Gemtuzumab (Mylotarg®)
This information is about a drug called gemtuzumab (pronounced gem-to-zoo-mab), which is also known as Mylotarg® (my-lo-targ). Mylotarg is a type of cancer drug known as a monoclonal antibody. It is mainly used as part of research trials to treat some types of acute myeloid leukaemia (AML). At present it has not been approved for use outside of clinical trials in the UK, so it is not generally available.
- Monoclonal antibodies
- How Mylotarg works
- What it looks like
- How it is given
- Possible side effects
- Additional information
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 that are found on the surface of some cancer cells. The monoclonal antibody recognises the protein and locks onto it (like a key in a lock). Mylotarg locks onto a specific protein called CD33, which is found on the surface of leukaemia cells and certain developing white blood cells (myeloid cells). Sometimes monoclonal antibodies have a cancer drug attached to them. They can then be used to deliver treatment directly to the cancer cells (targeted therapy).
How Mylotarg works
Mylotarg is a type of targeted therapy. It carries a chemotherapy drug called ozogamicin (o-zo-gam-i-sin) directly to the cancer cells. As the chemotherapy is only delivered to cells showing the CD33 protein it may not affect normal cells within the body.
What it looks like
Mylotarg is a colourless fluid after being diluted.
How it is given
Mylotarg is given as a drip (infusion) into a vein (intravenously) through a fine tube inserted into the vein (cannula). It can also be given through a central line, which is inserted under the skin into a vein near the collarbone, or through a PICC line, which is inserted into a vein in the crook of your arm.
Each infusion is given over approximately two hours. As the best way to give Mylotarg is not yet known, the number of doses and how often they are given will be decided by your doctor. Mylotarg is sensitive to light and is protected from the light when being given.
Possible side effects
Each person's reaction to a cancer drug is different. Some people have few side effects, while others may experience more. We have outlined the most common side effects, so that you are aware of them. We have not included those that are rare, however, and which are therefore extremely unlikely to affect you. If you do notice any effects which you think may be due to the drug, but which are not listed here, please discuss them with your doctor or nurse.
Allergic reaction It is possible to have an allergic reaction to Mylotarg (usually during the infusion or within two hours of receiving it). Signs of a reaction include skin rashes and itching, a feeling of swelling of the tongue or throat, irritation of the nasal passages, wheezing, a cough and breathlessness. You will be monitored closely during and after your treatment, but it is very important to tell your nurse or doctor if you have any of these effects. To reduce the chance of developing an allergic reaction, anti-allergy drugs are given before the infusion and may also be repeated afterwards.
Nausea and vomiting Your doctor can now prescribe very effective anti-sickness drugs to prevent or reduce nausea and vomiting. If nausea or sickness is not controlled or if it continues, your doctor can prescribe other anti-sickness drugs which may be more effective.
Flu-like symptoms This can include a high temperature, chills, weakness, sweating, muscle aches, tiredness, dizziness and headache. These effects generally occur after the infusion. If necessary, your doctor will give medicines to control these effects.
High or low blood pressure This may happen during or after the infusion. Your blood pressure will be monitored during the infusion and for a while afterwards.
Sore mouth Your mouth may become sore or dry, or you may notice small ulcers. Drinking plenty of fluids and cleaning your teeth regularly and gently with a soft toothbrush may help to reduce the risk of this happening. Tell your doctor or nurse if you have any of these problems. Your doctor can prescribe special mouthwashes and medicine to prevent or clear any mouth infection.
Taste change You may notice that your food tastes different. Normal taste will come back after the treatment finishes.
Lowered resistance to infection Mylotarg can reduce the production of white blood cells by the bone marrow, making you more prone to infection.
Contact your doctor or the hospital straightaway if:
- Your temperature goes above 38ºC (100.5ºF)
- You suddenly feel unwell (even with a normal temperature).
You will have a blood test before having more treatment to make sure that your cells have recovered. Occasionally it may be necessary to delay your treatment if the number of blood cells (the blood count) is still low.
Bruising or bleeding Mylotarg can reduce the production of platelets (which help the blood to clot). Let your doctor know if you have any unexplained bruising or bleeding, such as nosebleeds, blood spots or rashes on the skin, and bleeding gums.
Anaemia (low number of red blood cells) While having treatment with Mylotarg you may become anaemic. This may make you feel tired and short of breath.
Effects on the liver Mylotarg may cause changes in the way your liver works. This may not cause you any harm, but your doctor will monitor this closely by taking samples of your blood from time to time to measure your liver function.
Additional information
Some medicines can be harmful to take when you are having chemotherapy. Let your doctor know about any medications you are taking, including non-prescribed drugs such as complementary therapies and herbal drugs.
Fertility Your ability to become pregnant or father a child may be affected by this treatment. It is important to discuss fertility with your doctor before starting treatment.
Contraception It is not advisable to become pregnant or father a child while having this treatment, as the developing foetus may be harmed. It is important to use effective contraception while taking this drug, and for at least a few months afterwards. Again, discuss this with your doctor or nurse.
