INO-5401 and INO-9012 delivered intramuscularly (IM) with electroporation (EP) in combination with cemiplimab (REGN2810) in newly diagnosed glioblastoma (GBM): Interim results

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Background: Novel T cell-enabling therapies, in combination with checkpoint inhibition, may improve OS in GBM. INO-5401 (synthetic DNA plasmids encoding for hTERT, WT-1 and PSMA), plus INO-9012 (synthetic DNA plasmid encoding IL-12), with the PD-1 checkpoint inhibitor cemiplimab, is given to patients with newly-diagnosed GBM to evaluate tolerability, efficacy and immunogenicity of the combination. Methods: Phase I/II, single arm, 2 cohort study (A: MGMT unmethylated, B: MGMT methylated). The primary endpoint is safety; efficacy and immunogenicity are secondary. Nine mg INO-5401 plus 1 mg INO-9012 (every 3 weeks for 4 doses, then Q9W) is given with EP by CELLECTRA 2000 with cemiplimab (350 mg IV Q3W). RT is given as 40 Gy over 3 weeks. TMZ is given with radiation (all patients), followed by maintenance (Cohort B only). Results: Fifty two subjects were enrolled: 32 in Cohort A; 20 in Cohort B. 35% women and 90% white. Median age 60 years (range 19-78 years). Common Grade ≥3 AEs reported were: platelet count decreased (11.5%), tumor inflammation (7.7%), seizure (7.7%), ALT increased (7.7%), lymphocyte count decreased (7.7.%). One Grade 5 unrelated event of urosepsis was reported. Of 69 SAEs reported there was only 1 related to the combination therapy, Grade 1 pyrexia. 48% of subjects reported irAEs, most frequently ALT increased (9.6%), AST increased (7.7%), diarrhea (7.7%), pyrexia (7.7%) and tumor inflammation (7.7%). 71% of the reported SAEs and irAEs occurred within the first 12 weeks of treatment. OS at 12 months was 84.4% (95% CI 67.2, 94.7) in Cohort A; Cohort B will be presented at ASCO. ELISpot assessments demonstrated T cell responses to INO-5401. Flow cytometry demonstrated evidence of activated INO-5401-specific CD8+T cells with lytic potential (CD38+Prf+GrzA+) when compared with baseline, post-treatment in the majority of patients assayed. Conclusions: INO-5401 + INO-9012 in combination with cemiplimab and RT/TMZ has an acceptable safety profile, is immunogenic and may show a survival advantage in patients with newly-diagnosed GBM. OS18 data will be presented later this year. Clinical trial information: NCT03491683 .

Evaluating Surgical Resection Extent and Adjuvant Therapy in the Management of Gliosarcoma

Introduction: Gliosarcomas are clinically aggressive tumors, histologically distinct from glioblastoma. Data regarding the impact of extent of resection and post-operative adjuvant therapy on gliosarcoma outcomes are limited.

Methods: Patients with histologically confirmed gliosarcoma diagnosed between 1999 and 2019 were identified. Clinical, molecular, and radiographic data were assembled based on historical records. Comparisons of categorical variables used Pearson's Chi-square and Fisher's exact test while continuous values were compared using the Wilcoxon signed-rank test. Survival comparisons were assessed using Kaplan-Meier statistics and Cox regressions.

Results: Seventy-one gliosarcoma patients were identified. Secondary gliosarcoma was not associated with worse survival when compared to recurrent primary gliosarcoma (median survival 9.8 [3.8 to 21.0] months vs. 7.6 [1.0 to 35.7], p = 0.7493). On multivariable analysis, receipt of temozolomide (HR = 0.02, 95% CI 0.001–0.21) and achievement of gross total resection (GTR; HR = 0.13, 95% CI 0.02–0.77) were independently prognostic for improved progression-free survival (PFS) while only receipt of temozolomide was independently associated with extended overall survival (OS) (HR = 0.03, 95% CI 0.001–0.89). In patients receiving surgical resection followed by radiotherapy and concomitant temozolomide, achievement of GTR was significantly associated with improved PFS (median 32.97 [7.1–79.6] months vs. 5.45 [1.8–26.3], p = 0.0092) and OS (median 56.73 months [7.8–104.5] vs. 14.83 [3.8 to 29.1], p = 0.0252).

