Atezolizumab and Cabozantinib for the Treatment of Recurrent Glioblastoma

Inclusion Criteria: * Signed informed consent form (ICF) * Ability and willingness to comply with the requirements of the study protocol * Age \>= 18 years * Have histologically confirmed World Health Organization grade IV glioma (glioblastoma or gliosarcoma). Archival tissue will be required for diagnosis confirmation. Receipt of archival tissue is not required for the start of treatment * Patients must have been previously treated with radiation and temozolomide * Patients must be at least 12 weeks out from completion of concurrent chemoradiation * Have a performance status of \>= 60 on the Karnofsky performance status (KPS) * Patients at either first or second recurrence will be considered eligible * A baseline brain magnetic resonance imaging (MRI) obtained no more than 14 days prior to study enrollment * Absolute neutrophil count (ANC) \>= 1,500 /mcL * Platelets \>= 100,000 /mcL * Hemoglobin \>= 9 g/dL or \>= 5.6 mmol/L * Serum creatinine =\< 1.5 X upper limit of normal (ULN) OR measured or calculated creatinine clearance (glomerular filtration rate \[GFR\] can also be used in place of creatinine or creatinine clearance \[CrCl\]) \>= 60 mL/min for subject with creatinine levels \> 1.5 X institutional ULN * Creatinine clearance should be calculated per institutional standard * Urine protein/creatinine ratio (UPCR) =\< 1 mg/mg (=\< 113.2 mg/mmol) OR 24 hour (h) urine protein =\< 1g * Serum total bilirubin =\< 1.5 X ULN OR direct bilirubin =\< ULN for subjects with tota…