Patient Leaflet Updated 30-Jun-2025 | Pierre Fabre Limited
Nerlynx 40 mg film-coated tablets
Nerlynx 40 mg film-coated tablets
neratinib
1. What Nerlynx is and what it is used for
2. What you need to know before you take Nerlynx
3. How to take Nerlynx
4. Possible side effects
5. How to store Nerlynx
6. Contents of the pack and other information
Nerlynx contains the active substance ‘neratinib’. It belongs to a group of medicines called ‘tyrosine kinase inhibitors’ used to block cancer cells and treat breast cancer.
Nerlynx is used for patients who have early stage breast cancer which:
The ‘HER2 receptor’ is a protein found on the surface of cells in the body. It helps control how a healthy breast cell grows. In HER2-overexpressed/amplified breast cancer, the cancer cells have an increased amount of HER2 receptors on their surface. This results in the cancer cells dividing and growing faster.
‘Hormone receptors’ are also proteins expressed inside the cells of some specific tissues. Estrogens and progesterone bind to these proteins and regulate cell activity. In HR-positive breast cancer, tumor cell division and growth can be enhanced by estrogens and/or progesterone.
Before Nerlynx is used, your cancer must have been tested to show it is HR-positive and HER2-overexpressed/amplified. You must also have previously been treated with trastuzumab based therapy.
Nerlynx works by blocking the HER2 receptors on the cancer cells. This helps to stop the cells from dividing and growing.
Talk to your doctor or pharmacist before taking Nerlynx.
Nerlynx can cause diarrhoea early during treatment. It can appear more than one time. You should take an anti-diarrhoea medicine that your doctor has recommended so that your diarrhoea does not become severe, and to prevent you from getting dehydrated during treatment with Nerlynx. Dietary changes (including adapted fluid intake) and appropriate dose modifications of Nerlynx might be needed for diarrhoea management.
Nerlynx can cause changes in liver function – these are shown in blood tests. Your doctor will do blood tests before and during your treatment with Nerlynx. Your doctor will stop your treatment with Nerlynx if your liver tests show severe problems.
You should be closely monitored by your doctor if you suffer from:
If you are 65 or over you should be closely monitored by your doctor.
Do not use in children and adolescents under 18 years of age. The safety of Nerlynx and how effective it is has not been studied in this age group.
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. The efficacy and/or safety of Nerlynx and/or other medicines might be modified when taken concomitantly. This is because Nerlynx can affect the way some other medicines work. Also some other medicines can affect the way Nerlynx works.
In some cases, dose modifications or close monitoring can be done by your doctor.
In particular tell your doctor or pharmacist if you are taking any of the following medicines:
If any of the above apply to you (or you are not sure), talk to your doctor or pharmacist before taking Nerlynx.
Do not take grapefruit or pomegranate while you are taking Nerlynx – this includes eating them, drinking the juice or taking a supplement that might contain them. This is because these fruits may interact with Nerlynx and affect how the medicine works.
If you are pregnant, the doctor will assess the potential benefit to you and the risk to the foetus before giving this medicine to you. If you become pregnant while taking this medicine, the doctor will assess the potential benefit to you and the risk to the foetus, of continuing treatment with this medicine.
Women who can become pregnant must use an effective method of contraception, including a barrier method:
Men must use an effective barrier method of contraception such as a condom:
Talk to your doctor before taking Nerlynx if you are breast-feeding or plan to breast-feed because it is unknown if small amounts of this medicine may pass into your breast milk. Your doctor will discuss with you the benefits and risks of taking Nerlynx during this time.
Nerlynx has minor influence on the ability to drive and use machines. The side effects of Nerlynx (for example, dehydration and dizziness resulting from diarrhoea, fatigue, and fainting) may affect how tasks that require judgment, motor or cognitive skills are carried out.
Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.
The recommended dose of Nerlynx is 6 tablets once a day (a total of 240 mg).
The course of treatment is one year.
If you get side effects, your doctor may adjust the dose or stop treatment temporarily or permanently.
Nerlynx can cause diarrhoea early during treatment unless anti-diarrhoea medicine is taken to prevent or reduce diarrhoea. Diarrhoea usually happens early in treatment with Nerlynx and may be severe and recurrent, causing you to get dehydrated. Your doctor will tell you how to adapt your diet and fluid intake.
If you take more Nerlynx than you should, contact a doctor or a hospital straight away. Take the medicine pack with you.
Some side effects associated with taking more Nerlynx than you should are: diarrhoea, nausea, vomiting and dehydration.
If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
Like all medicines, this medicine can cause side effects, although not everybody gets them. The following side effects may happen with this medicine:
Nerlynx can cause diarrhoea (increase in number per day and/or change in stool consistency) early during treatment unless anti-diarrhoeal medicines are taken to prevent or reduce diarrhoea. The diarrhoea may be severe, and you may get dehydrated. See section 3 for more information about the anti-diarrhoea treatment you need to take at the same time as Nerlynx.
Talk to your doctor if:
Nerlynx can cause changes in liver function - these are shown in blood tests. You may or may not have signs or symptoms of liver problems (e.g., yellow skin and/or eyes, dark urine, or light-colour stools). Your doctor will do blood tests before and during your treatment with Nerlynx. Your doctor will stop your treatment with Nerlynx if your liver tests show severe problems.
Tell your doctor or pharmacist if you notice any of the following side effects:
Very common (may affect more than 1 in 10 people):
Common (may affect up to 1 in 10 people):
Uncommon (may affect up to 1 in 100 people):
Tell your doctor or pharmacist if you notice any of the side effects above.
If you get any side effects, talk to your doctor, nurse or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
By reporting side effects you can help provide more information on the safety of this medicine.
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the bottle and carton after EXP. The expiry date refers to the last day of that month.
This medicinal product does not require any special temperature storage conditions.
Keep the bottle tightly closed in order to protect from moisture.
Do not use Nerlynx if you notice any signs of damage to the packaging or if there are any signs of tampering (e.g., inner seal is broken).
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
The film-coated tablets are red oval shaped and debossed with ‘W104’ on one side and plain on the other side.
Nerlynx film-coated tablets are packaged in a white, high-density polyethylene (HDPE) round bottle with child-resistant, polypropylene closure, and foil induction inner seal for a tamper-evident seal. Each bottle contains 180 film-coated tablets.
An HDPE desiccant canister with 1 g silica gel is enclosed with the tablets in each bottle. Do not swallow the desiccant. Keep it inside the bottle.
This leaflet was last revised in 06/2025
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