Part of the triple cystic fibrosis combination Kaftrio
Elexacaftor
Part of the triple combination Kaftrio (with tezacaftor and ivacaftor), a major advance for F508del cystic fibrosis.
What is Elexacaftor?
Elexacaftor is a cystic fibrosis medicine used as part of a triple combination called Kaftrio, alongside tezacaftor and ivacaftor. It is a major advance for people with at least one copy of the common F508del gene change, decided by a genetic test. It can affect the liver, so blood tests are done, and some people notice mood or mental-health changes that should be reported. It is taken with fatty food and interacts with several other medicines. It is a specialist medicine started and overseen by a cystic fibrosis team.
Education and reference only. This is a plain-language guide to Elexacaftor — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Elexacaftor is a CFTR modulator used to treat cystic fibrosis, a lifelong inherited condition causing thick, sticky mucus because of a faulty protein called CFTR. It is one of three medicines in the triple combination Kaftrio, working with tezacaftor (another corrector) and ivacaftor (a potentiator). This combination has been a major step forward for people who have at least one copy of the F508del gene change. It is taken by mouth with fatty food and is started by a specialist cystic fibrosis team.
How it works
The CFTR protein controls the flow of salt and water across cell surfaces, and in cystic fibrosis it does not work properly. In Kaftrio, elexacaftor and tezacaftor act as correctors, helping more of the faulty protein fold properly and reach the cell surface, while ivacaftor acts as a potentiator, helping that protein open and let salt and water move. By combining two correctors with a potentiator, the triple therapy works for more people and more effectively than earlier combinations, often greatly improving lung function and reducing flare-ups in those with a suitable gene change.
Company & origin
Originated / developed by: Vertex Pharmaceuticals.
A cystic fibrosis medicine used in the UK as part of the triple combination Kaftrio for people with at least one F508del gene change.
Practical use
How to take Elexacaftor
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take the morning dose (the combined tablets) with food that contains fat, and the separate evening ivacaftor dose with fatty food too, as directed.
- Use a meal or snack with fat, such as butter, cheese, eggs, full-fat milk or nuts, to help your body absorb it.
- Avoid grapefruit and grapefruit juice, and do not take St John's wort.
- Tell your cystic fibrosis team promptly if you notice changes in mood, anxiety, sleep or how you feel in yourself.
- Check with your team or pharmacist before starting any new medicine, supplement or herbal product.
- Continue your other cystic fibrosis treatments, such as physiotherapy and inhaled medicines, alongside it.
Weighing it up
Advantages & disadvantages of Elexacaftor
Advantages
- A major advance that works for more people with cystic fibrosis than earlier combinations, including those with one F508del change.
- Can substantially improve lung function, weight and quality of life and reduce flare-ups in those it suits.
- Taken by mouth as part of a once- and twice-daily routine that fits alongside other treatments.
Disadvantages
- Only suitable for people with at least one F508del gene change, confirmed by genetic testing.
- Can affect the liver and has been linked to mood and mental-health changes that need watching.
- Interacts with several medicines, grapefruit and St John's wort, so combinations must be checked.
Practical use
Good to know
Elexacaftor, as part of Kaftrio, has been a major advance for cystic fibrosis, but it is still gene-change-specific, so a genetic test decides whether it is right for you (it suits people with at least one F508del change). It is taken with fatty food to help absorption. The liver can be affected, so blood tests are done before and during treatment. Importantly, changes in mood and mental health — including low mood, anxiety, sleep problems or, rarely, thoughts of self-harm — have been reported, so tell your team promptly if you notice any change in how you feel. It interacts with several medicines, and you should avoid grapefruit and St John's wort. It is supervised by a specialist team and does not replace the rest of your cystic fibrosis care.
Who should not take it / use with caution
- People whose cystic fibrosis is not caused by a gene change the triple combination can act on.
- Anyone who has had a serious allergic reaction to elexacaftor, tezacaftor or ivacaftor.
- It is used with extra care and closer monitoring in people with significant liver problems or a history of mental-health difficulties, under specialist guidance.
Monitoring
- Liver blood tests before starting and regularly during treatment.
- Asking about mood and mental-health changes at reviews, and acting promptly if they occur.
- Reviewing lung function, weight and flare-ups with the cystic fibrosis team.
- Eye (cataract) checks in children and young people, as it contains ivacaftor.
Side effects
- Headache, dizziness, tummy pain, diarrhoea and a blocked or runny nose are among the more common effects.
- Changes in mood or mental health, such as low mood, anxiety or sleep problems, which should be reported.
- Changes in liver blood tests and, occasionally, rash, which is why monitoring is done.
Key interactions
- Medicines and foods that affect the liver enzymes that break it down (such as some antibiotics, antifungals, grapefruit and St John's wort) can change its levels.
- It can affect the levels of some other medicines, so your team may adjust treatment.
- Tell your cystic fibrosis team and pharmacist about all medicines, supplements and herbal products you take.
Available as: Tablets (with tezacaftor and ivacaftor) taken by mouth with fatty food.
Answers
Elexacaftor: frequently asked questions
What is Kaftrio?
Kaftrio is the triple combination of elexacaftor, tezacaftor and ivacaftor, a major advance for people with at least one copy of the F508del gene change.
Who can take it?
It is for people with at least one F508del gene change, confirmed by a genetic test, and is started by a specialist cystic fibrosis team.
Could it affect my mood?
Some people notice changes in mood, anxiety or sleep; tell your team promptly if you notice any change in how you feel, including any thoughts of self-harm.
Why take it with fatty food?
Fat helps your body absorb the medicine, so it should be taken with a meal or snack containing fat.
Does it cure cystic fibrosis?
No, it does not cure cystic fibrosis, but it can greatly improve symptoms; you should keep up your usual care, such as physiotherapy and inhaled medicines.
Authoritative sources
- BNF
- NICE CKS
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