Encorafenib (Braftovi®) and binimetinib (Mektovi®)

Encorafenib comes in capsules that you take once a day. Binimetinib comes in tablets that you take twice a day, 12 hours apart.

During treatment you usually see a cancer doctor, a cancer nurse or specialist nurse, and a specialist pharmacist. This is who we mean when we mention doctor, nurse or pharmacist in this information.

Before and during treatment you will have some tests, including:

• blood tests – to check the levels of blood cells and how your liver and kidneys are working
• heart tests, such as an ECG or echocardiogram – to check how your heart is working. 

At your appointments, the doctor, nurse or pharmacist will talk to you about your test results and ask you how you have been feeling. Sometimes they will change the dose or stop your treatment for a time to let your body recover from side effects.

The nurse or pharmacist will give you the capsules and tablets to take home. You may be given capsules of different strengths. Always take them exactly as explained. This is important to make sure they work as well as possible for you. 

Your nurse or pharmacist may also give you anti-sickness drugs and other medicines to take home. Take all your capsules or tablets exactly as they have been explained to you.

You can take encorafenib and binimetinib with or without food. Take them at the same times every day. Swallow them whole with a glass of water. Do not chew, break or crush them. You should avoid eating grapefruit or drinking grapefruit juice. Grapefruit may affect how encorafenib works. 

If you forget to take encorafenib: 

• you should take it when you remember – if it is more than 12 hours until your next dose
• you should wait and take the next dose at the usual time – if it is less than 12 hours until your next dose
• you should not take a double dose.

If you forget to take binimetinib: 

• you should take it when you remember – if it is more than 6 hours until your next dose
• you should wait and take the next dose at the usual time – if it is less than 6 hours until your next dose 
• you should not take a double dose.

Other things to remember about your capsules and tablets:

• Keep them in the original package.
• Keep them safe and out of sight and reach of children.
• If you are sick after taking the capsules or tablets, contact the hospital. Take the next dose at the usual time. Do not take a double dose. 

If your treatment is stopped, return any unused capsules and tablets to the pharmacist.

You may feel sick during this treatment. Your doctor will give you anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as your nurse or pharmacist tells you. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluids often and eat small amounts regularly. It is important to drink enough fluids. If you continue to feel sick, or are sick (vomit) more than once in 24 hours, contact the hospital as soon as possible. They will give you advice. Your doctor or nurse may change the anti-sickness drug to one that works better for you.

This treatment may cause severe diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.

Your hospital team may give you anti-diarrhoea drugs to take at home.

If you have diarrhoea or a mild increase in stoma activity:

• follow any advice from your cancer team about taking anti-diarrhoea drugs
• drink at least 2 litres (31/2 pints) of fluids each day.

Contact the hospital straight away if:

• you have diarrhoea at night
• you have diarrhoea more than 4 times in a day 
• you have a moderate or severe increase in stoma activity 
• the anti-diarrhoea drugs do not work within 24 hours.

You may need to go to hospital to have fluids through a drip.

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

• Drink at least 2 litres (3½ pints) of fluids each day.
• Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
• Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

This treatment can cause pain in your tummy (abdomen). Tell your doctor or nurse if this happens 

They can give you advice and treatment if needed. If you get severe pain in your tummy contact your doctor straight away.

Feeling tired is a common side effect of this treatment. It is often worse towards the end of treatment and for some weeks after it ends. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can help you feel less tired. 

If you feel sleepy, do not drive or use machinery.

This treatment can affect your eyes. Always tell your doctor or nurse if you have sore eyes, blurry vision or any sight loss. They may give you eye drops or other treatments to help. They may also arrange a specialist eye check for you. Do not drive if your eyesight is affected.

This treatment can cause pain in your muscles or joints. If this happens, tell your doctor so they can give you painkillers. Tell them if the pain does not get better. 

Sometimes this treatment can cause a muscle condition called rhabdomyolysis. Symptoms may include: 

• muscle pain
• weakness 
• dark-red or brown urine (pee).  

This condition is not common and does not always cause symptoms. You will have regular blood tests to check for signs of it. Your doctor may change the dose or stop your treatment for a time to let your body recover from this side effect.

