Study of IDO Inhibitor and Temozolomide for Adult Patients With Primary Malignant Brain Tumors

Inclusion Criteria: * Histologically proven intracranial glioblastoma multiforme (WHO grade IV glioma) or gliosarcoma. In addition, the Phase 1b cohort will include patients with progressive WHO grade III glioma. * Patients will be eligible if the original histology was lower grade glioma and a subsequent diagnosis of glioblastoma or gliosarcoma is made. * Unequivocal radiographic evidence for tumor progression by MRI. It is understood that some patients may be resected prior to enrolling onto protocol * Patients must have completed a course of radiation therapy and at least 2 adjuvant cycles of temozolomide for the phase 2 component. * Patients enrolling onto Cohort 2b who have been taken off bevacizumab must have had at least a 28 day washout from any previous administration of bevacizumab. It is preferred that patients who fail bevacizumab prior to trial entry remain on bevacizumab in the trial. * Prior temozolomide is not required for the phase 1 component; prior radiation is required for the phase 1 arm. * Patients must be on a steroid dose less than or equal to 2 mg of dexamethasone daily (or equivalent), and this dose must not have increased for at least 14 days prior to obtaining the enrollment. * ECOG performance status ≤1 or Karnofsky ≥70%. * Age between 16 * Must be 28 days from the administration of any investigational agent or prior cytotoxic therapy with the following exceptions: * Must be 14 days from administration of non-cytotoxic agents (e.g., bevacizumab (except COHORT 2b), interferon, tamoxifen, thalidomide, cis-retinoic acid, tyrosine kinase inhibitor, etc.). Exclusion Criteria: * Prior invasive malignancy that is not low-grade glioma, high-grade glioma, glioblastoma, or gliosarcoma (except non-melanomatous skin cancer or carcinoma in situ of the cervix) unless the patient has been disease free and off therapy for that disease for a minimum of 3 years. * Patients on the phase 2 portion of the study may not have more than 2 prior regimens for recurrent disease for glioblastoma/gliosarcoma. Patients on the phase 1 portion of the study may not have had more than 3 prior regimens. * Systemic corticosteroid therapy \> 2 mg of dexamethasone daily (or equivalent) at study enrollment. * Active or history of autoimmune disease