Encorafenib (Braftovi®) and binimetinib (Mektovi®)

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

During a course of treatment, you will meet someone from your cancer team, such as a:

• cancer doctor
• specialist nurse
• specialist pharmacist.

This is who we mean when we mention doctor, nurse or pharmacist in this information.

During your course of treatment, you will have regular blood tests. You will also have regular heart tests such as an ECG or echocardiogram. These blood and heart tests are to check that it is safe for you to have treatment.

You will meet with a doctor, nurse or pharmacist regularly during treatment. They will talk to you about your blood results and ask how you have been feeling.

You will keep taking this treatment for as long as it is working for you and any side effects can be managed.

Your doctor, nurse or pharmacist will give you the encorafenib capsules and binimetinib tablets to take home. They may give you capsules and tablets of different strengths. Always take them exactly as they tell you to. This is important to make sure they work as well as possible for you.

Your cancer team may also give you anti-sickness drugs and other medicines to take home. Take all your capsules or tablets exactly as they tell you to.

You can take these drugs with or without food. Make sure you:

• swallow them whole with a glass of water
• do not chew, open, break or crush them
• take them at the same times every day.

If you forget to take encorafenib, you can still take your dose as long as it is not more than 12 hours late. If there is less than 12 hours until the next dose, do not take the forgotten dose. Take the next dose at the usual time.

If you forget to take binimetinib, you can still take your dose as long as it is not more than 6 hours late. If there is less than 6 hours until the next dose, do not take the forgotten dose. Take the next dose at the usual time.

Do not take a double dose of encorafenib or binimetinib to make up for a missed dose. Contact the hospital on the 24-hour number you have been given for advice.

Other things to remember about your capsules and tablets:

• Keep them in the original package and at room temperature, away from moisture, heat and direct sunlight.
• Keep them safe, where children cannot see or reach them.
• If you are sick (vomit) just after taking them, do not take an extra dose. Take your next dose at the usual time.
• Do not throw away unused capsules and tablets. Return them to your cancer team at the hospital.

You should avoid eating grapefruit and drinking grapefruit juice whilst taking encorafenib. Grapefruit can affect how the treatment works and may increase side effects.

Binimetinib tablets contain lactose. Tell your doctor if you have a lactose intolerance.

Your doctor, nurse or pharmacist will prescribe anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as they tell you to, even if you do not feel sick. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluid often and eat small amounts regularly. It is important to drink enough fluids. If you continue to feel sick, or if you are sick (vomit) 1 to 2 times in 24 hours, contact the hospital on the 24-hour number as soon as possible. They will give you advice. They may change your anti-sickness treatment. Let them know if you still feel sick.

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

Your doctor, nurse or pharmacist may give you anti-diarrhoea drugs to take at home. 

If you have diarrhoea or a mild increase in stoma activity, follow their advice about: 

• taking anti-diarrhoea drugs 
• how much and what type of fluids to drink 
• any changes to your diet that might help. 

Contact the hospital straight away on the 24-hour number if:

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

You may need to give a stool sample, or go to hospital to have fluids through a drip or antibiotics.

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. 

You may get pain in your tummy (abdomen), or have indigestion. Your doctor, nurse or pharmacist can give you advice or treatment to help. Contact the hospital straight away on the 24-hour number if your symptoms do not go away, or get worse.

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 and eyesight. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during treatment or after it ends:

• sore, painful, or swollen eyes
• eyes that are sensitive to light
• changes to your eyesight.

You may need steroids or other treatments. A specialist eye doctor (ophthalmologist) may also need to check your eyes. 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 or liver work. This is usually mild and goes back to normal after treatment ends. You will have blood tests to check how well your kidneys and liver are working. Contact the hospital on the 24-hour number if you:

• have blood in your urine (pee)
• are passing less urine or peeing less often than usual.

Drinking fluids also helps protect your kidneys. The advice is usually to try to drink at least 2 litres (3½ pints) of fluid each day. But follow any advice from your doctor, nurse or pharmacist about how much is right for you.

This treatment can cause a high temperature. Contact the hospital on the 24-hour telephone number if you feel hot, flushed or shivery. They will check what may be causing your symptoms and will give you advice.

This treatment can cause high blood pressure. You will have your blood pressure regularly checked during treatment. If needed, you will be prescribed medicines to control your blood pressure.

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 increase your risk of bleeding. Contact the hospital straight away on the 24-hour number if you have any bleeding that you cannot explain. This includes:

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

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.

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.

This treatment can make you feel dizzy. This is usually mild. Contact the hospital on the 24-hour telephone number if you feel dizzy or faint. If you feel dizzy, do not drive or use machinery.

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.

Cancer doctors usually recommend that people with cancer have vaccinations for flu and coronavirus (covid). They may also recommend other vaccines, such as Shingrix^® for shingles. These all help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

You should not have live vaccines if your immune system is weak. This includes if you are having or recently had chemotherapy, radiotherapy or other cancer treatments that affect your immune system. Live vaccines can make you unwell because they contain a very weak version of the illness they protect you against. There are several live vaccines. These include the yellow fever vaccine and Zostavax^®, which is a different type of shingles 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.