Conclusion: Multimodal therapy is associated with improved survival in gliosarcoma. Even in patients receiving aggressive post-operative multimodal management, total surgical removal of macroscopic disease remains important for optimal outcomes.

Macrophage Exclusion after Radiation Therapy (MERT): A First in Human Phase I/II Trial using a CXCR4 Inhibitor in Glioblastoma

PURPOSE

Preclinical studies have demonstrated that postirradiation tumor revascularization is dependent on a stromal cell-derived factor-1 (SDF-1)/C-X-C chemokine receptor type 4 (CXCR4)-driven process in which myeloid cells are recruited from bone marrow. Blocking this axis results in survival improvement in preclinical models of solid tumors, including glioblastoma (GBM). We conducted a phase I/II study to determine the safety and efficacy of Macrophage Exclusion after Radiation Therapy (MERT) using the reversible CXCR4 inhibitor plerixafor in patients with newly diagnosed glioblastoma.

PATIENTS AND METHODS

We enrolled nine patients in the phase I study and an additional 20 patients in phase II using a modified toxicity probability interval (mTPI) design. Plerixafor was continuously infused intravenously via a peripherally inserted central catheter (PICC) line for 4 consecutive weeks beginning at day 35 of conventional treatment with concurrent chemoradiation. Blood serum samples were obtained for pharmacokinetic analysis. Additional studies included relative cerebral blood volume (rCBV) analysis using MRI and histopathology analysis of recurrent tumors.

RESULTS

Plerixafor was well tolerated with no drug-attributable grade 3 toxicities observed. At the maximum dose of 400 μg/kg/day, biomarker analysis found suprathreshold plerixafor serum levels and an increase in plasma SDF-1 levels. Median overall survival was 21.3 months [95% confidence interval (CI), 15.9-NA] with a progression-free survival of 14.5 months (95% CI, 11.9-NA). MRI and histopathology support the mechanism of action to inhibit postirradiation tumor revascularization.

CONCLUSIONS

Infusion of the CXCR4 inhibitor plerixafor was well tolerated as an adjunct to standard chemoirradiation in patients with newly diagnosed GBM and improves local control of tumor recurrences.

NIMG-36. EVALUATION OF [18F]DASA-23 FOR NON-INVASIVE MEASUREMENT OF ABERRANTLY EXPRESSED PYRUVATE KINASE M2 IN GLIOMA: FIRST-IN-HUMAN STUDY

OBJECTIVES

We developed 1-((2-fluoro-6-(fluoro-[18F])phenyl)sulfonyl)-4-((4-methoxyphenyl)sulfonyl)piperazine ([18F]DASA-23) as a novel radiopharmaceutical to measure pyruvate kinase M2 levels by positron emission tomography (PET). PKM2 catalyzes the final step in glycolysis, the key process of tumor metabolism. PKM2 is preferentially expressed by glioblastoma (GBM) cells with minimal expression in the healthy brain, making it an important biomarker of cancer glycolytic re-programming. Here, we report the first evaluation of [18F]DASA-23 in human healthy volunteers and subjects with low-grade (LGG) and high-grade glioma (HGG).

METHODS

[18F]DASA-23 was synthesized under GMP conditions. Brain [18F]DASA-23 PET/MRI scans (3T) were performed in human healthy volunteers (n=5) and subjects with LGG (n=3) and HGG (n=2). The PET imaging duration was 60 min and standardized uptake value (SUV) calculations were performed on the 30–60 min summed images. The maximum SUV in the tumor (TumorSUVmax) and contralateral white matter (WMSUVmax) were calculated.

RESULTS

[18F]DASA-23 specific activity was 2961±873 mCi/µmol (n=10) with radiochemical purity >95%, injected mass of 1.8±0.7 mcg, and dose of 0.3±0.02 mcg per kg body weight. In healthy volunteers, [18F]DASA-23 crossed the intact blood-brain barrier and was rapidly cleared through the bladder and also showed uptake in the gallbladder, liver, and intestines over time. [18F]DASA-23 was found to be intact in plasma up to 10 min post-injection and 75% intact at 30 min post-injection. In subjects with glioma, TumorSUVmax was significantly greater in HGG (2.2±0.4, n=2) compared to LGG (0.8±0.3m n=3), p=0.02. In this early human series, the normalized ratio of TumorSUVmax/WMSUVmax was not significantly different between subjects with HGG (2.0±0.6) and LGG (1.0±0.4), p=0.1.

