An injection for psoriasis and inflammatory spine conditions
Bimekizumab
An under-the-skin injection used for psoriasis and inflammatory spine and joint conditions that works by blocking inflammatory messengers called interleukin-17.
What is Bimekizumab?
Bimekizumab is a specialist biologic injection used for moderate to severe plaque psoriasis and for inflammatory conditions of the spine and joints, such as axial spondyloarthritis and psoriatic arthritis. It works by blocking interleukin-17, a group of immune messengers that drive these conditions. It is given as an injection under the skin. A particular feature is that it can increase fungal infections, especially oral thrush (candida), and it is used with care in people with inflammatory bowel disease. People are screened for infections, including tuberculosis, before starting, and serious infections are a recognised risk.
Education and reference only. This is a plain-language guide to Bimekizumab — 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
Bimekizumab is a type of medicine called a biologic, more specifically an interleukin-17 inhibitor, used to treat moderate to severe plaque psoriasis and inflammatory conditions affecting the spine and joints, including axial spondyloarthritis and psoriatic arthritis. It works on the immune system to reduce the inflammation that causes thick, scaly skin patches or painful, stiff joints and spine. It is given as an injection under the skin, usually after training, and is started and supervised by specialist teams who screen for infection before treatment.
How it works
Psoriasis and related inflammatory joint and spine conditions are driven in part by immune messengers called interleukin-17, which switch on inflammation in the skin and joints. Bimekizumab blocks two forms of this messenger (interleukin-17A and interleukin-17F), reducing the inflammatory signals more fully and helping the skin clear and the joints settle. Because interleukin-17 also helps the body keep fungal infections in check, blocking it explains why fungal infections, particularly oral thrush, are a recognised side effect of this medicine.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist biologic injection used in the UK for moderate to severe plaque psoriasis and for inflammatory conditions of the spine and joints, given under the skin.
Practical use
How to take Bimekizumab
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as an injection under the skin, often by yourself or a carer after training.
- Follow the schedule your specialist sets, which usually starts with closer doses and then spaces them out.
- Watch for and report signs of thrush, such as white patches in the mouth, soreness or difficulty swallowing.
- Tell your team promptly about signs of infection, or any new or worsening tummy symptoms or bloody diarrhoea.
- Do not have live vaccines without checking first, and tell health professionals that you are on a biologic.
Weighing it up
Advantages & disadvantages of Bimekizumab
Advantages
- Can clear or greatly improve moderate to severe psoriasis and ease inflammatory spine and joint conditions.
- Given as an injection under the skin at intervals rather than daily.
- Can be self-injected at home after training.
Disadvantages
- Commonly causes fungal infections such as oral thrush, by blocking interleukin-17.
- Can increase the risk of serious infections, so screening and monitoring are needed.
- Used with caution in inflammatory bowel disease, which can sometimes flare.
Practical use
Good to know
A particular thing to know about bimekizumab is that, because it blocks interleukin-17 which helps control fungal infections, it commonly causes thrush (candida), especially in the mouth and throat; this is usually treatable, but any white patches, soreness or difficulty swallowing should be reported. It can also make other infections more likely, so people are screened for infections, including tuberculosis, before starting and watched during treatment. It is used with caution in people with inflammatory bowel disease, such as Crohn's disease or ulcerative colitis, as their condition can sometimes flare, so any new or worsening tummy symptoms or bloody diarrhoea should be reported. Live vaccines are generally avoided. It is a long-term treatment given by injection under the skin, often started after a few closer-together doses and then continued at longer intervals.
Who should not take it / use with caution
- People who have had a serious allergic reaction to bimekizumab should not use it.
- It is avoided in people with a serious active infection, including tuberculosis, until this is treated.
- It is used with caution in people with inflammatory bowel disease, as their condition can flare.
- It is used in pregnancy only after specialist advice, weighing the benefits and risks.
Monitoring
- Screening for infections, including tuberculosis, before starting and checking vaccinations.
- Watching for thrush and other infections during treatment.
- Reviewing how well the skin or joints respond and checking for any bowel symptoms over time.
Side effects
- Thrush (candida), especially in the mouth and throat.
- Upper respiratory infections, such as colds and sore throats.
- Reactions where the injection is given, such as redness or soreness.
- Less commonly, more serious infections, or a flare of inflammatory bowel disease, which need prompt attention.
Key interactions
- Taking it with other medicines that weaken the immune system increases the risk of infection.
- Live vaccines are generally avoided while on treatment.
- Tell your team about all your medicines, including any treatment for bowel conditions.
Available as: A solution for injection under the skin, often given by the patient.
Answers
Bimekizumab: frequently asked questions
What is bimekizumab used for?
It is used for moderate to severe plaque psoriasis and for inflammatory conditions of the spine and joints, such as axial spondyloarthritis and psoriatic arthritis.
How does it work?
It is a biologic that blocks interleukin-17, a group of immune messengers that drive the inflammation in the skin and joints, helping the skin clear and the joints settle.
Why does it cause thrush?
Interleukin-17 helps the body keep fungal infections in check, so blocking it makes thrush (candida), especially in the mouth and throat, more likely; this is usually treatable but should be reported.
Is it safe with bowel conditions?
It is used with caution in people with inflammatory bowel disease, as the condition can sometimes flare, so report any new or worsening tummy symptoms or bloody diarrhoea.
Do I need tests before starting?
Yes. People are screened for infections, including tuberculosis, before starting, and vaccinations are checked, because the medicine can raise the risk of infection.
The wider class
About Interleukin (IL-17) biologic
Bimekizumab belongs to the interleukin (il-17) biologic class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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