A pegylated asparaginase for acute lymphoblastic leukaemia
Pegaspargase
An enzyme-based chemotherapy used as part of treatment for acute lymphoblastic leukaemia.
What is Pegaspargase?
Pegaspargase is a specialist chemotherapy medicine used as part of combined treatment for acute lymphoblastic leukaemia, a cancer of the blood and bone marrow. It is an enzyme that starves leukaemia cells of a building block called asparagine, which they cannot make for themselves. It is given as an injection, often into a muscle or a vein, under cancer specialists. Important safety issues include allergic reactions (which can be severe), inflammation of the pancreas (pancreatitis), problems with blood clotting that can cause clots or bleeding, raised blood sugar and effects on the liver, so it is given with close monitoring.
Education and reference only. This is a plain-language guide to Pegaspargase — 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
Pegaspargase is a chemotherapy medicine used mainly to treat acute lymphoblastic leukaemia (ALL), a fast-growing cancer of the white blood cells. It is an enzyme called asparaginase that has been modified (pegylated) so it lasts longer in the body and is less likely to trigger allergy than older forms. It is given as part of a combination of treatments, usually as an injection into a muscle or into a vein, by a cancer specialist team. Because it works in an unusual way and has several important side effects, it is always given under close supervision with regular blood tests.
How it works
Leukaemia cells need a building block called asparagine to grow, but unlike normal cells they cannot make enough of their own and rely on getting it from the blood. Pegaspargase is an enzyme that breaks down asparagine in the blood, effectively starving the leukaemia cells of this essential supply so they cannot survive and divide. Normal cells are better able to make their own asparagine, so they are relatively less affected. The pegylated form lasts longer, so it can be given less often than older versions. It is used alongside other chemotherapy as part of a planned treatment programme.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist chemotherapy medicine used as part of treatment for acute lymphoblastic leukaemia, a cancer of the blood.
Practical use
How to take Pegaspargase
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as an injection, usually into a muscle or a vein, by your cancer team as part of a treatment plan.
- Expect to be observed after each dose, as allergic reactions can occur and can be severe.
- Report severe tummy pain, especially with sickness, straight away, as it can inflame the pancreas.
- Tell your team about leg swelling, breathlessness, a severe headache or any unusual bleeding, which can signal clotting problems.
- Attend all your blood tests, as it can raise blood sugar and affect the liver and clotting.
Weighing it up
Advantages & disadvantages of Pegaspargase
Advantages
- An important part of treatment for acute lymphoblastic leukaemia, starving the cancer cells of a key nutrient.
- The pegylated form lasts longer, so it can be given less often than older versions.
- Less likely to trigger allergy than some older forms of the enzyme.
Disadvantages
- Can cause allergic reactions, which are sometimes severe.
- Can inflame the pancreas and disturb blood clotting, leading to clots or bleeding.
- Can raise blood sugar and affect the liver, needing close monitoring.
Practical use
Good to know
Pegaspargase has several important safety issues that the team watches for closely. Allergic reactions can occur, sometimes severe, so it is given where staff can respond quickly and you are observed afterwards. It can inflame the pancreas (pancreatitis), so severe tummy pain, especially with sickness, must be reported urgently. It also affects the proteins involved in blood clotting, which can lead either to dangerous clots or to bleeding, so symptoms such as leg swelling, breathlessness, severe headache or unusual bleeding need prompt attention. It can raise blood sugar, sometimes needing treatment, and can affect the liver, so blood tests are done regularly. It can harm an unborn baby, so reliable contraception is advised. It is always given as part of specialist cancer care alongside other treatments.
Who should not take it / use with caution
- People who have had a serious allergic reaction to pegaspargase or other asparaginase medicines should not have it.
- It is avoided in people who have had pancreatitis caused by asparaginase, or with serious liver problems.
- It is used with particular care in people with a history of serious blood clots or bleeding, under specialist guidance.
Monitoring
- Observation after each dose for allergic reactions.
- Blood tests for blood sugar, liver function, clotting and blood counts.
- Watching for signs of pancreatitis, clots or bleeding, and reviewing how the leukaemia responds.
Side effects
- Allergic reactions, which can range from mild to severe.
- Inflammation of the pancreas (pancreatitis), causing severe tummy pain and sickness.
- Blood-clotting problems, leading either to clots or to bleeding.
- Raised blood sugar, liver blood-test changes, nausea, tiredness and low blood counts.
Key interactions
- Other medicines that affect blood clotting can add to the risk of clots or bleeding.
- Steroids given alongside it can add to the rise in blood sugar.
- Tell your team about all your medicines, as other cancer treatments are coordinated carefully.
Available as: A solution given as an injection into a muscle or into a vein.
Answers
Pegaspargase: frequently asked questions
What is pegaspargase used for?
It is used as part of combined treatment for acute lymphoblastic leukaemia, working by starving the leukaemia cells of a building block called asparagine.
How does it work?
It is an enzyme that breaks down asparagine in the blood; leukaemia cells cannot make enough of their own, so removing it from the blood starves them while sparing normal cells more.
What are the main risks?
Important risks include allergic reactions, inflammation of the pancreas, blood-clotting problems leading to clots or bleeding, raised blood sugar and effects on the liver, all of which are monitored.
Why am I watched after each dose?
Allergic reactions can occur and can be severe, so it is given where staff can respond quickly and you are observed afterwards.
How is it given?
It is given as an injection, usually into a muscle or a vein, by your cancer team as part of a planned treatment programme.
Authoritative sources
- BNF
- NICE CKS
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