CONCLUSION

[18F]DASA-23 is a promising new imaging agent for the non-invasive delineation of LGG and HGG based on aberrantly expressed PKM2. An ongoing study is evaluating the utility of this agent in additional patients with intracranial malignancies (NCT03539731).

CMET-27. EVALUATION OF DYNAMIN 2 (DNM2) AS A THERAPEUTIC TARGET IN LEPTOMENINGEAL METASTATIC DISEASE

Leptomeningeal metastasis (LM), a spread of cancer to the meninges and cerebrospinal fluid, carries extremely poor prognosis due to fast progression and no effective treatment. Given that LM mostly develops in specific types of cancer, notably melanoma, breast and lung cancer, it is likely that predisposition for LMD is shaped by specific genetic footprints and/or anti-cancer therapies. In this regard, it is interesting that among all breast cancers the triple-negative (i.e. estrogen and progesterone receptor-negative and HER2 overexpression-negative) breast cancer (TNBC) type develops a disproportionally high percentage of LM, accounting for the majority (~40%) of all breast cancer LM cases. TNBCs trace their origin to the genomic instability stemming from defects in DNA repair (notably homology-directed repair, HDR). We have recently shown that the efficiency of HDR depends on dynamin 2 (DNM2) best known for its role in endocytic protein trafficking. Higher DNM2 was associated with more efficient HDR and the resistance to DNA-crosslinking chemotherapy. Importantly, elevated DNM2 was associated with lower relapse-free survival and shorter times to relapse after chemotherapy only in TNBCs and not in other types of breast cancer. As DNM2 also fuels migration and invasion, the cells with high DNM2 are not only the most resistant to chemotherapy but also are the most mobile, and thus may represent the core population of LM. Here we test the inhibition of the DNM2-dependent endocytic trafficking as a potential therapeutic strategy to halt LM in TNBC. As a model of LM we use the human-in-mouse model of brain metastasis based on internal carotid injection of MDA-MB-231-BR3 cells, which we have shown to faithfully recapitulate human LM. We show that DNM2 knockdown delays metastatic spread to the brain and potentiates the effect of DNA-crosslinking chemotherapeutic cyclophosphamide, providing justification for further testing of DNM2 inhibitors for targeted therapy of LM.

ACTR-59. A PHASE 1 STUDY OF BPM31510 PLUS VITAMIN K IN SUBJECTS WITH HIGH-GRADE GLIOMA THAT HAS RECURRED ON A BEVACIZUMAB-CONTAINING REGIMEN

BACKGROUND

High-grade gliomas (HGG) are characterized by dysregulated metabolism, utilizing glycolysis for energy production to support unrestricted growth. BPM 31510, an ubidecarenone (coenzyme Q10) containing lipid nanodispersion, causes a switch in cancer energy sourcing from glycolysis towards mitochondrial oxidative phosphorylation in vitro, reversing the Warburg effect and suggesting potential as an anti-tumor agent. The current study is a phase I study of BPM31510 + vitamin K in GB with tumor growth after bevacizumab (BEV).

METHODS

This is an open-label phase I study of BPM31510 continuous infusion with weekly vitamin K (10mg IM) in HGG patients using an mTPI design, starting at 110mg/kg, allowing for a single dose de-escalation and 2 dose-escalations. Patients had received first-line ChemoRadiation and were in recurrence following a BEV containing regimen.

RESULTS

9 eligible and evaluable patients completed the 28 day DLT period. 8 patients had primary GB, 1 had anaplastic astrocytoma with confirmed pathologic transformation to GB. Median age was 55 years (27–67) and median KPS 70 (60–90) at enrollment. 4 patients were treated at the highest dose 171mg/kg, where there was a single DLT: Grade 3 AST & ALT. The most common grade 1–2 AEs possibly, probably or definitely related to drug were elevated AST, rash, and fatigue, each occurring in 3 patients. Median OS for 9 eligible/evaluable patients was 128 days (95% CI: 48–209) while PFS was 34 days (CI of mean 8.9). 3 patients are currently alive; 2 patients have survived >1 year. PK/PD data are being processed and will be presented.

