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TPS2577 Background: Patients diagnosed with malignant high-grade gliomas (WHO grade III-IV) experience significant morbidity and mortality associated with these cancers. While the mainstay of therapy for patients with newly diagnosed high-grade glioma is surgery followed by concurrent chemotherapy and radiation therapy (RT), the outcomes remain very poor. BMX-001 (MnTnBuOE-2-PyP5+) is a metalloporphyrin with differential action in response to radiation therapy and chemotherapy-induced oxidative stress. Early preclinical studies demonstrated BMX-001’s ability to act as a radioprotectant to healthy tissue such as a central nervous white matter and as a radiosensitizer to cancer cells, in particular, human glioblastoma xenografts. We evaluated the safety of BMX-001 in combination with concurrent RT and temozolomide (TMZ) in a phase I study of newly diagnosed high-grade glioma patients, and we found that BMX-001 is safe and well-tolerated in this population. The maximum tolerated dose of BMX-001 during concurrent RT and TMZ was determined to be 28 mg delivered subcutaneously (SC) followed by 16 biweekly SC doses at 14 mg (Peters et al., Neuro-Oncology 2018). Methods: For this multi-site, open-label, phase II study (NCT02655601), we will randomize approximately 160 patients 1:1 to concurrent RT and TMZ with BMX-001 versus concurrent RT and TMZ alone. Key eligibility criteria include newly diagnosed histologically confirmed high-grade glioma (WHO III-IV), 18 ≥ years, and Karnofsky performance status ≥ 70%. The primary endpoint is overall survival. Secondary endpoints include cognitive performance as assessed by standardized cognitive testing, bone marrow protection, safety and tolerability, progression-free survival, overall tumor response rate, and plasma pharmacokinetics. Exploratory endpoints are health-related quality of life (as assessed by Functional Assessment of Cancer Therapy–Brain, Functional Assessment of Cancer Therapy-Cognition, and Functional Assessment of Chronic Illness Therapy-Fatigue), qualitative hair loss, and white matter integrity (as measured by MRI diffusion tensor/susceptibility imaging). Since November 2018, this phase II study has enrolled 64 of 160 high-grade glioma patients at six sites with future sites planned to be implemented. Clinical trial information: NCT02655601 .

2024 Background: Tumor hypoxia is a potent mediator of treatment resistance because of the negative impact on the efficacy of radiation and associated poor tumor delivery of cytotoxic chemotherapy....

TPS10635 Background: Glioblastoma (GBM) is an aggressive type of primary malignant brain tumor and despite treatment with surgery, radiation, and temozolomide (TMZ) chemotherapy, median overall survival (OS) remains poor. A pathologic hallmark of GBM is tumor necrosis, a suspected result from endogenous tumor hypoxia. Angiogenesis is stimulated by hypoxia-driven signaling cascades and is required for tumor proliferation. The inefficient blood supply of these hypoxic tumors also limits the efficacy of chemotherapy and radiotherapy. Surviving hypoxic tumor cells may be selected out and proliferate as a more aggressive tumor subtype, therefore hindering OS. 18F-Fluoromisonidazole (FMISO) is a PET radiotracer whose uptake in hypoxic tissues can be measured radiographically. The degree of tumor hypoxia has been negatively associated with time to tumor progression and survival (Spence et al, 2008). Knowledge of the degree/distribution of tumor hypoxia by PET uptake and perfusion MRI parameters may provide prognostic information and help guide therapy for patients with GBM. Methods: In this phase II prospective single arm multi-institution study, patients will undergo baseline FMISO PET and MR imaging two weeks prior to chemoradiotherapy (CRT). A subset of patients will receive a second FMISO PET one week prior to CRT to assess reproducibility. Clinical outcomes of OS and 6-month progression-free survival (PFS-6) will be correlated to PET and MRI parameters. Eligibility: Pathologically confirmed GBM with residual tumor after surgery (including T2/FLAIR hyperintensity consistent with tumor) scheduled to receive standard fractionated radiation therapy and temozolomide alone or with an anti-VEGF agent or PARP inhibitor. Current enrollment: 22 patients of 50 sample size Contact information: Please contact the PI, Elizabeth R. Gerstner, MD ( egerstner@partners.org ) for additional information. Significance: With a better understanding of the extent of tumor hypoxia and changes in hypoxia levels from treatment, more effective therapies could be developed to inhibit GBM growth, target hypoxic areas and individualize patient care.

