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Information about Oncaspar▼

What is it and what is it used for?

Oncaspar is a cancer medicine used in adults and children to treat acute lymphoblastic leukaemia (ALL), a cancer of white blood cells called lymphoblasts. Oncaspar is used in combination with other cancer medicines.

How Oncaspar works
The active substance (pegaspargase) contains the enzyme asparaginase which works by breaking up and reducing the blood levels of the amino acid asparagine. The cancer cells need this amino acid to grow and multiply, and so its reduction in the blood causes the cells to die. Normal cells, by contrast, can produce their own asparagine and are less affected by the medicine.

The asparaginase enzyme in this medicine is linked to a chemical which slows down its removal from the body and can reduce the risk of allergic reactions.

How Oncaspar is used
Oncaspar is normally given every 14 days by injection into a muscle or by infusion (drip) into a vein, with the dose depending on age and body surface area.

Oncaspar can only be obtained with a prescription and only healthcare professionals with experience of cancer treatments should prescribe and give the medicine. The healthcare professional should give the medicine in a hospital where resuscitation equipment is available.

For more information about using Oncaspar, see the patient leaflet or contact your doctor or pharmacist.

What are the benefits?

Studies showed Oncaspar to be effective in patients with ALL, including patients who were allergic to asparaginase. Oncaspar also comes with the advantage of requiring fewer injections as the medicine stays longer in the body than some other asparaginases. However, the data in adult patients were limited and the company that markets the medicine is to provide further data of its benefit in this group of patients.

As for its risks, the side effects of Oncaspar are similar to those of other asparaginase medicines and are considered manageable

The European Medicines Agency therefore decided that Oncaspar’s benefits are greater than its risks and it can be authorised for use in the EU.

The European Medicines Agency therefore concluded that the benefits of Oncaspar are greater than the risks and recommended that it be approved for use in the EU.

What are main side effects?

The most common side effects with Oncaspar (which may affect more than 1 in 10 people) include:
  • signs of liver problems (raised levels of liver enzymes and bilirubin in the blood)
  • reduced blood clotting
  • high levels of fats in the blood
  • high levels of blood glucose
  • low levels of white blood cells accompanied by fever
For the full list of side effects of Oncaspar, see the patient leaflet.

Who should avoid taking it?

Oncaspar must not be used in patients with severe liver disease, patients who have ever had pancreatitis (including pancreatitis caused by previous asparaginase treatments) or patients who have had severe bleeding or serious blood clots following asparaginase treatment.

For the full list of restrictions, see the patient leaflet.

What studies have been done?

In a study in 118 children newly diagnosed with ALL, 75% of those treated with Oncaspar (in combination with other medicines) were free of the cancer after 7 years, without having relapse or a new cancer during that period. This compares with 66% of those treated with another asparaginase.

In another study of 76 children whose cancer returned after earlier treatment, around 40% of Oncaspar-treated patients (some of whom were allergic to other asparaginase treatments) were cleared of the cancer, compared with 47% of patients treated with an asparaginase comparator.


Oncaspar was first approved for use in the EU in 2016. It is manufactured by Servier.

European Medicines Agency website page for Oncaspar (accessed 21/08/19)
Links available in External Resources

New medicines and vaccines that are under additional monitoring have an inverted black triangle symbol (▼) displayed in their package leaflet and summary of product characteristics, together with a short sentence explaining what the triangle means – it does not mean the medicine is unsafe. You should report all suspected adverse drug reactions (ADRs) for these products. ADRs can be reported by your doctor, pharmacist or online via the Yellow Card system.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions (side effects) after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals or patients are asked to report any suspected adverse reactions via the Yellow Card Scheme at or search for MHRA Yellow Card in the Google Play or Apple App Store.

Disclaimer: This site is designed to offer information for general educational purposes only. The health information furnished on this site and the interactive responses are not intended to be professional advice and are not intended to replace personal consultation with a qualified physician, pharmacist, or other healthcare professional. We cannot provide individual medical advice. You must always seek the advice of a professional for questions related to a disease, disease symptoms, and appropriate therapeutic treatments.

For the full list of side effects and restrictions, see the package leaflet (link to package leaflet available in External Resources).