CONCLUSION

This study confirms that BPM 31510 + vitamin K is safe and feasible in treatment-refractory HGG patients. Though this study demonstrates safety at 171mg/kg, the proposed dose for future studies in GB, based on additional pre-clinical and non-GB clinical data is 88mg/kg.

COMP-08. COMPREHENSIVE RNA ANALYSIS OF CEREBROSPINAL FLUID FROM LEPTOMENINGEAL METASTASES

Leptomeningeal metastases (LM), a diffuse form of brain metastases is rare and fatal progression of non-small cell lung cancer (NSCLC). In LM, metastatic cancer cells spread and resign on the brain meninges, the cerebrospinal fluid (CSF), cranial and spinal nerves. Rapid disease progression and scarce tissue availability hinder the progress of scientific study of LM and its treatment. To overcome the critical lack of tissue and to determine the genetic profile of NSCLC LM, we have developed methods to extract tumor-associated cell-free RNA from CSF, and isolated and sequenced circulating single cells from CSF. Herein, we used high throughput qPCR to target lung and brain-associated genes and identified NSCLC LM metastases-related RNA. Brain-specific gene signature (GFAP, NRGN, SNCB, ZBTB18) was detected in all CSF sample (control and metastases), whereas lung-specific genes (MUC1, SFTPB, SFTPD, SLC34A2) were detected in CSF of brain metastases patients. Normal, healthy CSF lacks cellular component, but CSF of patients with LM metastases inhabited with very low amount of circulating tumor cells. Single cells from CSF of 4 patients with NSCLC LM metastases were captured with microfluidic chip. Cells (n = 197) were clustered by significantly differential expressed genes demonstrating two distinct populations of white blood and tumor cells. These data identified specific cfRNA and single cell transcriptome profiles compared to normal cells or patients without NSCLC LM metastases, and highlighted metastases-associated carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) as highly expressed in patients with NSCLC LM metastases. CEACAM6 mRNA was detected in CSF of 86% of patients with NSCLC LM but not in the CSF of control patients. In vitro inhibition of CEACAM6 protein lead to decreased invasion in NSCLC cells which was rescued by overexpression of the protein. We have developed sensitive and robust techniques to leverage human CSF to study NSCLC LM.

Nodular Leptomeningeal Disease-A Distinct Pattern of Recurrence After Postresection Stereotactic Radiosurgery for Brain Metastases: A Multi-institutional Study of Interobserver Reliability

PURPOSE

For brain metastases, surgical resection with postoperative stereotactic radiosurgery is an emerging standard of care. Postoperative cavity stereotactic radiosurgery is associated with a specific, underrecognized pattern of intracranial recurrence, herein termed nodular leptomeningeal disease (nLMD), which is distinct from classical leptomeningeal disease. We hypothesized that there is poor consensus regarding the definition of LMD, and that a formal, self-guided training module will improve interrater reliability (IRR) and validity in diagnosing LMD.

METHODS AND MATERIALS

Twenty-two physicians at 16 institutions, including 15 physicians with central nervous system expertise, completed a 2-phase survey that included magnetic resonance imaging and treatment information for 30 patients. In the "pretraining" phase, physicians labeled cases using 3 patterns of recurrence commonly reported in prospective studies: local recurrence (LR), distant parenchymal recurrence (DR), and LMD. After a self-directed training module, participating physicians completed the "posttraining" phase and relabeled the 30 cases using the 4 following labels: LR, DR, classical leptomeningeal disease, and nLMD.

RESULTS

IRR increased 34% after training (Fleiss' Kappa K = 0.41 to K = 0.55, P < .001). IRR increased most among non-central nervous system specialists (+58%, P < .001). Before training, IRR was lowest for LMD (K = 0.33). After training, IRR increased across all recurrence subgroups and increased most for LMD (+67%). After training, ≥27% of cases initially labeled LR or DR were later recognized as nLMD.

CONCLUSIONS

This study highlights the large degree of inconsistency among clinicians in recognizing nLMD. Our findings demonstrate that a brief self-guided training module distinguishing nLMD can significantly improve IRR across all patterns of recurrence, and particularly in nLMD. To optimize outcomes reporting, prospective trials in brain metastases should incorporate central imaging review and investigator training.

