Asciminib (Scemblix)

Asciminib is a type of targeted cancer drug. You pronounce it as as-sim-i-nib. It is also known as Scemblix.

It is a treatment for chronic myeloid leukaemia (CML). You might have asciminib if:

• your CML has the Philadelphia chromosome
• your CML does not have a change (mutation) in the T315I gene
• you have already had 2 or more treatments with a tyrosine kinase inhibitor (TKI)

Most people with CML have the Philadelphia chromosome.

How do you have asciminib?

You have asciminib as tablets. You swallow the tablets whole with a glass of water. You take asciminib on an empty stomach. This means taking your tablets at least 2 hours after a meal and you not eating for 1 hour after taking them.   

Speak to your pharmacist if you have problems swallowing the tablets.

Whether you have a full or an empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, no 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 have asciminib?

You may take the tablets once each day or you may take the dose split into two. So you take it in the morning and evening. Your doctor will tell you how to take it. 

You take asciminib for as long as the treatment is working, and you are not experiencing too many side effects.

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.

Before treatment starts, you have a blood test to check for the virus Hepatitis B infection. This is because infection with this virus can become active again if you’ve had it in the past. 

You also have an ECG before you start asciminib. You might have repeat ECG tests while you are having this treatment.

Side effects

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. 

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:

Increased risk of getting an infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, cough, headaches, feeling cold and shivery, pain or burning feeling when weeing, or generally feeling unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Breathlessness and looking pale

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

Bruising, bleeding gums or nosebleeds

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Infections of the sinus’ and throat (upper respiratory tract infections)

You might have an infection of your upper airways or throat. You might have a sore throat, croaky voice, stuffy or runny nose with sneezing.

Cough

You might have a cough. Talk to the team looking after you if you feel breathless.

Changes in the levels of fats in the blood

This drug can raise the amount of cholesterol and triglycerides in your blood. You will have regular blood tests to check this.

Headaches

Tell your healthcare team if you keep getting headaches. They can give you painkillers to help.

Dizziness 

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

High blood pressure

You might get 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.

Changes to how well your pancreas is working

Blood tests might show your pancreas   isn’t working very well. Asciminib can cause inflammation of the pancreas (pancreatitis), but this is less common. Tell your doctor straight away if you have sudden and severe pain in your abdomen, feeling or being sick, diarrhoea or a high temperature.

Liver changes

The changes are usually very mild and unlikely to cause symptoms. They will almost certainly go back to normal when treatment is finished. 

You have regular blood tests throughout your treatment so your doctor can check this.

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.

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 stoma , 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.

Tummy (abdominal) pain 

Tell your treatment team if you have this. They can check the cause and give you medicine to help. 

Skin rash 

Skin problems include a skin rash, dry skin and itching. This usually goes back to normal when your treatment finishes. Your healthcare team can tell you what products you can use on your skin to help.

Muscle and joint pain

You might feel some pain from your muscles and joints. This can include back and neck pain. Speak to your doctor or nurse about what painkillers you can take to help with this.

Tiredness and weakness (fatigue)

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

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:

• lung infections including pneumonia
• the flu (influenza), symptoms include a sudden fever, feeling achy and very tired
• loss of appetite
• dry eyes
• blurred vision
• a fast, racing heartbeat (palpitations)
• fluid around the lung (pleural effusion) symptoms include breathlessness and chest pain
• itchy skin with raised bumps (hives)
• high temperature
• fluid build up in your body (oedema)
• changes to how well your kidneys are working
• raised levels of an enzyme called creatine kinase (CK) in your blood and skeletal muscles. High levels can be a sign of muscle damage or inflammation, which can affect how your muscles work, including your heart muscle

Rare side effects

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

• allergic reaction – contact your healthcare team immediately if you have breathlessness, a skin rash, feel hot and flushed or swelling of the lips, mouth or throat
• changes in the way your heart works - you may have a faster heartbeat, fainting, or seizures. Call 999 or go to A&E if you have these side effects

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, food 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 while having this treatment and for at least 3 days after stopping treatment. 

Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you become pregnant while you're having treatment.

Loss of fertility 

It is not known whether this treatment affects fertility 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 at least 3 days after stopping treatment. 

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.

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 immune system 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.