• Signed informed consent must be obtained prior to participation in the study

• Age \>= 18 years

• Histologically confirmed glioblastoma according to WHO classification established following either a surgical resection or biopsy

• Participants who are receiving corticosteroid treatment with dexamethasone, must be treated with a dose of =\<4 mg/day (or other corticosteroids at equivalent dose) for a minimum of 7 days before initiation of study treatment

• Adequate bone marrow and organ function as defined by the following laboratory values obtained prior to receiving the first study treatment:

‣ Absolute Neutrophil Count (ANC) \>= 1.5 x 10\^9/L

⁃ Platelet count \>= 100 x 10\^9/L

⁃ Hemoglobin \>= 10.0 g/dL

⁃ Creatinine clearance \>= 60 mL/min calculated by the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation .

⁃ Aspartate transaminase (AST) or Alanine transaminase (ALT) =\< 3.0 x ULN

⁃ Total bilirubin (TBIL) \< 1.5 × ULN (any elevated bilirubin should be asymptomatic at enrollment) except for participants with Gilbert's syndrome who may only be included if the total bilirubin is =\< 3.0 × ULN or direct bilirubin =\< 1.5 × ULN

⁃ Serum lipase ≤ 1.5 x ULN. For serum lipase \> ULN - =\< 1.5 x ULN, value must be considered not clinically significant and not associated with risk factors for acute pancreatitis

∙ 9\. Availability of tumor tissue representative of glioblastoma from definitive surgery or biopsy, to support biomarker analysis 10. Presence of gadolinium enhancement at the tumor region in the pre-surgery MRI

∙ 14\. If a second surgery is performed for glioblastoma recurrence, the following criteria must be met:

• residual and measurable disease post-surgery is not required but surgery must have confirmed the recurrence diagnosis by MRI.

• surgery completed at least 2 weeks prior to study treatment initiation, with post-surgery recovery without any complications related to surgical procedure.