An anti-PD-1 immunotherapy for certain cancers
Retifanlimab
An immunotherapy given into a vein for certain cancers, helping the immune system recognise and attack cancer cells.
What is Retifanlimab?
Retifanlimab is a specialist immunotherapy used to treat certain cancers. It is a checkpoint inhibitor that blocks a 'brake' on the immune system called PD-1, helping the body's immune cells recognise and attack the cancer. It is given as a drip into a vein at regular intervals. Because it takes the brakes off the immune system, it can cause immune-related side effects that affect almost any organ, and it can also cause reactions during the infusion. These need to be reported and treated early, under specialist supervision.
Education and reference only. This is a plain-language guide to Retifanlimab — 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
Retifanlimab is an immunotherapy medicine used to treat certain cancers. It is a type of checkpoint inhibitor that blocks PD-1, one of the natural 'brakes' that normally stop the immune system being overactive. Cancers can use this brake to hide from the immune system, so by blocking PD-1, retifanlimab helps the body's immune cells find and attack the cancer. It is given as an infusion into a vein at regular intervals, under the care of a specialist cancer team.
How it works
The immune system has 'brakes', called checkpoints, that normally stop it attacking the body's own tissues; some cancers switch on a checkpoint called PD-1 to avoid being attacked. Retifanlimab blocks PD-1, releasing this brake so the immune system's T cells can recognise and destroy cancer cells more effectively. The flip side of releasing the brake is that the immune system can also turn on healthy organs, which is why immune-related side effects are the main concern. It is given at regular intervals as an infusion, with monitoring between doses.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist immunotherapy used in the UK to treat certain cancers, given as a drip into a vein.
Practical use
How to take Retifanlimab
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as a drip into a vein by your cancer team, at regular intervals.
- Report any new or worsening symptoms promptly, even if they seem minor or unrelated, as they may be immune-related.
- Tell your team straight away about chills, fever, flushing or breathlessness during or soon after the infusion.
- Do not start steroids or other treatments for side effects yourself; let your specialist team guide this.
- Use effective contraception as advised, because this medicine can harm a developing baby.
Weighing it up
Advantages & disadvantages of Retifanlimab
Advantages
- Helps the immune system recognise and attack certain cancers by releasing the PD-1 brake.
- Given as an infusion at regular intervals rather than daily tablets.
- Offers a treatment option that works through the body's own immune system.
Disadvantages
- Can cause immune-related side effects that affect almost any organ in the body.
- Can cause reactions during the infusion, such as chills, fever or breathlessness.
- Side effects can come on during or after treatment and can occasionally be severe.
Practical use
Good to know
The most important things to understand are immune-related side effects and infusion reactions. Because retifanlimab takes a brake off the immune system, it can attack healthy organs, and this can affect almost any part of the body: common examples include the bowel (diarrhoea, tummy pain, blood in the stool), the skin (rash, itching), the liver, the lungs (cough, breathlessness), and hormone glands such as the thyroid, adrenal and pituitary, which can cause tiredness, weight change or feeling unwell. These reactions can appear during treatment or even after it has finished, and can occasionally be severe, so report any new or worsening symptom promptly; treatment often involves steroids. Reactions can also happen during the infusion itself, such as chills, fever, flushing or breathlessness, so you are watched while it is given. As with cancer treatment of this kind, it can harm a developing baby, so effective contraception is important.
Who should not take it / use with caution
- People who have had a serious allergic reaction to retifanlimab should not receive it.
- It is used with caution in people with active autoimmune conditions, as the immune system may be stirred up further.
- It can harm a developing baby, so it is avoided in pregnancy and effective contraception is needed.
Monitoring
- Regular blood tests, including liver, kidney and hormone-gland checks.
- Watching for immune-related side effects affecting the bowel, skin, lungs, liver and glands.
- Observing for infusion reactions while the medicine is given.
Side effects
- Immune-related inflammation of the bowel (diarrhoea), skin (rash, itching), liver or lungs.
- Effects on hormone glands such as the thyroid, adrenal or pituitary, causing tiredness or feeling unwell.
- Infusion reactions such as chills, fever, flushing or breathlessness.
- Rarely but seriously, severe immune reactions affecting any organ, which need urgent treatment.
Key interactions
- Medicines that dampen the immune system, such as steroids, may affect how well it works, so tell your team.
- It has few routine medicine interactions, but a full medicines list is still important.
- Live vaccines are generally avoided during treatment.
Available as: A solution given as a drip into a vein.
Answers
Retifanlimab: frequently asked questions
What is retifanlimab used for?
It is an immunotherapy used to treat certain cancers, helping the immune system recognise and attack the cancer by blocking a brake called PD-1.
How does it work?
It blocks PD-1, one of the natural 'brakes' on the immune system that some cancers use to hide, so the immune system can attack the cancer more effectively.
What are immune-related side effects?
Because the brake is released, the immune system can attack healthy organs such as the bowel, skin, liver, lungs and hormone glands, so any new symptom should be reported.
Can it cause a reaction during the drip?
Yes. Infusion reactions such as chills, fever, flushing or breathlessness can occur, so you are watched while it is given; tell your team if you feel unwell.
Can side effects appear after treatment ends?
Yes. Immune-related side effects can come on during treatment or even after it has finished, so keep reporting new or worsening symptoms to your team.
Authoritative sources
- BNF
- NICE CKS
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