Trial Information

Phase 2 Study of Rasburicase Administered by Two Different Schedules (Fixed Dosing vs. As Needed Dosing) in Patients at High Risk or Potential Risk for Tumor Lysis Syndrome

The Study Drug and TLS Rasburicase is designed to help decrease or prevent the high level of
uric acid that may occur during the start of chemotherapy. A high level of uric acid in the
blood may lead to decreased kidney function or kidney failure.

TLS occurs when high uric acid levels are caused by breakdown of tumor cells during the
start of chemotherapy. The dead tumor cells can release uric acid and cause other symptoms
of kidney failure, such as releasing large amounts of potassium and phosphorus (chemicals)
into the blood.

Screening Tests Before you can start treatment on this study, you will have "screening
tests." These tests will help the doctor decide if you are eligible to take part in this
study.

Your complete medical history will be recorded. You will have a physical exam, including
measurement of your vital signs (blood pressure, heart rate, temperature, and breathing
rate), height, and weight.

Blood will be drawn (about 2 tablespoons) for routine tests. Women who are able to have
children must have a negative blood (using a sample from the routine blood draw) or urine
pregnancy test.

Study Groups If you are found to be eligible to take part in this study, you will be
randomly assigned (as in the toss of a coin) to 1 of 2 groups. There is an equal chance of
being in either group.

Group A Participants in Group A will receive rasburicase by vein, over 30 minutes, on Day 1
of Cycle 1 of chemotherapy. On Days 1-7 of Cycle 1 of chemotherapy, blood (about 2
tablespoons) will be drawn for routine tests, including a check of the level of uric acid in
your blood. During Days 2-5 of Cycle 1 of chemotherapy, you will only receive rasburicase
(once a day) if the levels of uric acid are high that day.

Group B Participants in Group B will receive rasburicase by vein, over 30 minutes, once a
day from Days 1-5 of Cycle 1 of chemotherapy. On Days 1-7 of Cycle 1 of chemotherapy, blood
(about 2 tablespoons) will be drawn for routine tests, including a check of the level of
uric acid in your blood.

Both Groups Treatment with rasburicase will only be given in Cycle 1 of chemotherapy. The
chemotherapy will be given at least 4 hours (up to 24 hours) after the first dose of
rasburicase.

Length of Study When your blood test results show that you do not have antibodies to
rasburicase, your participation in this study will be over. You will be taken off this
study if the TLS gets worse or intolerable side effects occur.

This is an investigational study. Rasburicase is commercially available, but it is not FDA
approved for treating TLS. It is FDA approved for pediatric patients with leukemia,
lymphoma, and solid tumor cancers who are receiving anti-cancer therapy that is expected to
increase the blood levels of uric acid (the result of cancer cells dying from treatment).
For treating TLS in adult patients, it has been authorized for use in research only. Up to
80 evaluable patients will take part in this study. All will be enrolled at M. D. Anderson.