PH Weighted Chemical Exchange Saturation Transfer Based Surgical Resections of Glioblastoma

Current standard of care therapy and all FDA approved adjuvant therapy for glioblastoma continue to provide less than 12 months of progression free survival (PFS) and less than 24 months of overall survival (OS). There is an extreme need for any novel therapy against glioblastoma that increases progression free survival and overall survival in patients diagnosed with this invasive form of cancer. A significant reason for such a poor prognosis is the infiltrative nature of this tumor in non-enhancing regions (NE) beyond the central contrast-enhancing (CE) portion of tumor, which is difficult to visualize and treat with surgical, medical, or radiotherapeutic means.

Since tumor cells exhibit abnormal metabolic behavior leading to extracellular acidification, we theorize a newly developed pH-sensitive MRI technique called amine chemical exchange saturation transfer echoplanar imaging (CEST-EPI) may identify infiltrating NE tumor beyond what is clear on standard MRI with gadolinium contrast. This phase I safety study will use use intraoperative CEST-EPI guided resections in glioblastoma at increasing distances from areas of CE tumor to test whether this technique is safe and can remove additional areas of infiltrative NE tumor.

The primary objective of this study is to assess the safety of pH-sensitive amine CEST-EPI guided resections for glioblastoma.The secondary objectives of this study include:

1. A preliminary efficacy analysis of CEST-EPI guided resections in extending progression free and overall survival.
2. To confirm that resected tissue obtained from pH-sensitive amine CEST-EPI guided resections contain infiltrating NE tumor.

The primary endpoint for this study will be safety of resecting "CEST positive", acidic regions within T2 hyperintense regions of glioblastoma thought to contain active NE tumor at increasing distances from contrast enhancing tumor with development of a recommended maximal tolerated resection.

1. At the maximal tolerated resection, a preliminary efficacy study with endpoints of progression free survival (as defined by RANO Resect 2.0) 1 and overall survival.
2. Quantitation of infilitrating tumor burden on CEST-EPI resected tissue using immunohistochemical staining.

12 patients up to 24 patients based on resection limiting toxicities with potential expansion of up to 16 patients at the maximum tolerated resection.

Inclusion Criteria:

1. Must be able to provide written informed consent
2. Male or female > 18 years of age
3. Karnofsky Performance Scale (KPS) > 70 (indicating good performance status).
4. Individuals with suspected, newly diagnosed or recurrent IDH wild type WHO IV glioblastoma (intraxial, expansile contrast-enhancing mass without evidence of metastatic disease. This will be reviewed by UCLA neuroradiology to only include patients with high likelihood of GBM)

Exclusion Criteria:

1. Pediatric patients
2. Diagnostic uncertainty (reviewed by UCLA neuroradiology history extracranial malignancy or autoimmune disease)
3. Medical conditions that make patients a poor candidate for anesthesia and/or surgery (decision for surgery will follow standard pre-operative clearance guidelines and will not differ for this specific study from standard of care treatment plan)
4. Involvement of eloquent areas (as defined by MRI signal clearly involving areas that would lead to a qualifying neurologic deficit as defined in surgical limiting toxicity - this will specifically include: 1) primary motor cortex, 2) primary sensory cortex, 3) sensorimotor fibers as defined on pre-operative diffusion tensor imaging, 4) primary language areas (Broca, Wernicke), 5) arcuate fasiculus as defined on pre-operative diffusion tensor imaging Pre-operative: Standard of care pre-operative MRI including perfusion and pH-weighted amine CEST-EPI (which will add up to 15 minutes of scan time) for a single pre-operative exam prior to surgery.

Surgery: 1 day (subjects to be admitted to the hospital) Follow-up: inpatient stay (1-3 days), 2 week clinical assessment (outpatient post-op clinic visit). MRI and clinical assessment at 4 weeks (end of resection limited toxicity window). Following this, there will be standard of care follow up with MRI and clinical assessment starting at 8 weeks +/- 4 weeks (per RANO 2.0). 1

Total study duration for recruitment, enrollment, and study completion of all subjects is up to 2 years.

Single-arm, surgical resection escalation safety trial with a preliminary efficacy study at the maximal tolerated resection

This safety evaluation will mimic a phase 1 dose escalation safety study using a rule based approach on based on a i3+3 design.2 Using standard of care resection of contrast enhancement as the baseline, we will begin with 3 subjects with maximal resection + "CEST positive" areas 0.7 cm from the contrast enhancing boundary within areas of T2 hyperintensity. If there is not > 1 pre-determined resection limiting toxicity (RLT, defined below) in this cohort, the r