MabCampath (Alemtuzumab)

How does it work?

MabCampath infusion contains the active ingredient alemtuzumab, which is a type of medicine known as a monoclonal antibody. It is used to treat a type of cancer of the white blood cells called chronic lymphocytic leukaemia (CLL).

CLL is the commonest form of leukaemia. It occurs when the bone marrow, for some reason, begins to produce excessive numbers of abnormal white blood cells called B lymphocytes.

Alemtuzumab acts by attacking the abnormal B lymphocytes. It works in a similar way to the natural antibodies produced by our immune system. Our natural antibodies recognise foreign invaders and bind to them, helping our immune systems to attack them and protect us from infections. Monoclonal antibodies like alemtuzumab are made in laboratories. They are designed to attack particular proteins in a similar way.

Alemtuzumab specifically recognises and binds to a protein called CD52, which is found on the surface of the abnormal B lymphocytes. This triggers the immune system to attack the abnormal B lymphocytes. Unfortunately it also causes the immune system to attack the healthy B cells, because these also carry the CD52 protein. This can leave people susceptible to infection. However, the body quickly replaces any healthy cells that are damaged by the treatment.

Alemtuzumab is given by a drip into a vein (intravenous infusion). Some people can have a severe allergic reaction to the medicine (see warning below), so to reduce the chance of this each drip will usually be given over about two hours. You will also usually be given some painkillers, antihistamine and possibly steroids before the drip to help prevent a reaction. If you do have a reaction, your next drip will be given over a longer period of time.

During the first week of treatment the drip will be given in increasing doses on days one, two and three, providing this is well tolerated. This is called dose escalation. After this initial treatment, the drip will usually be given three times a week, on alternate days, for up to 12 weeks.

What is it used for?

  • B-cell chronic lymphocytic leukaemia (B-CLL).


  • You may experience infusion related reactions during early treatment with this medicine. These may include shortness of breath, fever, chills, nausea, vomiting, rash, itching, headache, diarrhoea and a fall in blood pressure. The reactions are caused by molecules called cytokines that are released when the B lymphocytes are destroyed by this medicine. Any reactions are usually mild to moderate in severity, but can sometimes be more serious. You will be monitored closely during your treatment, but it is very important to tell your nurse or doctor if you get these or any other symptoms. Infusion related reactions usually occur during the first ‘dose-escalation’ week of treatment and then get less severe with further doses. If you get severe reactions your dose won’t be increased until they reduce. This is to allow your body to get used to the medicine.
  • You will need regular blood tests to monitor your blood cells during treatment with this medicine.
  • This medicine can lower the number of healthy white blood cells in your blood and so can increase your risk of getting infections. For this reason, you will be given preventative antibiotic and antiviral medicines during your treatment and for at least two months after your treatment has finished. They should be continued until your blood cells have recovered. You should tell your doctor immediately if you get any signs of infection during your treatment or after it has finished, for example a high temperature (fever), sore throat, mouth ulcers or swollen glands, so that your blood cells can be checked and treatment given if necessary. If your white blood cells fall too low or you get a severe infection your treatment may need to be stopped until this has resolved.
  • This medicine can also decrease the numbers of blood cells called platelets in your blood, which can cause problems with blood clotting. Tell your doctor if you experience any unexplained bruising or bleeding, or purple spots in your skin during your treatment.
  • It is not known if alemtuzumab can affect reproductive ability, or if it can harm a developing baby when given during pregnancy. However, because it could potentially cross the placenta and attack the blood cells of a developing foetus, women who could get pregnant must use an effective method of contraception to avoid pregnancy and men must use an effective method of contraception to avoid fathering a child, both during treatment and for six months after treatment with this medicine is finished.

Use with caution in

  • People over 65 years of age.
  • Heart disease caused by inadequate blood flow to the heart (ischaemic heart disease), eg angina.
  • People taking medicines for high blood pressure (antihypertensives).
  • People who have previously been treated with chemotherapy that can have side effects on the heart.

Not to be used in

  • Allergy to mouse protein.
  • HIV infection.
  • Active severe infections.
  • Active secondary malignancies.
  • Pregnancy.
  • Breastfeeding.
  • This medicine is not recommended for children under 17 years of age.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.

If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • It is not known if alemtuzumab can affect reproductive ability, or if it can harm a foetus when given during pregnancy. However, because it could potentially cross the placenta and attack the B cells of a developing foetus, it should not be given to pregnant women. Women who could get pregnant must use an effective method of contraception to prevent pregnancy and men must use an effective method of contraception to avoid fathering a child, both during treatment and for six months after the last infusion. Seek further medical advice from your doctor. If you think you could be pregnant you should inform your doctor immediately.
  • It is not known if this medicine passes into breast milk. However, because it may pass into breast milk and harm a nursing infant, it should not be given to women who are breastfeeding. Women who have been treated with this medicine should not breastfeed for at least four weeks after their last infusion. Seek medical advice from your doctor.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.

  • Increased susceptibility to infections.
  • Decreased number of white blood cells, platelets or red blood cells in the blood.
  • Headache.
  • Loss of appetite and weight loss.
  • Decrease or increase in blood pressure.
  • Shortness of breath, coughing.
  • Disturbances of the gut, such as nausea, vomiting, diarrhoea, abdominal pain, constipation, indigestion.
  • Skin reactions such as rash or itching.
  • Fever.
  • Fatigue.
  • Increased sweating.
  • Pain in various parts of the body (muscles, back, chest, bones, joints).
  • Sore mouth.
  • Thirst.
  • Flushing.
  • Sleepiness.
  • Depression.
  • Confusion.
  • Dizziness.
  • Pins and needles or numb sensations.
  • Bleeding from the stomach or intestines.
  • Heart disorders, such as increased heart rate (tachycardia), abnormal heart beats (arrhythmias), heart attack or heart failure.

The side effects listed above may not include all of the side effects reported by the drug's manufacturer.

For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

This medicine is not known to significantly affect any other medicines. However, you should always tell your doctor if you are taking any other medicines, including over-the-counter and herbal medicines, before treatment with this medicine is started. Similarly, always seek advice from your doctor or pharmacist before taking any new medicines while you are receiving treatment with this medicine, so they can check that the combination is safe.

The manufacturer recommendeds that treatment with this medicine is not given within three weeks of other anti-cancer medicines.

As this medicine attacks your B cells, which are part of your immune system, it may make it hard for your body to produce antibodies. This means that vaccines may potentially be less effective if given during treatment, and live vaccines may cause serious infections. For this reason, if you need to have any vaccinations, these should preferably be completed a few weeks before your first infusion. Live vaccines should not be given during your treatment, or for 12 months after it is finished. Live vaccines include measles, mumps, rubella, MMR, oral typhoid and yellow fever.

Other medicines containing the same active ingredient

There are currently no other medicines available in the UK that contain alemtuzumab as the active ingredient.