Rasburicase in Patients at High Risk for Tumor Lysis Syndrome (TLS) During Cycle-2

Study Drugs:

Rasburicase is designed to help decrease or prevent the high level of uric acid that may
occur during the beginning of chemotherapy. A high level of uric acid results from TLS and
can lead to kidney failure.

Allopurinol is designed to help block uric acid. It is the standard of care for helping to
control increased uric acid levels caused by TLS.

Study Groups and Drug Administration:

Each cycle will last about 3 weeks.

If you are found to be eligible to take part in this study, you will receive rasburicase by
vein over about 30 minutes on Day 1 of Cycle 1 (about 4 hours before you begin receiving
chemotherapy). If the doctor thinks it is needed, you may also receive the drug on Days 2-5
of Cycle 1.

For Cycle 2, you will be randomly assigned (as in the flip of a coin) to 1 of 2 study groups.
There is an equal chance of being assigned to either group:

- If you are in Group A, you will receive rasburicase on Day 1 of Cycle 2. If the doctor
thinks it is needed, you may also receive the drug on Days 2-5 of Cycle 2.

- If you are in Group B, you will receive allopurinol by vein over 30 minutes each day on
Days 1-5 of Cycle 2.

Group B Participants: If your uric acid blood levels continue to increase in Cycle 2 and you
show symptoms of tumor lysis syndrome, you may receive rasburicase as a single dose. If the
doctor thinks it is needed, you may also receive 1 or more additional dose(s).

Study Visits:

On Day 1 of Cycle 1:

- Blood (about 1 teaspoon) will be drawn to check uric acid levels before and 4 hours
after you receive rasburicase.

- Blood (about 2 tablespoons) will be drawn for routine tests.

- Blood (about 1 teaspoon) will be drawn for antibody testing. Antibodies are proteins
made by the body that the immune system uses to help prevent disease.

On Days 2-5 of Cycle 1:

- Blood (about 1 teaspoon) will be drawn to check uric acid levels.

- Blood (about 2 tablespoon) will be drawn for routine tests.

At the end of both cycles, blood (about 1 teaspoon) will be drawn for antibody testing.

Length of Study:

You will receive drugs on this study for up to 2 cycles. You will be taken off study if
intolerable side effects occur.

Your participation in the study will be over after the follow-up visit.

Follow-Up:

Three (3) months after the end of Cycle 2, blood (about 1 teaspoon) will be drawn for
antibody testing.

This is an investigational study. Allopurinol is commercially available and FDA approved to
treat TLS. Rasburicase is commercially available and FDA approved for treating TLS for 1
cycle in patients with leukemia, lymphoma, and solid tumor cancers who are receiving
anti-cancer therapy. It is investigational to give rasburicase for 2 cycles.

Up to 55 patients will take part in this study. All will be enrolled at MD Anderson.

Inclusion Criteria:

1. Patients that are high risk for TLS or potential/intermediate risk for TLS as
described below: (a) High risk: Hyperuricemia of malignancy (Uric acid levels >7.5);
or diagnosis of very aggressive lymphoma/leukemia based on Revised European-American
Lymphoma (REAL) classification; acute myeloid leukemia, CML in blast crisis; high
grade myelodysplastic syndrome only if they have >10% bone marrow blast involvement
and given aggressive treatment similar to acute myeloid leukemia (AML). (b) Potential
risk: Diagnosis of aggressive lymphoma/leukemia based on (REAL) classification. Plus
one or more of the following criteria: lactate dehydrogenase (LDH) >/= 2 x upper limit
of normal (UNL); Stage III-IV disease; Stage I-II disease with at least 1 lymph
node/tumor > 5 cm in diameter. For patients with potential/intermediate risk for TLS-
Only those planned to receive alternating regimens (or non-standard regimens) in 2
cycles (example; R-Hyper-central venous access device (CVAD) alternating with
MTX/ARA-C) will be eligible.

2. Eastern Cooperative Oncology Group (ECOG) performance status 0-3.

3. Negative pregnancy test (females of child bearing potential) within rasburicase dose and use of efficient contraceptive method (both males and females).
Pregnancy test may be performed on serum (HCG) or urine (HCG).

4. Signed written informed consent approved by the Institutional Review Board obtained
prior to study entry.

Exclusion Criteria:

1. Prior H/O severe allergy or asthma requiring active treatment.

2. Patients with mantle cell lymphoma (MCL) with stage 1 or 2 disease.

3. Patient receiving any investigational drug for hyperuricemia within 30 days of planned
first treatment with rasburicase.

4. Pregnancy or lactation.

5. Known history of glucose-6-phosphate dehydrogenase (G6PD) deficiency.

6. Known history of hemolysis and/or methemoglobinemia.

7. Previous therapy with urate oxidase.

8. Conditions unsuitable for participation in the trial in the Investigator's opinion.

9. Unwillingness to comply with the requirements of the protocol.

10. Use of allopurinol within 72 hours of the study entry.