Encorafenib and binimetinib

Encorafenib and binimetinib are types of targeted cancer drugs. Encorafenib is also known as Braftovi. Binimetinib is also known as Mektovi.

They are a treatment for melanoma skin cancer that either:

  • can’t be removed with surgery
  • has spread to other areas of the body (advanced or metastatic melanoma)

You can only have these drugs if you have a BRAF gene change Open a glossary item (mutation). You have tests on the melanoma cells to check for this gene change.

You pronounce encorafenib as en-ko-raf-e-nib. And binimetinib is pronounced bin-i-meh-ti-nib.

How does encorafenib and binimetinib work?

Encorafenib and binimetinib are types of cancer growth blockers. They work by targeting certain proteins that help cancer cells grow. By blocking these proteins, this combination of drugs stops or slows down the growth of cancer cells.

How you take encorafenib and binimetinib?

You take encorafenib as capsules and binimetinib as tablets.

You swallow the capsules and tablets whole with a glass of water. You can take them with or without food.

You must take tablets and capsules according to the instructions your doctor or pharmacist gives you.

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 have missed a dose.

How often do you have encorafenib and binimetinib?

You take encorafenib once a day. You take binimetinib twice a day, about 12 hours apart.

You continue taking encorafenib and binimetinib for as long as it's working or until the side effects get too bad.


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 might have other tests or scans during this treatment to check for possible side effects.

What are the side effects of encorafenib and binimetinib?

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:

  • 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 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. 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 effect

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

High temperature (fever)

If you get a high temperature, let your healthcare team know straight away. Ask them if you can take paracetamol to help lower your temperature.


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

Numbness of fingers and toes

Numbness or tingling in fingers or toes is often temporary and can improve after you finish treatment. Tell your healthcare team if you're finding it difficult to walk or complete fiddly tasks such as doing up buttons. 


Let your doctor or nurse know if you have headaches. They can give you painkillers.


This drug might make you feel dizzy. Don’t drive or operate machinery if you have this.

Eye problems

This can include blurred vision, redness, irritation, pain, loss of vision, or spots before your eyes. Some people have floaters which might appear as moving shapes, shadows or halo’s (blurred outline around objects).  

Eye problems usually get better after you stop taking these drugs.

Let your doctor or nurse know straight away if you have any eye problems.

Bleeding problems

You might bleed from different areas of the body. This includes vomiting or coughing up blood and passing blood in your wee (urine) or poo.

This can be serious. Contact your advice line if you have any bleeding.

High blood pressure

Tell your doctor or nurse if you have headaches, nosebleeds, blurred or double vision or shortness of breath. You have your blood pressure checked regularly.

Diarrhoea or constipation

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

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also 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.

Skin problems

Skin problems can include a rash, dry skin, itching, and your skin might feel thicker. Less commonly your skin might be red, look crusty, scaly or bumpy. In some cases the skin on your hands and feet may get sore, blister or peel.

Your skin might also be more sensitive to the sun and at risk of severe sunburn. It's a good idea to wear sunscreen.

Your doctor will check your skin regularly throughout your treatment.

Let your doctor, nurse or pharmacist know if you’re worried about an area of skin. They might be able to give you something to help.

Hair loss or thinning

Your hair may thin, you might lose hair in certain areas (patches) or it may go completely. It usually grows back when you finish treatment. 

Other areas of hair that might be affected include your eyelashes, eyebrows, underarm, leg and sometimes pubic hair.

Pain in different parts of your body

You might feel some pain from your tummy (abdomen), arms, legs, muscles or joints. Speak to your doctor or nurse about what painkillers you can take to help with this.

Muscle weakness and spasms

Let your doctor or nurse know if you have any weakness and spasms 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 kinase (CK). 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 or dark reddish – brown urine.

Fluid build up in your hands and legs

You may have swelling of your hands and legs due to a build up of fluid (oedema). 


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.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the levels of chemicals produced by the liver.

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:

  • another type of skin cancer called squamous cell carcinoma (SCC) or basal cell carcinoma (BCC)
  • non cancerous skin growths (skin papilloma)
  • an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness
  • taste changes
  • problems with your heart not pumping properly – you have regular tests to check this
  • blood clots - these can be life threatening. Signs are pain, swelling and redness where the clot is. Feeling breathless can be a sign of a blood clot on the lung. Contact your advice line or doctor straight away if you have any of these symptoms
  • inflammation of your bowel (colitis), symptoms include diarrhoea, pain or cramping in your tummy, pass blood in your poo (stool), and lose weight
  • changes to how well your kidneys work such as your kidneys may stop working as well. You have regular bloods tests to check this
  • tests that pick up changes in how your pancreas is working

Rare side effects

These side effects happen in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:

  • weakness or unable to move your face muscles – you may slur your words, dribble or not be able to eat or drink properly
  • inflammation of the pancreas (pancreatitis) – you might get severe tummy pain, feeling or being sick, a high temperature or you may have loose poo

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.

Loss of fertility

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


It is not known whether these drugs come through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Pregnancy and contraception

This treatment might harm a baby developing in the womb. It is important not to become pregnant or father a child while you're having treatment and for a month afterwards.

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.

If you are taking hormonal contraceptives like the pill, you should also use another barrier method such as a condom for at least a month. This is because encorafenib affects how well hormonal contraceptives work.

Treatment for 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.


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 immune system Open a glossary item 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.

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.

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