Inclusion Criteria:

- Male or female subject aged ≥ 18 to ≤ 70 years at the time of informed consent
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- Tumor tissue specimens taken from multimodal imaging-guided stereotactic biopsy must
be available for histopathological confirmation of GBM and potential subsequent
analysis of tissue molecular markers

- Newly diagnosed histologically proven supratentorial GBM (World Health Organization
[WHO] Grade IV)

- Subject with non-resectable GBM

- Available dynamic MRI and FET-PET scan prior to randomization

- Available Gd-MRI performed prior randomization

- ECOG Performance status of 0-2

- Stable or decreasing dose of steroids for >= 5 days prior to randomization

- Given written informed consent

Exclusion Criteria:

- Prior chemotherapy within the last 5 years

- Prior RTX of the head (except for low-dose radiotherapy for Tinea capitis)

- Gross total resection/partial resection (GBM surgery), placement of Gliadel® wafer

- Receiving concurrent investigational agents or receipt of an investigational agent
within the past 30 days prior to the first day of intensified imaging (W1D1)

- Prior systemic antiangiogenic therapy

- Inability to undergo dynamic MR or FET-PET imaging

- History of allergic reactions attributed to Gadolinium-based contrast agents for MRI,
compounds of similar chemical or biological composition

- Planned major surgery for other diseases

- History of recent peptic ulcer disease (endoscopically proven gastric ulcer, duodenal
ulcer, or esophageal ulcer) within 6 months prior to enrollment

- History of other malignant disease or acute malignant disease. Subjects with
curatively treated cervical carcinoma in situ or basal cell carcinoma of the skin, or
subjects who have been free of other malignancies for ≥ 5 years are eligible for this
study

- Current or history of bleeding disorders and/or history of thromboembolic events

- Clinically manifest myocardial insufficiency (NYHA III, IV) or history of myocardial
infarction during the past 6 months prior to enrollment, uncontrolled arterial
hypertension