Inotuzumab ozogamicin (Besponsa)

Inotuzumab ozogamicin is a type of targeted cancer drug. It is a treatment for a type of acute lymphoblastic leukaemia (ALL) called B cell precursor ALL. You might have it if the leukaemia has come back (relapsed) or not responded to treatment (refractory).

Inotuzumab ozogamicin is pronounced in-oh-too-zoo-mab oh-zoh-ga-my-sin. It's often called inotuzumab for short.

How inotuzumab works

Inotuzumab is a type of targeted cancer drug called a monoclonal antibody (MAB). It finds the leukaemia cells by targeting a certain protein on them. This protein is called CD22. It then delivers the drug directly into the leukaemia cells and kills them. 

How you have inotuzumab

You have inotuzumab as a drip into your bloodstream (intravenously).

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

  • central line
  • PICC line
  • portacath

If you don't have a central line

You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.

When you have inotuzumab

You have inotuzumab in cycles. This means that you have the drug and then a rest to allow your body to recover.

You have it over one hour every week for 3 weeks. This is one cycle.

You have up to 6 cycles of inotuzumab. If you have inotuzumab before a stem cell transplant you have 2 or 3 cycles.


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Side effects

How often and how severe the side effects are can vary from person to person. They also depend on what other treatment you are having. 

This treatment affects the immune system. This may cause inflammation in different parts of the body which can cause serious side effects. They could happen during treatment, or some months after treatment has finished. In some people, these side effects could be life threatening.

When to contact your team

Your doctor, pharmacist or nurse will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects
  • your side effects aren’t getting any better
  • your side effects are getting worse

Early treatment can help manage side effects better. 

Contact your healthcare team immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Increased risk of infection 

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Bruising, bleeding gums, or nose bleeds

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

You're also at risk of bleeding from other areas of the body. Contact your advice line straight away if you notice blood in your poo (stool) or sick (vomit).

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Loss of appetite

You might lose your appetite for various reasons while having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.


Let your doctor or nurse know if you have headaches. They can give you painkillers such as paracetamol to help.

Tummy (abdominal) pain 

Tell your doctor or nurse if you have this. They can check for the cause of the pain and give you medicine to help. 

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, try eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.

Diarrhoea or constipation 

Tell your healthcare team if you have diarrhoea or constipation. They can give you medicine to help. 

Sore mouth and lips

You might get a sore mouth and lips. You’ll have mouth washes to keep your mouth healthy. Use lip balm to keep your lips moist.

You can have painkillers to reduce the soreness. Take them half an hour before meals to make eating easier. Tell your doctor or nurse if your mouth and lips are sore.

Liver changes

You might get liver changes. Your doctor might pick these up from blood tests or you might have symptoms such as yellowing of the skin and whites of the eyes (jaundice).

You have regular blood tests to check for any changes in the levels of chemicals produced by the liver.


Tiredness and weakness (fatigue) can happen during and after treatment. Doing gentle exercises each day can keep your energy up. Don't push yourself, rest when you start to feel tired and ask others for help.

Infusion related reaction 

You may have a reaction to inotuzumab while you are having the drug or shortly afterwards. Symptoms include fever, chills, skin rash, facial swelling or difficulty breathing. 

You have medicines beforehand to try to prevent a reaction. Tell your nurse straight away if you have any symptoms of an allergic reaction. They will slow down or stop your drip for a while.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • high levels of chemicals in your blood due to the breakdown of tumour cells - you will have regular blood tests to check for this
  • high levels of uric acid in the blood that might cause kidney changes and swollen joints (gout)
  • a build up of fluid in your tummy (ascites) or swelling of your tummy
  • blocked or damaged blood vessels in the liver due to blood clots (veno occlusive disease) – symptoms include fast weight gain, fluid build up in your tummy (abdomen), enlarged liver and yellowing of the skin and whites of the eyes
  • changes to your heart rhythm usually picked up on an electrocardiogram (ECG) – tell your nurse or doctor if you feel lightheaded or dizzy
  • high levels of enzymes called amylase and lipase in the blood. They help to digest food. You have regular blood tests to check this
  • allergic reaction causing a rash, shortness of breath, redness, dizziness and swelling of the face

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medicines, foods and drink 

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Loss of fertility 

It is not known whether this treatment affects fertility in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Pregnancy and contraception 

It is unknown whether treatment may or may not harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment. Let your team know straight away if you or your partner become pregnant while having treatment.

Talk to your doctor or nurse about effective contraception you can use during treatment. Ask how long you should use it before starting treatment and after treatment has finished.

Women must avoid becoming pregnant for at least 8 months after their last dose of inotuzumab.

Men must avoid fathering a child for at least 5 months after their last dose of inotuzumab.


Don’t breastfeed during this treatment and for 2 months afterwards. The drug may come through in the breast milk.

Treatment for other conditions

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment. For example, if you need treatment for anything else, including teeth problems.


Don’t have immunisations with live vaccines at least 2 weeks before treatment, while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and the shingles vaccine (Zostavax).

You can:

  • have other vaccines, but they might not give you as much protection as usual
  • have the flu vaccine (as an injection)

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

This page is due for review. We will update this as soon as possible.

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