Inclusion Criteria:

          -  At least 18 years of age

          -  Ability to understand the purposes and risks of the study and has signed a written
             informed consent form approved by the investigator's IRB/Ethics Committee

          -  Histologically confirmed IDH wild-type (de novo) GBM

          -  Progression following standard combined modality treatment with radiation and
             temozolomide chemotherapy if O6-Methylguanine-DNA Methyltransferase (MGMT) methylated;
             prior temozolomide is not required for MGMT unmethylated, but patient must have
             received standard doses of radiation. Inclusion of additional investigational therapy
             with standard therapy is not exclusionary. No additional lines of therapy.

          -  Patients may have had been operated for recurrence, but if operated must have had
             surgery a minimum of 2 weeks prior to enrollment and have an MRI completed within 48
             hours following surgery.

          -  No radiotherapy within the three months prior to the diagnosis of progression.

          -  Willingness to forego tumor treatment field (Optune) therapy during participation in
             the study.

          -  Stable or decreasing dosage of steroids for 7 days prior to the baseline MRI scan.

          -  Recovered from toxicities of prior therapy to grade 0 or 1, except for neuropathy
             (≤Grade 2) and alopecia.

          -  ECOG performance status ≤ 2

          -  Life expectancy of at least 6 months

          -  Acceptable liver function:

               1. Bilirubin ≤ 1.5 times upper limit of normal

               2. AST (SGOT) and ALT (SGPT) ≤ 3.0 times upper limit of normal (ULN);

          -  Acceptable renal function:

             a. creatinine clearance ≥30 mL/minute according to the Cockcroft and Gault formula

          -  Acceptable hematologic status (without hematologic support):

               1. ANC ≥1500 cells/uL

               2. Platelet count ≥100,000/uL

               3. Hemoglobin ≥9.0 g/dL

          -  All women of childbearing potential must have a negative serum pregnancy test and male
             and female subjects must agree to use effective means of contraception (surgical
             sterilization or the use or barrier contraception with either a condom or diaphragm in
             conjunction with spermicidal gel or an IUD) with their partner from entry into the
             study through 6 months after the last dose

          -  Availability of biological material for central review and biomarker evaluation

        Exclusion Criteria:

          -  Prior treatment with bevacizumab or other VEGF inhibitors or VEGF-Receptor signaling
             inhibitors

          -  The subject is receiving warfarin (or other coumarin derivatives) and is unable to
             switch to low molecular weight heparin (LMWH) before the first dose of study drug.

          -  The subject has evidence of acute intracranial or intratumoral hemorrhage either by
             MRI or computerized tomography (CT) scan. Subjects with resolving hemorrhage changes,
             punctate hemorrhage, or hemosiderin are eligible.

          -  The subject is unable to undergo MRI scan (eg, has pacemaker).

          -  The subject has received enzyme-inducing anti-epileptic agents within 14 days of study
             drug (eg, carbamazepine, phenytoin, phenobarbital, primidone).

          -  The subject has not recovered to National Cancer Institute (NCI) Common Terminology
             Criteria for Adverse Events (CTCAE) 5.0 Grade ≤ 1 from AEs (except alopecia, anemia
             and lymphopenia) due to surgery, antineoplastic agents, investigational drugs, or
             other medications that were administered prior to study drug.

          -  The subject is pregnant or breast-feeding.

          -  The subject has serious intercurrent illness, such as:

               -  hypertension (two or more blood pressure [BP] readings performed at screening of
                  > 150 mmHg systolic or > 100 mmHg diastolic) despite optimal treatment

               -  non-healing wound, ulcer, or bone fracture

               -  significant cardiac arrhythmias

               -  untreated hypothyroidism

               -  unhealed rectal or peri-rectal abscess

               -  uncontrolled active infection

               -  symptomatic congestive heart failure or unstable angina pectoris within 3 months
                  prior study drug any history of cardiac arrhythmia or heart block

               -  stroke or transient ischemic attack within 6 months

          -  The subject has received any of the following prior anticancer therapy:

               -  Non-standard radiation therapy such as brachytherapy, systemic radioisotope
                  therapy (RIT), or intra-operative radiotherapy (IORT). Note: stereotactic
                  radiosurgery (SRS) is allowed

               -  Systemic therapy (including investigational agents and small-molecule kinase
                  inhibitors) or non-cytotoxic hormonal therapy (eg, tamoxifen) within 7 days or 5
                  half-lives, whichever is shorter, prior first dose of study drug

               -  Biologic agents (antibodies, immune modulators, vaccines, cytokines) within 21
                  days prior to first dose of study drug

               -  Nitrosoureas or mitomycin C within 42 days, or metronomic/protracted low-dose
                  chemotherapy within 14 days, or other cytotoxic chemotherapy within 28 days,
                  prior to first dose of study drug

               -  Prior treatment with carmustine wafers

          -  Patients with radiographically apparent leptomeningeal involvement are excluded