A targeted cancer tablet
Osimertinib
A newer targeted cancer tablet for EGFR-mutated lung cancer, generally well tolerated but monitored for heart and lung effects.
What is Osimertinib?
Osimertinib is a newer targeted cancer tablet that blocks a signal called EGFR. It is used for non-small-cell lung cancer with an EGFR mutation, including some cases that have changed after earlier treatment. It is started and monitored by a cancer specialist but taken once a day at home. It is often better tolerated than older EGFR tablets, but the team watches for effects on the heart, such as rhythm changes (QT) and the heart's pumping, and for rare lung inflammation. It has several drug interactions and pregnancy must be avoided.
Education and reference only. This is a plain-language guide to Osimertinib — 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
Osimertinib is a newer targeted cancer therapy in the EGFR inhibitor group. EGFR is a growth signal on some cancer cells, and in certain lung cancers a gene change keeps it switched on; osimertinib is designed to block this, including a particular change that can develop after earlier EGFR treatments. It is used for EGFR-mutated non-small-cell lung cancer. It is a tablet taken once a day at home, started and supervised by an oncology team.
How it works
In EGFR-mutated lung cancer, the EGFR signal is permanently active, driving the cancer to grow. Osimertinib blocks this signal, slowing or stopping the cancer's growth, and it is designed to work even against a common change that lets earlier EGFR tablets stop being effective. It is taken continuously, and the team uses scans to monitor the response and checks the heart and lungs for less common effects.
Company & origin
Originated / developed by: AstraZeneca.
A newer targeted cancer tablet used in the UK for non-small-cell lung cancer with an EGFR mutation.
Practical use
How to take Osimertinib
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it once a day, with or without food, at around the same time each day, exactly as prescribed.
- Do not change or stop it on your own, even if you feel well, without telling your team.
- Avoid grapefruit and grapefruit juice, which can affect the level of the medicine.
- Check with your cancer team or pharmacist before starting any new medicine or supplement, as some interact or affect the heart.
- Report new breathlessness, cough, swelling, palpitations, fainting or signs of infection promptly.
Weighing it up
Advantages & disadvantages of Osimertinib
Advantages
- A newer targeted tablet that is often better tolerated than older EGFR treatments.
- Can work against a change that makes some earlier EGFR tablets stop being effective.
- Taken at home once a day, while overseen by a cancer team.
Disadvantages
- Can affect the heart, including its rhythm (QT) and pumping, needing monitoring.
- Rarely can cause inflammation of the lungs, which can be serious.
- Has several drug interactions and grapefruit is best avoided.
Practical use
Good to know
Osimertinib is generally better tolerated than older EGFR tablets, but there are a few things the team keeps an eye on. It can affect the heart, including the electrical rhythm (QT prolongation) and how well the heart pumps, so you may have ECGs and heart scans; tell your team about breathlessness, swelling, palpitations or fainting. A rare but important risk is inflammation of the lungs, so report new or worsening breathlessness or cough. Common milder effects include rash, dry skin, diarrhoea and nail changes. It has several drug interactions and grapefruit is best avoided. Do not stop it without advice, and avoid pregnancy.
Who should not take it / use with caution
- It must not be used in pregnancy, and effective contraception is needed because it can harm an unborn baby.
- It is used with caution, and extra monitoring, in people with heart problems or existing lung disease.
- People taking other medicines that affect the heart rhythm may need those reviewed or managed carefully.
Monitoring
- Regular reviews and scans to check how the cancer is responding.
- Heart tracings (ECGs) and scans of the heart's pumping, as it can affect the heart.
- Watching for breathlessness that could mean lung inflammation, and blood tests as needed.
Side effects
- Rash, dry skin, diarrhoea, mouth soreness, nail changes and tiredness are common but often manageable.
- Heart effects such as rhythm changes (QT) or reduced pumping, which are monitored.
- Less commonly, lung inflammation (report breathlessness), low blood counts or eye problems that need prompt review.
Key interactions
- Processed by the same liver enzyme as many medicines, so some antibiotics, antifungals and epilepsy drugs can change its level.
- Grapefruit can affect its level and is best avoided.
- Combining it with other medicines that affect the heart rhythm can increase the risk of rhythm problems.
Available as: Tablets taken by mouth.
Answers
Osimertinib: frequently asked questions
Is osimertinib easier to tolerate than older EGFR tablets?
It is generally better tolerated, with milder skin and gut effects for many people, though the team still monitors for heart and rare lung effects.
Why are my heart and ECG being checked?
Osimertinib can affect the heart's electrical rhythm (QT) and how well it pumps, so ECGs and heart scans help keep this safe; report breathlessness, swelling, palpitations or fainting.
What should I do if I get breathless?
New or worsening breathlessness or cough can rarely be a sign of lung inflammation, so report these to your team straight away.
Can I take it with food?
Yes, osimertinib can be taken with or without food, at around the same time each day, as your team advises.
Can I stop it if I feel well?
No. Even when you feel well, stopping on your own can let the cancer grow again, so any change must be decided with your specialist team.
Authoritative sources
- BNF
- NICE CKS
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