Nativis Voyager for Newly Diagnosed GBM

Inclusion Criteria: * There is pathological evidence of GBM using World Health Organization (WHO) classification. * Subject received maximal debulking surgery. Patients may enroll in the study if received Gliadel wafers before entering the trial. Any additional treatments received prior to enrollment will be considered an exclusion. * Subject must have at least one measurable lesion per RANO. * Subject is at least 18 years of age. * Subject has a Karnofsky Performance Scale (KPS) ≥ 60. * Subject has life expectancy \> 3 months. * Subject has adequate organ and marrow function; see note 1. * Subject able to start treatment at least 28 days from tumor resection surgery. * Subject has provided signed informed consent. Exclusion Criteria: * Subject has progressive disease per RANO. If pseudoprogression is suspected, additional imaging studies must be performed to rule out true progression. * Evidence of increased intracranial pressure (midline shift \> 5mm, clinically significant papilledema, vomiting and nausea or reduced level of consciousness) * Subject is currently being treated with Optune. * Subject is currently being treated with other investigational agents. * Subject has not sufficiently recovered from prior surgery in the opinion of the investigator. * Subject has significant co-morbidities at baseline which would prevent radiotherapy and/or temozolomide treatment. * Subject has history of hypersensitivity reaction to temozolomide or a history of hypersensitivity to dacarbazine (DTIC). * Subject has a clinically significant electrolyte abnormality. * Subject has an active implantable (e.g., neurostimulator, pacemaker) or other electromagnetic device that is incompatible with MRI. Subjects with programmable shunt are excluded from the study. * Subject has a metal implant, including a stent, in the head or neck that is incompatible with MRI. * Subject is known to be HIV positive. * Subject is pregnant, nursing or intends to become pregnant during the study period. * Subject is participating in other potentially confounding investigational research. * Subject has any condition that at the discretion of the investigator would preclude participation in the study. * Subject is unable or unwilling to comply with the protocol-required follow-up schedule.