This treatment can affect how your kidneys and liver work. This is usually mild and goes back to normal after treatment. You will have blood tests to check how well your kidneys and liver is working.

It is important to drink at least 2 litres (3½ pints) of fluids each day to help protect your kidneys

This treatment can cause high blood pressure. Your doctor or nurse will check your blood pressure regularly during treatment. If needed they will give you medicines to control your blood pressure.

This treatment may increase your risk of bleeding. Tell your doctor if you have any bruising or bleeding that you cannot explain. This includes:

• blood in your pee 
• blood in your poo, or black poo
• bleeding from the rectum (back passage)
• vomiting up blood
• vomit that looks like coffee grounds.

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may feel:

• very low in energy
• breathless 
• dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

This treatment may cause headaches. If you have headaches, tell your doctor, nurse or pharmacist. They can give you advice about painkillers that may help. Tell them if the headache does not get better, or gets worse.

This treatment may cause a rash or itchy skin. Or you may notice some areas of skin become thicker than usual. Your skin in some areas may become darker. Less commonly, the skin may peel or you may get small acne-like bumps.

Your skin may become more sensitive to light than usual. If your skin feels dry, try using an unperfumed moisturising cream every day.

These changes are usually temporary and improve after treatment finishes. Always tell your doctor or nurse straight away about any skin changes. They can check your skin and give you advice. They may arrange further tests or give you creams or medicines to help.

This treatment can affect the palms of your hands and the soles of your feet. This is called palmar-plantar or hand-foot syndrome. 

If you have white skin these areas may become red. If you have black or brown skin, these areas might get darker. 

The skin on the palms of your hands and the soles of your feet may:

• be sore
• be painful, tingle, or swell
• peel, crack or blister. 

If you have any of these symptoms, contact the hospital straight away on the 24-hour number. They can give you advice. This is especially important if you have any broken skin or if walking is difficult. They can prescribe creams and painkillers to help.

You can care for your hands and feet by: 

• keeping your hands and feet cool by washing in cool water
• gently moisturising your hands and feet regularly
• wearing gloves to protect your hands and nails when working in the house or garden
• wearing loose cotton socks and avoiding tight-fitting shoes and gloves.

Your hair may get thinner or you may lose all the hair from your head. Hair loss is almost always temporary. Your hair will usually grow back after treatment ends. Your nurse can talk to you about ways to cope with hair loss.

This treatment can cause a build-up of fluid in the body. This will slowly get better after treatment ends. Contact the hospital on the 24-hour number if you:

• are gaining weight 
• have swelling in your face, legs or ankles.

They can give you advice and treatment to help.

This treatment may affect the nerves in your fingers and toes. This can cause numbness, tingling or pain in your hands or feet. This is called peripheral neuropathy. You might find it hard to do fiddly tasks such as fastening buttons or tying shoelaces.

If you have these symptoms, always tell your doctor, nurse or pharmacist. They sometimes need to change the drug or the dose of the drug. The symptoms usually improve slowly after treatment ends. But for some people they continue and are a long-term side effect of treatment.

Some medicines can affect how this treatment works or be harmful while you are having it. Always tell your cancer doctor, nurse or pharmacist about any drugs you are taking or planning to take, such as: 

• medicines you have been prescribed
• medicines you buy in a shop, pharmacy or online
• vitamins or supplements 
• herbal drugs and complementary or homeopathic therapies
• recreational drugs – for example, cannabis.

Doctors usually recommend that people with cancer have vaccinations for flu and for coronavirus (covid). These help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

If your immune system is weak, you should not have live vaccinations. Live vaccines can make you unwell because they contain a very weak version of the illness they will protect you against. Live vaccines include Zostavax^®, which is a shingles vaccine, and the yellow fever vaccine.

It is important to ask your doctor, nurse or pharmacist for advice about having vaccinations. They can explain what vaccines are right for you and when it is best to have them.

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

• what types of contraception to use 
• how long after treatment you should continue to use contraception. 

You are advised not to breastfeed while having this treatment, or for some time after treatment ends. This is because the drugs could be passed to the baby through breast milk. 

Your doctor, nurse or pharmacist can give you more information.

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.