A tablet for long-term immune thrombocytopenia
Fostamatinib
A tablet used to treat long-term immune thrombocytopenia by reducing the immune destruction of platelets.
What is Fostamatinib?
Fostamatinib is a specialist tablet used to treat chronic immune thrombocytopenia, a condition where the immune system destroys platelets and the count stays low, raising the risk of bruising and bleeding. It is used in adults when other treatments have not worked well enough. It works by blocking a signal (an enzyme called SYK) that the immune system uses to destroy platelets, so more survive. It is taken by mouth. The main things to watch for are raised blood pressure, changes in liver blood tests, a drop in infection-fighting white cells, and diarrhoea, so it needs regular monitoring.
Education and reference only. This is a plain-language guide to Fostamatinib — 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
Fostamatinib is a medicine used to treat long-term immune thrombocytopenia in adults, a condition in which the immune system mistakenly destroys platelets, the cells that help blood clot, leaving the count low. It is used when earlier treatments have not kept the platelet count high enough. Unlike platelet-boosting medicines that prompt the marrow to make more, fostamatinib works by reducing the immune attack on platelets so more survive. It is taken by mouth as a tablet, under specialist supervision, with regular checks of blood pressure, liver blood tests and blood counts.
How it works
In immune thrombocytopenia, immune cells tag platelets and certain white cells then destroy them, partly through a signal carried by an enzyme called spleen tyrosine kinase, or SYK. Fostamatinib blocks SYK, dampening this destruction so that more platelets survive and the count can rise. Because it acts on an immune signalling pathway, it can also have effects elsewhere, which is why blood pressure, liver blood tests and white-cell counts are monitored during treatment. It is taken regularly so the effect is maintained over time.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist medicine used in the UK to treat long-term (chronic) immune thrombocytopenia in adults whose platelet counts remain low despite other treatments.
Practical use
How to take Fostamatinib
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take the tablets by mouth as prescribed, with or without food.
- Attend regular blood-pressure checks, as fostamatinib can raise blood pressure.
- Have blood tests as arranged to check your liver, blood counts and platelet response.
- Report any fever or signs of infection promptly, as the medicine can lower infection-fighting white cells.
- Tell your team about diarrhoea or other side effects, as the dose may need adjusting.
Weighing it up
Advantages & disadvantages of Fostamatinib
Advantages
- An oral tablet that works in a different way to platelet-boosting medicines, by reducing immune destruction of platelets.
- A useful option when other treatments for immune thrombocytopenia have not worked well enough.
- Can raise and maintain platelet counts in some people who have not responded to earlier treatments.
Disadvantages
- Can raise blood pressure, sometimes needing treatment.
- Can affect the liver and lower infection-fighting white cells, so needs regular blood tests.
- Diarrhoea is common, and it interacts with several other medicines.
Practical use
Good to know
Fostamatinib needs careful monitoring because of a few characteristic effects. It can raise blood pressure, sometimes enough to need treatment, so blood pressure is checked regularly and high readings are acted on. It can affect the liver, so liver blood tests are done before and during treatment. It can lower the number of neutrophils, a type of infection-fighting white cell, so blood counts are watched and any signs of infection such as fever should be reported. Diarrhoea is common and is usually manageable, but should be mentioned if troublesome. The dose may be adjusted, paused or stopped depending on how the platelet count responds and on these monitoring results, so keeping appointments matters.
Who should not take it / use with caution
- People who have had a serious allergic reaction to fostamatinib should not take it.
- It is not recommended in pregnancy, and effective contraception is advised during treatment.
- It is used with caution in people with poorly controlled blood pressure or significant liver problems, under specialist judgement.
Monitoring
- Regular blood-pressure checks, with treatment if it rises.
- Liver blood tests and full blood counts, including neutrophils, before and during treatment.
- Reviewing the platelet response to guide whether the dose is adjusted, paused or stopped.
Side effects
- Diarrhoea, nausea or other tummy upset.
- Raised blood pressure, which may need treatment.
- Changes in liver blood tests and a drop in infection-fighting white cells (neutropenia), which monitoring is designed to catch.
Key interactions
- Medicines that strongly affect liver enzymes can raise or lower fostamatinib levels, so give a full medicines list.
- It can increase the levels of certain other medicines, which may need their doses reviewed.
- It is used with care alongside other medicines that affect blood pressure or the liver.
Available as: Tablets taken by mouth.
Answers
Fostamatinib: frequently asked questions
What is fostamatinib used for?
It is used to treat long-term immune thrombocytopenia in adults when other treatments have not raised the platelet count enough.
How is it different from a platelet booster?
Rather than telling the marrow to make more platelets, it blocks an immune signal (the enzyme SYK) so fewer platelets are destroyed and more survive.
Why is my blood pressure being checked?
Fostamatinib can raise blood pressure, sometimes enough to need treatment, so it is monitored regularly and high readings are acted on.
Why do I need regular blood tests?
Blood tests check your liver and your infection-fighting white cells, both of which the medicine can affect, as well as your platelet response.
Is diarrhoea common?
Yes, diarrhoea is a common side effect; it is usually manageable, but tell your team if it is troublesome, as the dose may need adjusting.
Authoritative sources
- BNF
- NICE CKS
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