Bimzelx (Bimekizumab)

Bimzelx (also referred to by its generic name, Bimekizumab) is a biologic medication that is used to treat severe psoriasis.

How does Bimzelx work?

Bimzelx blocks the activity of interleukin-17A (IL-17A) and interleukin 17F (IL-17F), chemical 'messengers' in the immune system which signal other cells to cause inflammation. In people with psoriasis, the immune system is overactive and creates too much inflammation, which leads to the development of psoriasis symptoms. By blocking IL-17A and IL-17F, Bimzelx aims to prevent some of that inflammation from occurring, leading to an improvement in psoriasis for some people who take it.

Who is Bimzelx for?

Bimzelx is for adults with severe psoriasis who have not had a good response from, or cannot take or tolerate other systemic treatments including ciclosporin, methotrexate or phototherapy. You will usually need to have tried these treatments before you can be offered Bimzelx. If you have tried these treatments but they did not work, Bimzelx might be an option for you

How is Bimzelx used?

Bimzelx is taken as an injection under the skin, either via a pre-filled syringe or a pre-filled pen device. The dose can vary depending on weight. Your Dermatologist, Rheumatologist or Specialist Nurse will discuss your dose with you. Most people will be trained by a nurse to administer the injection themselves. In the first 16 weeks, your prescribed dose should be taken once, every 4 weeks. After that, doses are usually taken every 8 weeks for psoriasis and every 4 weeks for PsA. Each dose for treating psoriasis is made up of 2 injections. Each dose for treating PsA is made up of 1 injection.

What are the side effects of Bimzelx?

As with all medications, some side effects are possible when taking Bimzelx. It is important to remember that not every person taking a medication will get all, or even any, of the possible side effects listed. Many side effects of Bimzelx are mild, or can be managed with other medications, and do not cause most people to stop taking it. Bimzelx is a new treatment and, as such, this side effect data comes from clinical trials, but will be updated as more ‘real-world’ experience with the treatment is collected.

The most common side effects reported include upper respiratory tract infections, headache, tiredness, thrush in the mouth or throat, fungal infections of the skin, ear infections, itchy dry skin or a rash, acne and stomach flu (gastroenteritis). If you experience these side effects, tell your Dermatologist, Rheumatologist or Specialist Nurse.

Your Dermatologist, Rheumatologist or Specialist Nurse will explain the potential side effects of Bimzelx to you and explain how to look for signs of a serious infection (these include fever, flulike symptoms, night sweats, feeling tired or short of breath, a cough that does not go away or warm, red and painful skin, or a painful skin rash with blisters). If you experience these symptoms, you should report them to your Dermatology or Rheumatology Team immediately. For a full list of potential side effects please speak to your Dermatologist, Rheumatologist or Pharmacist, or refer to the Patient Information Leaflet that comes with the Bimzelx injection.

How long will Bimzelx take to work?

Some improvement in your psoriasis may occur in the first few weeks of treatment but it can take 16 weeks to see the full benefit. If considerable improvement is not seen in 16 weeks, improvement with Bimzelx will be stopped. If this happens, your Dermatologist or Rheumatologist should discuss the next available options with you – there are a number of other biologic or systemic treatments that can be tried if Bimzelx does not work.

How safe and effective is Bimzelx?

Bimzelx is a new medication to treat moderate to severe psoriasis that was approved for use in England and Wales in September 2021 and Scotland in November 2021. ‘Real-world’ (i.e. nonclinical trial) safety and effectiveness data is being collected by a long-running study, the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR). It is recommended that all people taking biologic treatments for their psoriasis should be asked for their information to be included in this register.


The information on this page is also available in our Bimzelx (Bimekizumab) information sheet

October 2023 (Review Date: October 2026)