2058 Background: To determine the prognostic significance of changes in parameters derived from diffusion tensor imaging (DTI) that occur in response to combination chemotherapy with the antiangiogenesis agent bevacizumab (BEV) in patients with recurrent glioblastoma multiforme (GBM). Methods: 16 patients (10 men, 6 women; age range 38–62 years) with recurrent GBM underwent serial 1.5T MR imaging. Axial single-shot echo planar DTI (TR/TE 6000/100; flip angle 90 degrees; voxel: 1.72 x 1.72 x 5mm; b value of 1000 sec/mm2; 12 directions) was obtained on scans performed 3 days and 1 day prior to and 1 day after initiation of therapy with BEV and irinotecan (CPT-11). Clinical follow-up and survival status was documented up to 20 months after the date of initial MR imaging. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were aligned to whole brain contrast-enhanced 3D FLASH and 3D FLAIR image volumes (1 mm isotropic voxels) using a rigid body normalized mutual information algorithm. Based on two pre-treatment scans, the 95% confidence limits for change (95%CL) in ADC and FA were calculated in volumes of tumor-related contrast-enhancement (TRE) and FLAIR signal abnormality (FSA). A patient was considered to have a change in FA or ADC after therapy if the difference between the pre- and post-treatment values was greater than the 95% CL for that parameter. Progression was defined on contrast-enhanced MRI using MacDonald criteria by neuro-oncologists blinded to the DTI findings. Survival was compared using the log rank test. Results: DTI detected a change in ADC within FSA after therapy in three patients (2 increased, 1 decreased). Patients with a change in ADC within FSA had significantly shorter overall (p < 0.0012) and progression free (p < 0.015) survival than those with no change. Median survival in the patient group with a change in ADC was 24.7 (95% CI [17.3, 39.4]) weeks and 56.4 (95% CI [41.7, 96]) weeks in those patients with no change. Conclusions: In patients with GBM treated with BEV and CPT-11, a change in ADC after therapy in areas of FSA is associated with decreased survival. Parameters derived from DTI may, therefore, potentially serve as early markers of treatment failure in patients with GBM. [Table: see text]

2026 Background: DCE-MRI can determine vascular permeability using Ktrans, a volume transfer constant of contrast agent between blood plasma and the extravascular extracellular space. We report a p...

2029 Background: Significant responses seen in GBM patients treated with BEV and CPT-11 generated the need to develop ways to predict clinical benefit. DCE-MRI can be used to evaluate the microvasculature within tumors. DCE-MRI uses Ktrans, a volume transfer constant of contrast agent between blood plasma and the extravascular extracellular space, to determine vascular permeability. A 50% reduction in Ktrans is clinically meaningful. We report a phase II trial to determine the correlation between vascular permeability and radiographic response in GBM patients treated with the combination. Methods: Eligibility included patients with recurrent GBM. Both agents were given every 14 days. All patients received BEV at 10 mg/kg IV. CPT-11 was dosed at 340 mg/m2 for patients on enzyme inducing antiepileptic drugs (EIAED) and 125 mg/m2 for patients not on EIAED. Radiographic responses were assessed every 6 weeks. DCE-MRIs were performed before administration of chemotherapy, one day after treatment and after the first cycle. The primary endpoint was to examine the effect of BEV and CPT-11 treatment on vascular permeability as measured by percent change from baseline in Ktrans. Results: Twenty patients were enrolled, with a median age of 49.5 years. Fifteen patients are assessable for response. Best responses include one patient with complete response, 8 with partial response (response rate=60%), six patients with stable disease, and one with disease progression. Ktrans values are available for 13 patients; data are not available for seven patients (too early: 4, technical difficulty: 3). A reduction in Ktrans by 50% was observed in 6 patients one day after treatment and in 12 patients at the end of cycle 1. Changes in Ktrans value were highly correlated with the percentage decline in tumor volume from baseline to end of cycle one (Pearson correlation = 0.82; p=0.0006). Fifteen patients are still on study. Five patients came off due to disease progression. Conclusions: The utilization of DCE-MRI to determine a reduction in vascular permeability following a combination of BEV and CPT-11 is feasible and correlates significantly with the degree of tumor volume decrease. No significant financial relationships to disclose.