Temozolomide and Ascorbic Acid in Treating Patients With Recurrent High-Grade Glioma

PRIMARY OBJECTIVES:

I. To evaluate the toxicities and determine the recommended dose of intravenous ascorbic acid
given three times weekly in combination with temozolomide in patients with recurrent high
grade glioma.

SECONDARY OBJECTIVES:

I. To evaluate changes in the levels of serum ascorbic acid (using high-performance liquid
chromatography [HPLC] with coulometric electrochemical detection) during therapy with
ascorbic acid and temozolomide.

II. Radiographic assessment of disease status after 2 cycles of therapy with ascorbic acid
and temozolomide.

III. To evaluate progression-free and overall survival of patients with recurrent high grade
glioma treated with therapy with ascorbic acid and temozolomide.

IV. To descriptively examine quality of life (QOL) using European Organization for Research
and Treatment of Cancer (EORTC) Quality of Life Questionnaires (QLQ)-C30 during treatment.

OUTLINE: This is a dose-escalation study of ascorbic acid.

Patients receive ascorbic acid intravenously (IV) over 90-120 minutes three times per week
and temozolomide orally days 1-28. Treatment repeats every 4 weeks for up to 12 courses in
the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up at 30 days, every 2 months for
1 year and then periodically thereafter.

Inclusion Criteria:

- Patients must have pathologically proven diagnosis of high grade glioma

- Patients must have received prior radiation therapy and standard temozolomide

- Patients must be three or more months from the end of chemoradiotherapy or have biopsy
or imaging consistent with disease progression

- Patients must have recovered from toxicity of prior therapy

- Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 or better

- Absolute neutrophil count (ANC) count >= 1,500/mm^3

- Hemoglobin >= 8 g/dL

- Platelet count >= 100,000/mm^3

- Serum creatinine that is at or below 2.0 mg/dL

- Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) less than
1.5 times the upper limits of normal; note: if hepatic function is abnormal, the
decision to initiate temozolomide treatment should carefully consider the benefits and
risks for the individual patient

- Serum alkaline phosphatase less than 2.5 times the upper limits of normal; note: if
hepatic function is abnormal, the decision to initiate temozolomide treatment should
carefully consider the benefits and risks for the individual patient

- The patient must be aware of the neoplastic nature of his/her disease and willingly
provide written, informed consent after being informed of the procedure to be
followed, the experimental nature of the therapy, alternatives, potential benefits,
side-effects, risks, and discomforts

- Women of reproductive potential must be non-pregnant and non-nursing and must agree to
employ an effective barrier method of birth control throughout the study and for up to
6 months following treatment

- Women of child-bearing potential must have a negative pregnancy test within 7 days of
initiating study; (no childbearing potential is defined as age 55 years or older and
no menses for two years or any age with surgical removal of the uterus and/or both
ovaries)

Exclusion Criteria:

- History of uncontrollable allergic reactions to temozolomide or ascorbic acid or to
antiemetics appropriate for administration in conjunction with protocol-directed
chemotherapy

- Known human immunodeficiency virus (HIV)-positivity AND actively being treated with
highly active anti-retroviral therapy (HAART)

- History of glucose-6-phosphate dehydrogenase deficiency

- History of oxalate nephrolithiasis or urine oxalate > 60 mg/dL

- Anuria, dehydration, severe pulmonary congestion or pulmonary edema or fixed low
cardiac input since all are conditions for which osmotic diuresis are contraindicated
and ascorbic acid has high osmolarity

- Any other clinically significant medical disease or condition laboratory abnormality
or psychiatric illness that, in the Investigator's opinion, may interfere with
protocol adherence or a subject's ability to give informed consent

- Patients who are on the following drugs and cannot have a drug substitution:
flecainide, methadone, amphetamines, quinidine, and chlorpropamide; note: high dose
ascorbic acid may affect urine acidification and, as a result, may affect clearance
rates of these drugs

- Simultaneous participation in other therapeutic clinical trials will not be allowed

- Inability to co-operate with the requirements of the protocol

- Pregnant and nursing women are excluded from this study