Sunitinib (Sutent)

Sunitinib is pronounced sue-nit-i-nib. It is a type of biological therapy called a protein kinase inhibitor. Protein kinase is a type of chemical messenger (an enzyme) that plays a part in the growth of cancer cells. Sunitinib blocks the protein kinase to stop the cancer growing. It is also known by its brand name Sutent (pronounced sue-tent).

Sunitinib is a treatment for 

• Advanced kidney cancer
• A rare type of stomach cancer called gastrointestinal stromal tumour (GIST)
• Pancreatic neuroendocrine tumours

Sunitinib comes as capsules. You can take them with or without food.

For kidney cancer and GIST stomach cancer you take sunitinib once a day for 4 weeks and then have a 2 week break, when you don’t take the tablets. This 6 week period is called a cycle of treatment and is repeated for as long as the sunitinib works.

For pancreatic neuroendocrine tumours you take sunitinib once a day without any breaks for as long as it works.

It is very important that you take capsules according to the instructions your doctor or pharmacist gave you. You should take the right dose, not more or less. And never stop taking a cancer drug without talking to your specialist first. If you have accidentally taken too many capsules, talk to your doctor or nurse straight away. If you forget to take your capsules don't take a double dose to make up for a forgotten dose.

The side effects associated with sunitinib are listed below. Remember that most people don’t have all of them. You may have a few of these effects.

More than 10 in every 100 people have one or more of these.

• Tiredness (fatigue) occurs in almost 8 out of 10 people (80%) during and after treatment – most people find their energy levels are back to normal by 6 months to a year after treatment ends
• Diarrhoea happens in around 6 out of 10 people (60%) but this is usually mild – do tell your doctor or nurse as you can be given medicines to control it
• Skin changes – your skin may be drier, become red, or have a rash and 3 out of 10 people (30%) have yellowing of their skin, which goes back to normal once treatment finishes
• Hair colour changes – your hair may become grey while you are having treatment but during the 2 weeks off treatment some colour may come back
• Hands and feet become red and blistered in about 3 out of 10 people (30%)
• A sore mouth occurs in about 1 out of 10 people (10%)
• Raised blood pressure – if your blood pressure goes up you may need to take tablets to control it
• A slower heart rate
• Loss of appetite
• A change in taste in about 1 in 4 people (25%)
• Feeling or being sick happens in about 1 in 3 people (36%)  – this is usually well controlled with anti sickness medicines
• Weight loss
• Indigestion and abdominal pain
• Dizziness
• Headaches
• Weakness
• Constipation – drink plenty of fluids and let your doctor or nurse know if you have this for more than 3 days as you can have laxatives to control it
• A mild effect on the liver and kidneys, which is unlikely cause any symptoms and will almost certainly go back to normal after the treatment finishes – you will have regular blood tests to keep an eye on how your liver and kidneys are working
• Loss of fertility – you may not be able to become pregnant or father a child after treatment with this drug so talk to your doctor before starting treatment if you plan to have a baby in the future
• Swollen hands and feet caused by fluid build up

With this drug, people may have a temporary drop in the number of blood cells made by the bone marrow, leading to the following side effects

• An increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery
• Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
• Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia)

Some of these side effects can be life threatening, particularly infections. Contact your doctor or nurse if you have any of these bone marrow effects. Your doctor will check your blood counts regularly to see how well your bone marrow is working.

Between 1 and 10 in every 100 people have one or more of these.

• Watery eyes from over production of tears – your doctor or nurse can give you eye drops to help
• Nose bleeds
• A drop in the level of thyroid hormones (hypothyroidism) – this may cause tiredness, feeling cold and weight gain. You will have regular blood tests to check your hormone levels
• Chest pain
• Depression
• Piles (haemorrhoids), causing pain in the back passage (rectum)
• Problems swallowing or speaking due to a swollen voice box
• A stuffy nose
• Pain in the back, joints or muscles
• Increased sensitivity to touch in hands and feet
• High levels of uric acid in the blood
• Hot flushes and sweats
• Difficulty falling asleep
• Changes in urine colour – this won't harm you
• Changes in nail colour

Fewer than 1 in 100 people have these.

• Seizures (fits) – these are very rare, affecting fewer than 1 in 100 people (1%)
• Changes to how the heart works – if you have a heart problem you may not be able to have sunitinib
• Blood clots in the brain – let your doctor now if you suddenly feel unwell, dizzy or confused
• Damage to the jaw bone (osteonecrosis) – a few people taking sunitinib have this side effect. Most of the people who have had it were also having or had recently stopped having a bisphosphonate. Have a dental check up before you start treatment and tell your dentist that you are having sunitinib. It is important to clean your teeth regularly.
• Pain in the tummy (abdomen) caused by inflammation of the pancreas, liver or gallbladder
• A hole in the bowel wall caused by the tumour shrinking – let your doctor or nurse know straight away if you have sudden tummy (abdominal) pain
• Changes in the brain causing headaches, confusion, fits (seizures), and loss of eyesight – let your doctor or nurse know straight away if you have these
• An abnormal join between 2 body cavities or from a body cavity on to the skin (fistula)

The side effects above may be mild or more severe. A side effect may get worse through your course of treatment, or more side effects may develop as the course goes on. This depends on

• How many times you've had the drug before
• Your general health
• The amount of the drug you have (the dose)
• Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so they can help you manage them. They can give you advice or reassure you. Your nurse will give you a contact number to ring if you have any questions or problems. If in doubt, call them.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and over the counter remedies – some drugs can react together. It is especially important to tell your doctor if you are taking a blood thinning drug called warfarin because it can react with the sunitinib.

The following drugs may change the level of sunitinib in your body

• Some antibiotics and anti fungal medicines
• Some HIV drugs
• Some steroids
• Some anti epileptic drugs
• Some herbal medicines such as St John's wort

Sunitinib can also react with grapefruit juice so avoid this while you are having treatment.

Sunitinib can slow wound healing so if you need to have an operation your doctor will normally advise you to stop taking it for a while beforehand. They will let you know when you can start taking it again.

Sunitinib may harm a baby developing in the womb. Talk to your doctor about contraception before having this treatment, if there is any chance you or your partner could become pregnant.

You should not breastfeed while having this drug as it may come through in the breast milk.

You should not have immunisations with live vaccines while you are having this treatment or for at least 6 months afterwards. In the UK, live vaccines include rubella, mumps, measles (usually given together as MMR), BCG and yellow fever. You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered.

It is safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with oral vaccines, but not many people in the UK have oral vaccines now. So there is usually no problem in being with any baby or child who has recently had any vaccination in the UK. You might need to make sure that you aren't in contact with anyone who has had oral polio, cholera or typhoid vaccination recently, particularly if you live abroad.

This page does not list all the very rare side effects of this treatment that are very unlikely to affect you. For further information look at the Electronic Medicines Compendium website at www.medicines.org.uk.

If you have a side effect not mentioned here that you think may be due to this treatment you can report it to the Medicines Health and Regulatory Authority (MHRA) at www.mhra.gov.uk.