Clofarabine is a chemotherapy drug that is given as a treatment for some types of cancer. It is mainly used to treat children with acute lymphoblastic leukaemia (ALL) that has come back (relapsed) after initial treatment. This information describes clofarabine, how it is given, and some of its possible side effects. It should ideally be read with our general information about chemotherapy and about your type of cancer or leukaemia.

If you have any further questions you can ask your doctor or nurse at the hospital where you are having your treatment, or speak to one of our cancer support service nurses.

Clofarabine is a colourless fluid.

Clofarabine is given as a drip (infusion) through a fine tube (cannula) inserted into the vein. It may also be given through a central line, which is placed under the skin into a vein near the collarbone, or into a PICC line, which is inserted into a vein in the crook of the arm. The infusion usually takes about two hours.

Chemotherapy is usually given as a course of several sessions (or cycles) of treatment over a few months. Clofarabine is usually given every day for five days, and repeated every two to six weeks. Your nurse or doctor will discuss your treatment plan with you.

Each person’s reaction to chemotherapy is different. Some people have very few side effects, while others may experience more. The side effects described here will not affect everyone who is given clofarabine, and may be different if you are having more than one chemotherapy drug.

We have outlined the most common side effects and some of the less common ones, so you can be aware of them if they occur. However, we have not included those that are very rare and therefore extremely unlikely to affect you.

If you notice any effects which you think may be due to the drug, but which are not listed in this information, please discuss them with your doctor or chemotherapy nurse.

Feeling sick (nausea) and being sick (vomiting) You may begin to feel sick a couple of hours after the treatment is given, but this does not usually last long. Your doctor can prescribe very effective anti-sickness (anti-emetic) drugs to prevent, or greatly reduce, nausea and vomiting. If the sickness is not controlled, or continues, tell your doctor; they can prescribe other anti-sickness drugs which may be more effective. Some anti-sickness drugs can cause constipation. Let your doctor or nurse know if this is a problem.

Lowered resistance to infection Clofarabine can reduce the production of white blood cells by the bone marrow, making you more prone to infection. This effect can occur from the start of treatment and your resistance to infection may remain low for up to four weeks after the chemotherapy. Your immune system may not recover completely for many months after the treatment has finished. Your leukaemia can also make 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 regular blood tests to see how well your bone marrow is working. Occasionally it may be necessary to delay your treatment if the number of blood cells (the blood count) is still low.

Bruising or bleeding Clofarabine 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, or bleeding gums.

Anaemia (low number of red blood cells) While having treatment with clofarabine you may become anaemic. This can make you feel tired and breathless. Let your doctor or nurse know if these symptoms become difficult to cope with.

Headaches Your doctor or nurse can give you painkillers to relieve this.

Diarrhoea This can usually be easily controlled with medicine but let your doctor know if it is severe or if it continues. It is important to drink plenty of fluids if you have diarrhoea.

Loss of appetite A dietitian or specialist nurse at your hospital can give advice.

Tiredness and a general feeling weakness You may feel very tired. It is important to allow yourself plenty of time to rest.

Raised levels of uric acid in the blood Clofarabine can kill the leukaemic cells quickly and this can lead to an increase in the amount of a chemical called uric acid in the body. You may be given a drug called allopurinol to stop this happening. It may also help to drink plenty of fluids and you may be given infusions (drips) of fluid while you have the chemotherapy. While you are taking clofarabine, your uric acid levels will be checked regularly by blood tests.

Your liver may be temporarily affected Clofarabine may cause changes in the way that your liver works, although this will return to normal when the treatment is finished. This is very unlikely to cause you any harm, but your doctor will keep a check on things. Samples of your blood will be taken from time to time to check your liver is working properly.

Soreness and redness of the palms of the hands and soles of the feet (Sometimes known as palmar planter or hand and foot syndrome) This is temporary and usually improves in a few days.

Your kidneys may be temporarily affected This is unlikely to cause any symptoms. Your doctor may check how well your kidneys are working, using blood or urine tests.

Acute inflammatory response Signs of an acute inflammatory response to clorfarabine include a high temperature (fever), weight gain, a low blood pressure and shortness of breath. You will be closely monitored while you have this drug, but if you notice any symptoms that concern you, let you nurse or doctor know straight away.

Sore mouth and ulcers Your mouth may become sore or you may notice small ulcers. Drinking plenty of fluids, and cleaning your teeth regularly and gently with a soft toothbrush, can help to reduce the risk of this happening. Tell your nurse or doctor if you have any of these problems, as special mouthwashes and medicines can be prescribed to prevent or clear any mouth infection.

You may notice that your food tastes different. Normal taste will usually come back after the treatment finishes.

Risk of blood clots Cancer can increase your risk of developing a blood clot (thrombosis), and having chemotherapy may increase this risk further. A blood clot may cause symptoms such as pain, redness and swelling in a leg, or breathlessness and chest pain. Blood clots can be very serious so it is important to tell your doctor straightaway if you have any of these symptoms. However, most clots can usually be successfully treated with drugs to thin the blood. Your doctor or nurse can give you more information.

Other medicines Some medicines can be harmful to take when you are having chemotherapy. Let your doctor know about any medicines 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 taking clofarabine. 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 taking clofarabine, as the developing foetus may be harmed. It is important to use effective contraception while taking the drug, and for at least a few months afterwards. Again, discuss this with your doctor.

This section is based on our Clofarabine factsheet which has been compiled using information from a number of reliable sources, including:

• Sweetman et al (Eds.). Martindale: The Complete Drug Reference (33rd edition). Pharmaceutical Press. 2002.
• The Medicines.org.uk website - www.medicines.org.uk (November 2007).
• Perry (Ed). The Chemotherapy Source Book (3rd edition). Williams and Wilkins, Lippincott. 2001.
• The National Cancer Institute www.cancer.gov (April 2006).

For further references, please see general bibliography.