An enzyme treatment used in childhood and adult leukaemia
Asparaginase
An enzyme-based chemotherapy used as part of treatment for acute lymphoblastic leukaemia (ALL).
What is Asparaginase?
Asparaginase is a specialist chemotherapy medicine used as part of the treatment of acute lymphoblastic leukaemia (ALL), a cancer of the blood that is common in children but also affects adults. It is an enzyme that starves leukaemia cells of a nutrient they cannot make for themselves. It is given by injection, usually into a muscle or a vein, in hospital. The main risks are allergic reactions including anaphylaxis, inflammation of the pancreas, blood-clotting problems (both clots and bleeding), high blood sugar and effects on the liver, so it needs close monitoring by a specialist team.
Education and reference only. This is a plain-language guide to Asparaginase — 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
Asparaginase is a chemotherapy medicine that is actually an enzyme. It is used as part of the treatment of acute lymphoblastic leukaemia (ALL), a fast-growing cancer of certain white blood cells that is common in children but also seen in adults. It is given by injection, usually into a muscle or a vein, in hospital, as one part of a wider chemotherapy plan. There are different forms, and a particular one (sometimes called Erwinia asparaginase) is used when someone has reacted to the standard type. It is always given under close specialist supervision.
How it works
Leukaemia cells need a building block called asparagine to grow, but unlike normal cells they cannot make enough of it themselves and have to take it from the blood. Asparaginase is an enzyme that breaks down asparagine in the blood, starving the leukaemia cells of this nutrient so they cannot grow and die off. Normal cells are largely spared because they can make their own asparagine. It is given in courses as part of a combined chemotherapy plan, and its effects on clotting, the pancreas and blood sugar come from its wider action on the body's proteins.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist chemotherapy enzyme used in the UK as part of treatment for acute lymphoblastic leukaemia, given by injection.
Practical use
How to take Asparaginase
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given by injection into a muscle or a vein in hospital, as part of your chemotherapy plan.
- Stay as advised after each injection so staff can watch for allergic reactions.
- Tell staff straight away if you feel breathless, dizzy, itchy or unwell during or after an injection.
- Report severe tummy pain, swelling in a limb, breathlessness, severe headache or unusual bleeding promptly.
- Attend all blood tests, and use reliable contraception as advised during treatment.
Weighing it up
Advantages & disadvantages of Asparaginase
Advantages
- An important part of curative chemotherapy plans for acute lymphoblastic leukaemia.
- Works in a targeted way by starving leukaemia cells of a nutrient they cannot make.
- A different form is available for people who react to the standard type, so treatment can often continue.
Disadvantages
- Can cause allergic reactions, including severe whole-body reactions (anaphylaxis).
- Can cause inflammation of the pancreas, clotting problems (both clots and bleeding) and high blood sugar.
- Given by injection in hospital and needs close monitoring with regular blood tests.
Practical use
Good to know
Asparaginase needs careful watching for several serious effects. Allergic reactions are an important risk and can range from a rash to a severe whole-body reaction (anaphylaxis), which is why it is given where staff can treat reactions quickly; if someone reacts, a different form of the enzyme may be used. It can cause inflammation of the pancreas, so severe tummy pain with sickness must be reported. It affects the body's clotting proteins, which can lead both to blood clots and to bleeding, so any swelling, breathlessness, severe headache or unusual bleeding should be reported. It can raise blood sugar, sometimes a lot, and can affect the liver. As part of cancer treatment, it can harm an unborn baby, so contraception is important. It is always given as part of a specialist plan with regular blood tests.
Who should not take it / use with caution
- People who have had a serious allergic reaction to asparaginase should not have that form of it.
- It is not suitable in people with active or a history of inflammation of the pancreas.
- It is used with great caution, or avoided, in people with serious clotting or liver problems, and it can harm an unborn baby.
Monitoring
- Close watching during and after injections for allergic reactions.
- Regular blood tests including pancreas, liver, blood sugar and clotting checks.
- Watching for signs of clots, bleeding or pancreas inflammation.
Side effects
- Allergic reactions, ranging from rash and itching to severe whole-body reactions (anaphylaxis).
- Inflammation of the pancreas, causing severe tummy pain and sickness.
- Clotting problems, which can mean blood clots or, sometimes, bleeding.
- High blood sugar, effects on the liver, nausea and tiredness.
Key interactions
- Other cancer medicines given alongside it can add to effects on the liver and blood, as planned by your team.
- Medicines that affect blood clotting need careful review because asparaginase changes clotting.
- Steroids given as part of treatment can add to the rise in blood sugar.
Available as: A solution given by injection into a muscle or a vein.
Answers
Asparaginase: frequently asked questions
What is asparaginase used for?
It is a chemotherapy enzyme used as part of the treatment of acute lymphoblastic leukaemia (ALL), starving leukaemia cells of a nutrient they cannot make themselves.
Why does it cause allergic reactions?
Because it is a foreign enzyme, the body can react to it; reactions can be severe, so it is given where staff can treat them quickly, and a different form may be used if you react.
Why does it affect blood clotting?
It changes the body's clotting proteins, which can lead both to blood clots and to bleeding, so any swelling, breathlessness or unusual bleeding should be reported.
How is it given?
It is given by injection into a muscle or a vein in hospital, as one part of a wider chemotherapy plan.
Can I have it in pregnancy?
It is part of cancer treatment that can harm an unborn baby, so reliable contraception is important; discuss any pregnancy plans with your specialist.
Authoritative sources
- BNF
- NICE CKS
Building a medicines information resource?
We create evidence-led, dose-free drug and formulary references for teams.