Newly Diagnosed Inclusion Criteria:

          -  Age ≥ 18 years.

          -  Histologically confirmed Grade IV GBM/gliosarcoma established following either a
             surgical resection or biopsy.

          -  Karnofsky performance status ≥ 60% performed within a 14-day window prior to
             randomization.

          -  Availability of tumor tissue representative of GBM from definitive surgery or biopsy.

        Recurrent Inclusion Criteria:

          -  Age ≥ 18 years.

          -  Histologically confirmed GBM/gliosarcoma (WHO criteria; non-IDH R132H mutant) at first
             or second recurrence after initial standard, control or experimental therapy that
             includes at a minimum Radiation Therapy (RT).

          -  Evidence of recurrent disease (RD) demonstrated by disease progression using slightly
             modified Response Assessment in Neuro-Oncology (RANO) criteria.

          -  Karnofsky performance status ≥ 70% performed within a 14-day window prior to
             randomization.

          -  Availability of tumor tissue representative of GBM from initial definitive surgery
             and/or, recurrent surgery, if performed.

        Newly Diagnosed Exclusion Criteria:

          -  Any prior treatment for glioma including: prior prolifeprospan 20 with carmustine
             wafer; prior intracerebral agent; prior radiation treatment for GBM or lower-grade
             glioma; prior chemotherapy or immunotherapy for GBM or lower-grade glioma.

          -  Receiving additional, concurrent, active therapy for GBM outside of the trial

          -  Extensive leptomeningeal disease.

          -  QTc > 450 msec if male and QTc > 470 msec if female.

          -  History of another malignancy in the previous 3 years, with a disease-free interval of
             < 3 years. Patients with prior history of in situ cancer or basal or squamous cell
             skin cancer are eligible.

        Recurrent Exclusion Criteria:

          -  Early disease progression prior to 3 months (12 weeks) from the completion of RT.

          -  More than 2 prior lines for chemotherapy administration. (NOTE: In the 1st line
             adjuvant setting, combination of Temozolomide (TMZ) with an experimental agent, is
             considered one line of chemotherapy.)

          -  Any prior treatment with bevacizumab or other VEG)- or VEGF receptor-mediated targeted
             agent.

          -  Any prior treatment with prolifeprospan 20 with carmustine wafer.

          -  Any prior treatment with an intracerebral agent.

          -  Receiving additional, concurrent, active therapy for GBM outside of the trial

          -  Extensive leptomeningeal disease.

          -  QTc > 450 msec if male and QTc > 470 msec if female.

          -  History of another malignancy in the previous 2 years, with a disease-free interval of
             < 2 years. Participant with prior history of in situ cancer or basal or squamous cell
             skin cancer are eligible.