A biologic drip for severe eosinophilic asthma
Reslizumab
A specialist add-on biologic for severe asthma driven by a type of white cell called eosinophils, given by a drip into a vein.
What is Reslizumab?
Reslizumab is a specialist biologic medicine used as an add-on treatment for severe eosinophilic asthma, a type of difficult asthma driven by raised levels of a white blood cell called the eosinophil. It is a monoclonal antibody that blocks a signal (interleukin-5) these cells need, lowering their numbers and reducing severe asthma attacks. It is given as a drip (infusion) into a vein at the hospital or clinic every few weeks, not as an inhaler. It is added on top of usual asthma inhalers rather than replacing them, and is used only when other treatments have not controlled the asthma well enough.
Education and reference only. This is a plain-language guide to Reslizumab — 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
Reslizumab is a biologic medicine, a type of treatment made from antibodies, used for people with severe asthma of a particular kind called eosinophilic asthma. In this type, a white blood cell called the eosinophil is raised and drives ongoing inflammation in the airways, leading to frequent or serious attacks. Reslizumab is an add-on treatment for adults whose asthma stays troublesome despite high-dose inhalers and other medicines. It is given by a drip into a vein at a hospital or specialist clinic, and is started and supervised by a severe-asthma specialist team after checking that eosinophils are involved.
How it works
Eosinophils need a chemical signal called interleukin-5 to grow, survive and gather in the airways, where they cause the inflammation behind eosinophilic asthma. Reslizumab is an antibody that binds to interleukin-5 and blocks it, so fewer eosinophils are produced and their numbers fall. With fewer of these cells, airway inflammation settles, which reduces severe flare-ups and can lessen the need for steroid tablets. Because it works steadily in the background, it is given on a regular schedule, and it is used alongside, not instead of, the usual inhalers that keep day-to-day asthma controlled.
Company & origin
Originated / developed by: Teva.
A specialist biologic medicine used in the UK as an add-on treatment for severe eosinophilic asthma, given by drip into a vein.
What it treats
Conditions Reslizumab is used for
Practical use
How to take Reslizumab
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as a drip into a vein at a hospital or specialist clinic on a regular schedule, so you do not take it at home.
- Keep using your usual preventer and reliever inhalers, as this is an add-on and does not replace them.
- Expect to be watched for a while after each infusion in case of a reaction.
- Allow some time to see the benefit, as it works gradually, and attend your reviews so the team can judge if it is helping.
- Tell your team straight away if your asthma gets worse or you have more attacks despite treatment.
Weighing it up
Advantages & disadvantages of Reslizumab
Advantages
- Can reduce severe asthma attacks in people with eosinophilic asthma that other treatments have not controlled.
- May lower the need for steroid tablets and their long-term effects.
- Targets the specific inflammation driving this type of asthma.
Disadvantages
- Given as a drip into a vein at a clinic every few weeks, rather than as a simple inhaler.
- Only helps the eosinophilic type of severe asthma, so it is not suitable for everyone.
- Rarely, a serious allergic reaction can occur during or after the infusion, so monitoring is needed.
Practical use
Good to know
The key point is that reslizumab is an add-on for one specific type of severe asthma, so it is only used after tests confirm raised eosinophils and after standard treatments have been optimised; it is not a general asthma medicine and does not replace your inhalers. It is given as a drip into a vein at a clinic, and you are usually watched for a while afterwards because, rarely, a serious allergic reaction can happen during or shortly after the infusion. It works gradually, so it can take a little time to see the benefit, and the team will review whether it is helping before continuing. Keep using your preventer and reliever inhalers and your asthma action plan as normal, and tell your team if your asthma worsens.
Who should not take it / use with caution
- People who have had a serious allergic reaction to reslizumab or its ingredients should not have it.
- It is not used for ordinary, well-controlled asthma or for asthma that is not the eosinophilic type.
- It is started and supervised only by a specialist severe-asthma service after appropriate testing.
Monitoring
- Watching for reactions during and after each infusion.
- Reviewing how well asthma is controlled, including attacks and steroid-tablet use, to judge benefit.
- Checking eosinophil levels and overall asthma control over time.
Side effects
- Reactions around the time of the infusion, such as flushing, breathlessness or a rash.
- Muscle aches in some people.
- Rarely, a serious allergic reaction (anaphylaxis) during or shortly after the drip, which is why you are monitored.
Key interactions
- There are few well-established routine medicine interactions, but tell your team about all your medicines.
- It is used alongside, not instead of, your usual asthma inhalers and treatments.
- Tell your team about any live vaccines you are due, as advice can differ on biologic treatments.
Available as: A solution given as a drip (infusion) into a vein at a clinic.
Answers
Reslizumab: frequently asked questions
What is reslizumab used for?
It is a specialist add-on biologic for severe eosinophilic asthma, a type driven by a raised white cell called the eosinophil, used when other treatments have not controlled the asthma.
How is it given?
It is given as a drip into a vein at a hospital or specialist clinic every few weeks, not as an inhaler or tablet.
Do I stop my inhalers?
No. Reslizumab is an add-on; you keep using your usual preventer and reliever inhalers and your asthma action plan as normal.
Why am I watched after the drip?
Rarely, a serious allergic reaction can happen during or shortly after the infusion, so the team monitors you for a while afterwards.
How will I know if it is working?
It works gradually, so the team reviews your asthma attacks and overall control over time to judge whether it is helping before continuing.
Authoritative sources
- BNF
- NICE CKS
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