Gilteritinib (Xospata)
Gilteritinib is a type of targeted cancer drug. You pronounce it as gil-teh-rih-tih-nib.
It’s a treatment for acute myeloid leukaemia (AML) that isn’t responding to treatment. This is called refractory AML. Or it can be used for AML that has come back after treatment has finished. This is called relapsed AML.
You have it on its own.
You have gilteritinib for AML if your cancer has a 
in the FLT3 . Your doctor will check for this mutation before you can start this drug.
How does gilteritinib work?
Gilteritinib is a type of cancer growth blocker called a tyrosine kinase inhibitor (TKI).
Tyrosine kinase inhibitors block chemical messengers (enzymes) called tyrosine kinases. Tyrosine kinases help to send growth signals in cells, so blocking them stops the cell from growing and dividing.
How do you take gilteritinib?
You take gilteritinib as tablets. You swallow them whole with a glass of water. You take the tablets with or without food. You should not crush or chew the tablets.
You should take the right dose, not more or less.
Talk to your healthcare team before you stop taking a cancer drug, or if you miss a dose.
How often do you take gilteritinib?
You take gilteritinib once a day. You continue taking gilteritinib for as long as it's working and you are not experiencing too many side effects. Or you continue taking gilteritinib until:
- your AML is in
remission - you have a
stem cell transplant
Tests
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.
You also have heart tests such as an ECG before and during treatment.
What are the side effects of gilteritinib?
Side effects can vary from person to person. They also depend on what other treatments you're having.
When to contact your team
Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:
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you have severe side effects
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your side effects aren’t getting any better
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your side effects are getting worse
Early treatment can help manage side effects better.
Contact your advice line 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. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.
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:
Dizziness
This drug might make you feel dizzy. Don’t drive or operate machinery if you have this.
Low blood pressure
Tell your doctor or nurse if you feel lightheaded or dizzy. You have your blood pressure checked regularly.
Cough and breathlessness
Gilteritinib can cause a cough or breathlessness. Less commonly, a cough might be a sign of differentiation syndrome. Differentiation syndrome is when you have a fast release of immune substances () into your blood. It needs to be treated quickly as it can be life threatening.
Tell your doctor or nurse straight away if you have a cough or breathlessness that is not normal for you.
Diarrhoea
Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.
Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables.
Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.
Constipation
is easier to sort out if you treat it early. Drink plenty and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can give you a laxative if needed.
Feeling sick (nausea)
Feeling sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.
It is important to take anti sickness medicines as directed by your doctor or pharmacist, even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.
Liver changes
You might have liver changes while taking this drug. You have regular blood tests to check for any changes in the way your liver is working.
Muscle weakness, spasms and pain
Let your doctor or nurse know if you have any weakness, spasms or pain in your muscles during or after having treatment.
Your blood tests might show that you have high levels of an enzyme in your blood called creatinine phosphokinase (CPK). This is mainly found in the heart, brain or skeletal muscles.
Your doctor might do a blood test to check why you might have chest pain, muscle aches or pains, muscle tenderness or weakness.
Pain in your joints, arms or legs
You might feel some pain in your joints, arms or legs. Speak to your doctor or nurse about what painkillers you can take to help with this.
Tiredness and weakness (fatigue)
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.
Swollen hands and feet
Swelling of hands and feet is due to fluid build up. This is called oedema. Let your doctor or nurse know if you have any swelling.
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:
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an allergic reaction to the drug - symptoms include a skin rash, itching, swelling of the lips, face or throat, breathing difficulties, fever and chills
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heart problems - symptoms may include chest pain, feeling shivery, high temperature, feeling lightheaded or faint, breathless, swelling in the tummy, legs or ankles. Or you may have changes to how fast your heart beats
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kidney problems - symptoms might include passing less wee or swollen legs. Let your healthcare team know if you have these symptoms
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generally feeling unwell (malaise)
Coping with side effects
We have more information about side effects and tips on how to cope with them.
What else do you need to know?
Other medicines, foods and drink
Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.
Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.
Pregnancy and contraception
This treatment might harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment.
Women must not become pregnant for at least 6 months after the end of treatment. It is unknown if gilteritinib interferes with hormonal contraceptives such as the pill. So doctors advise women to add a barrier method such as condoms as a second form of contraception.
Men should not get someone pregnant for at least 4 months after treatment.
Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner falls pregnant while having treatment.
Loss of fertility
It is not known whether this treatment affects in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.
Breastfeeding
It is not known whether these drugs come through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment and for 2 months afterwards.
Other conditions
If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.
Immunisations
Don’t have immunisations with live vaccines 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 one of the shingles vaccines called Zostavax.
You can have:
- other vaccines, but they might not give you as much protection as usual
- the flu vaccine (as an injection)
- the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment
Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your recovers from treatment.
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. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.
If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. 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.
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.
