An infusion to reduce sickle cell pain crises
Crizanlizumab
A medicine given as a drip into a vein to reduce how often painful sickle cell crises happen.
What is Crizanlizumab?
Crizanlizumab is a specialist medicine used to reduce how often people with sickle cell disease have painful crises, also called vaso-occlusive crises. It is a monoclonal antibody that blocks a sticky molecule called P-selectin, which helps stop blood cells clumping together and blocking small blood vessels. It is given as a drip (infusion) into a vein on a regular schedule, not as a one-off treatment. The most important thing to watch for is an infusion reaction, which is why it is given slowly with monitoring. It reduces crises but does not cure sickle cell disease, and pain crises can still happen.
Education and reference only. This is a plain-language guide to Crizanlizumab — 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
Crizanlizumab is a monoclonal antibody, a type of medicine made to target one specific molecule in the body. It is used in sickle cell disease, an inherited condition in which red blood cells become stiff and sickle-shaped and can block small blood vessels, causing sudden episodes of severe pain known as crises. Crizanlizumab is given to reduce how often these crises happen in people who keep having them. It is given as a drip into a vein on a regular schedule by a specialist team, alongside the person's other sickle cell care.
How it works
In sickle cell disease, painful crises happen when blood cells stick to each other and to the lining of blood vessels and block the flow of blood. A sticky molecule called P-selectin plays a key part in this clumping. Crizanlizumab attaches to P-selectin and blocks it, making the cells less likely to stick together and clog small vessels. By dampening down this process, it lowers how often painful crises occur over time. Because it works steadily in the background, it is given regularly rather than only when a crisis happens, and it does not treat a crisis that is already underway.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist medicine used in the UK to reduce how often painful sickle cell crises happen, given as a drip into a vein.
Practical use
How to take Crizanlizumab
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Attend your appointments to receive it as a drip into a vein on the regular schedule your specialist team sets.
- Tell the staff straight away during or after the infusion if you feel unwell, such as fever, chills, flushing, breathing trouble or pain.
- Keep using your usual plan for treating a pain crisis, as this medicine prevents crises rather than treating one in progress.
- Continue your other sickle cell treatments and care, as crizanlizumab is used alongside them.
- Tell your team about any other medicines and any reactions you have had to infusions in the past.
Weighing it up
Advantages & disadvantages of Crizanlizumab
Advantages
- Can reduce how often painful sickle cell crises happen in people who keep having them.
- Targets the sticking process that drives crises, offering a different approach to other sickle cell treatments.
- Given on a regular schedule and used alongside the person's existing sickle cell care.
Disadvantages
- Given as a drip into a vein, which means regular hospital or clinic visits.
- Can cause infusion reactions, sometimes serious, so it must be given with monitoring.
- Reduces crises but does not cure sickle cell disease, so crises can still happen.
Practical use
Good to know
The key point is that crizanlizumab is given to prevent crises over time, not to treat a crisis that is already happening, so people still need their usual plan for managing pain when a crisis does occur. It is given as a slow drip into a vein, and the most important thing the team watches for is an infusion reaction, where someone feels unwell during or soon after the drip, with symptoms such as fever, chills, flushing, breathing difficulty or pain. This is why the first infusions in particular are given slowly with close monitoring and why you should tell staff straight away if you feel unwell. It reduces how often crises happen but does not cure sickle cell disease, so crises can still occur. It is used alongside, not instead of, the rest of your sickle cell care, and the team will review how well it is helping.
Who should not take it / use with caution
- People who have had a serious allergic or infusion reaction to crizanlizumab should not receive it.
- It is used with care, and under specialist guidance, in pregnancy, where benefits and risks are weighed.
- It should only be used under a specialist sickle cell service that can monitor for infusion reactions.
Monitoring
- Watching closely for infusion reactions during and after each drip.
- Reviewing how often crises happen to judge how well it is working.
- Keeping an eye on overall sickle cell care and other blood tests as needed.
Side effects
- Infusion reactions during or soon after the drip, such as fever, chills, flushing, breathing trouble or pain.
- Joint pain, back pain, nausea or headache in some people.
- Rarely, more serious infusion reactions, which is why infusions are given slowly with monitoring.
Key interactions
- It can affect some laboratory blood tests that measure platelets, so labs should know you are receiving it.
- There are few well-established routine medicine interactions, but tell your team about everything you take.
- It is used alongside, not instead of, your other sickle cell treatments.
Available as: A solution given as a drip (infusion) into a vein.
Answers
Crizanlizumab: frequently asked questions
What is crizanlizumab used for?
It is used to reduce how often people with sickle cell disease have painful crises, by blocking a sticky molecule that helps blood cells clump and block small blood vessels.
Does it treat a crisis that is happening?
No. It is given on a regular schedule to prevent crises over time; you still need your usual plan to treat a pain crisis when one happens.
How is it given?
It is given as a slow drip (infusion) into a vein at your specialist clinic, on a regular schedule the team sets.
What is an infusion reaction?
It is feeling unwell during or soon after the drip, with symptoms such as fever, chills, flushing, breathing trouble or pain; tell staff straight away if it happens.
Will I still get crises?
It reduces how often crises happen but does not cure sickle cell disease, so crises can still occur and you should keep up the rest of your care.
Authoritative sources
- BNF
- NICE CKS
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