Dose-Intense Temozolomide in Recurrent Glioblastoma

Inclusion Criteria: * Must provide independent consent or must demonstrate willingness to participate in the study and to adhere to dose and visit schedules. * 18 years of age or older (of either sex, and of any race) * Histologic diagnosis of GBM or gliosarcoma with an unequivocal progression by MRI or CT scan * Must have received standard combined modality therapy as first-line treatment consisting of RT plus concomitant temozolomide followed by adjuvant temozolomide (at least 2 cycles of adjuvant temozolomide) * Gadolinium MRI or contrast CT scan must be obtained within 14 days prior to registration, and must be on a steroid dose that has been stable for at least 5 days. * Karnofsky Performance status of 60 or greater * Life expectancy of at least 8 weeks * Recovered from the toxic effects of prior therapy, and 21 days must have elapsed since prior treatment with temozolomide o If a patient has residual toxicity from any previous treatment, toxicity must be ≤ Grade 1 * Laboratory tests within parameters outlined in the protocol * Female subjects of childbearing potential \& male subjects with female partner of childbearing potential must agree to use a medically accepted method of contraception or be surgically sterilized prior to Screening, while receiving protocol-specified medication, and for 30 days after stopping the study medication * Negative pregnancy test within 48 hours prior to dosing with the study drug (for female subjects of childbearing potential) * Free of any clinically relevant disease that would, in the Principal Investigator's opinion, interfere with the conduct of the study or study evaluations * Must be able to adhere to the dosing and visit schedules, and agree to record medication times, concomitant medications, and adverse events (AEs) accurately and consistently in a daily diary * Unstained slides (at least 15 of 10 micron thickness, or 20 when \< 10 micron thickness)or 1 tissue block must be available from the original diagnostic biopsy/surgery or from the biopsy/surgery recurrence * Participants who have undergone recent resection of recurrent or progressive tumor will be eligible provided at least 2 weeks has elapsed since surgery, and subjects have recovered from surgical-related trauma * Residual disease following resection of recurrent GBM or gliosarcoma is not mandated for eligibility into the study. Exclusion Criteria: * Participant has received a dosing schedule of temozolomide other than 75 mg/m2/day for 42 days during RT followed by adjuvant temozolomide at a dose of 150-200 mg/m2/day for 5 days of a 28-day schedule (standard dose adjustments for toxicity are allowed) * Any other anti-tumor agent other than standard surgical resection, RT and temozolomide prior to enrollment or during the study period * Received treatment with BCNU (Gliadel) wafers or GliaSite * Progressed prior to receiving at least 2 cycles of adjuvant temozolomide * Pregnant or intending to become pregnant during the study * In a situation or condition that, in the opinion of the Investigator, may interfere with optimal participation in the study * Participating in any other clinical study in which an investigational drug is prescribed * Allergic to or has sensitivity to the study drug or its excipients * History of any other cancer (except non-melanoma skin cancer or carcinoma in situ of the cervix), unless he/she is in complete remission and has not received treatment for that particular disease for the past 3 or more years