance treatments. You may be given other medicines before cetuximab to lessen the side effects during treatment.
Possible side effects
Each person's reaction to a cancer drug is different. Some people have very few side effects, while others may experience more. If you notice any effects which you think may be due to the drug, but which are not listed here, please discuss them with your doctor.
The side effects of cetuximab are generally mild and some of these can be reduced with medicines. Cetuximab is given with the chemotherapy drug irinotecan, so many of the side effects you might have will be caused by the irinotecan. Cetuximab does not increase the side effects of irinotecan.
Allergic reactions Signs of a reaction include skin rashes and itching, a feeling of swelling in the tongue or throat, irritation of the nasal passages, wheezing, a cough and breathlessness. You will be monitored closely during your treatment, but tell your nurse or doctor if you have any of these symptoms. To reduce the chance of developing an allergic reaction, certain drugs (antihistamines) can be given before the infusion. The drip can also be slowed down or stopped until the reaction is over.
Skin changes Mild skin rashes are very common. They begin during the first two weeks of treatment and usually go away completely when the treatment ends. Some people have more severe skin changes, which can include reddening of the skin, and red pimples and spots (like acne) on the face. The skin of the face may become flaky and scaly. Some people have dry skin, eczema on their fingertips, elbows and extremities, which is sore and itchy. If you have any of these skin changes, let your doctor know straight away. If you have very severe skin problems the length of time between treatments may be extended or the dose may be lowered.
Treatment can be prescribed by your doctor to reduce the rash. To help reduce the reddening, it is best to avoid foods that make the skin go red, such as chillies and alcohol.
To help reduce dry skin eczema, it is helpful to avoid things that make your skin dry, such as too much central heating and soap. Your doctor can prescribe creams to moisturise your skin.
Breathlessness Some people may become breathless. This is more likely if you have an existing lung problem. Let your doctor know if you notice any increase in breathlessness.
Nausea (feeling sick) and less commonly vomiting Your doctor can now prescribe very effective anti-sickness (anti-emetic) drugs to prevent or greatly reduce nausea and vomiting. If the sickness is not controlled, or if it continues, tell your doctor, who can prescribe other anti-sickness drugs which may be more effective.
Diarrhoea This can usually be controlled with medicine, but tell your doctor if it is severe or if it continues. It is important to drink plenty of fluids if you have diarrhoea.
Fever and chills If you develop a fever or chills let your doctor know.
Sore eyes You may notice that your eyes become sore, red and itchy. This is known as conjunctivitis and your doctor can prescribe eye drops to help.
