Rasburicase

(raz-byur-ih-kase)

Trade/other name(s): Elitek

Why would this drug be used?

Rasburicase is part of a group of drugs known as cytoprotective (cell-protecting) agents. It is used to lower blood levels of uric acid, in children and adults who are getting chemotherapy that is likely to kill a large number of cancer cells in a short amount of time. This helps prevent kidney damage.

How does this drug work?

The goal of chemotherapy is to kill cancer cells. But in some cases, killing very large numbers of cancer cells in a short amount of time can actually be dangerous. As the cells die, they break open and spill their contents into the bloodstream. Some of these substances can cause serious kidney damage and other problems, a condition known as tumor lysis syndrome. One substance, uric acid, is hard for the body to get rid of quickly and can form harmful crystals in the kidneys.

Rasburicase is a manmade version of a protein (urate oxidase) that converts uric acid into another chemical called allantoin, which can be removed more easily from the body by the kidneys.

Before taking this medicine

Tell your doctor…

• If you are allergic to any medicines, dyes, additives, or foods.
• If you have been diagnosed with glucose-6-phosphate dehydrogenase (G6PD) deficiency or are of African or Mediterranean ancestry (which makes you more likely to be G6PD deficient). This drug can cause the destruction of red blood cells (hemolysis) in people with this condition.
• If you have any other medical conditions such as kidney disease, liver disease (including hepatitis), heart disease, congestive heart failure, lung disease, diabetes, gout, or infections. You may need closer monitoring of these conditions while being treated.
• If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. It is not known if this drug might cause problems if either the male or female is taking it at the time of conception or during pregnancy. Men and women who are taking this drug should use some kind of birth control during treatment. It is important to check with your doctor about what kinds of birth control can be used with this medicine. This drug should be used during pregnancy only if the potential benefit is thought to justify the potential risk to the fetus.
• If you are breast-feeding. While no studies are available at this time, this drug may pass into breast milk and affect the baby. Talk with your doctor about the possible risks of breast-feeding while taking this drug.
• About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick

Interactions with other drugs

No serious interactions with other drugs are known at this time. But this does not necessarily mean that none exist. Check with your doctor, nurse, or pharmacist about all of your medicines, herbs, and supplements, and whether alcohol can cause problems with this medicine.

Interactions with foods

No serious interactions with food are known at this time. Check with your doctor, nurse, or pharmacist about whether some foods may be a problem.

Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.

How is this drug taken or given?

Rasburicase is given as an injection into a vein (intravenous, or IV) over 30 minutes. It may be given in a hospital or doctor’s office. It is given daily for 5 days, with the first dose being given 4 to 24 hours before the start of chemotherapy. The actual dose depends on your weight.

Precautions

Patients who get this drug should also have other measures intended to reduce the risk of tumor lysis syndrome, such as intravenous (IV) fluids for hydration.

If you are have African or Mediterranean ancestors, you are more likely to have glucose-6-phosphate dehydrogenase (G6PD) deficiency. This means you may be at higher risk of hemolysis (destruction of red blood cells) if given this drug. Talk to your doctor about whether you should be tested for this condition before you start treatment. People with hemolysis can have dark colored urine, be tired, pale, short of breath, and have other symptoms of anemia. Tell your doctor if you notice any of these symptoms after you've gotten this drug.

Rarely, a person will have symptoms of low oxygen in the blood, like trouble breathing; blueness of skin, nail beds, and mouth; anxiety; drowsiness; confusion; and sometimes even loss of consciousness. This problem, called methemoglobinemia, usually starts during or soon after the drug is given. Tell your doctor or nurse right away if you notice any of these symptoms.

In rare cases, this drug can cause allergic reactions when the drug is given. Mild reactions may consist of fever, chills, skin itching, or feeling flushed. More serious reactions are rare, but can be dangerous. Symptoms can include feeling lightheaded or dizzy (due to low blood pressure), chest pain or tightness, shortness of breath, itching, hives (skin welts), back pain, or swelling of the face, tongue, or throat. Tell your doctor or nurse right away if you notice any of these symptoms during or after being given the drug.

Possible side effects

You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.

Common

• headache
• fever
• nausea/vomiting

Less common

• abdominal pain
• constipation
• diarrhea
• mouth sores
• skin rash

Rare

• allergic reaction (may include dizziness, shortness of breath, chest pain or tightness, swelling in the mouth or throat, hives, itching, flushing, or fever)*
• destruction of red blood cells (hemolysis), causing anemia*
• low white blood cell count, with increased risk of infection
• low oxygen in the blood (due to methemoglobinemia)*

*See the "Precautions" section for more detailed information.

Other side effects not listed above can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.

FDA approval

Yes – first approved in 2002

Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.