Perfusion MRI-Based Fractional Tumor Burden Differentiates between Tumor and Treatment Effect in Recurrent Glioblastomas and Informs Clinical Decision-Making

BACKGROUND AND PURPOSE

Fractional tumor burden better correlates with histologic tumor volume fraction in treated glioblastoma than other perfusion metrics such as relative CBV. We defined fractional tumor burden classes with low and high blood volume to distinguish tumor from treatment effect and to determine whether fractional tumor burden can inform treatment-related decision-making.

MATERIALS AND METHODS

Forty-seven patients with high-grade gliomas (primarily glioblastoma) with recurrent contrast-enhancing lesions on DSC-MR imaging were retrospectively evaluated after surgical sampling. Histopathologic examination defined treatment effect versus tumor. Normalized relative CBV thresholds of 1.0 and 1.75 were used to define low, intermediate, and high fractional tumor burden classes in each histopathologically defined group. Performance was assessed with an area under the receiver operating characteristic curve. Consensus agreement among physician raters reporting hypothetic changes in treatment-related decisions based on fractional tumor burden was compared with actual real-time treatment decisions.

RESULTS

Mean lower fractional tumor burden, high fractional tumor burden, and relative CBV of the contrast-enhancing volume were significantly different between treatment effect and tumor (P = .002, P < .001, and P < .001), with tumor having significantly higher fractional tumor burden and relative CBV and lower fractional tumor burden. No significance was found with intermediate fractional tumor burden. Performance of the area under the receiver operating characteristic curve was the following: high fractional tumor burden, 0.85; low fractional tumor burden, 0.7; and relative CBV, 0.81. In comparing treatment decisions, there were disagreements in 7% of tumor and 44% of treatment effect cases; in the latter, all disagreements were in cases with scattered atypical cells.

CONCLUSIONS

High fractional tumor burden and low fractional tumor burden define fractions of the contrast-enhancing lesion volume with high and low blood volume, respectively, and can differentiate treatment effect from tumor in recurrent glioblastomas. Fractional tumor burden maps can also help to inform clinical decision-making.

Abstract 3608: BPM31510 exploits differential redox vulnerabilities between normal and glioblastoma cells to mediate its anti-cancer effect

Glioblastoma is an aggressive cancer, the proliferative capacity of which is correlated with glycolytic metabolism. BPM31510 is a novel formulation for delivery of supraphysiological levels of ubidecarenone to the mitochondria, enabling cancer specific metabolic switches. It is being studied in Phase I clinical trials versus a number of tumors, including glioma. Here, the effects of ubidecarenone on viability and redox homeostasis of glioma and non-tumorigenic cells was assessed using in vitro monoculture and coculture systems and an in vivo preclinical model. BPM31510 administration (50 mg/kg bid i.p., beginning 4-8 days post-inoculation) resulted in over a 20% long term survival rate in C6 tumor-bearing rats. We next compared BPM31510 effects in vitro between glioma lines (rat C6, human U251) and murine NIH3T3 fibroblasts, as a stromal control. In monocultures, decreased growth was observed in glioma lines and NIH3T3 with increasing BPM31510 doses; however, glioma lines were 2-fold more sensitive to BPM31510 compared to NIH3T3 cells (IC50 glioma lines: 230 µM vs IC50 NIH3T3: &gt;460 µM). To investigate the differential sensitivity to BPM31510, a coculture system was developed by coincubating 2 x 105 C6-GFP labeled cells and NIH3T3 cells. After 6 days of coculture, the percentage of C6 relative to NIH3T3 cells was lowest at doses of BPM31510 between 115 µM and 230 µM, evidence of greater sensitivity to BPM31510-induced cytotoxicity in the C6 glioma cells than the non-tumorigenic component. At higher doses, differential effects on cell viability were less apparent. The level of superoxide, a central reactive oxygen species important in redox homeostasis, was also assessed using Mitosox in cocultures. At a BPM31510 dose which resulted in maximal differential viability between C6 and NIH3T3 cells (230 μM), the maximal differential superoxide level was likewise greatest. The basal differential in Mitosox signal was 9-fold between C6 and NIH3T3 cells, and it increased to over 50-fold upon treatment with BPM31510 (230 μM), implying that BPM31510 exploits differential redox vulnerabilities between C6 and NIH3T3 to mediate its anti-cancer activity. At high doses of BPM31510, differential effects on superoxide levels were less apparent. In summary, BPM31510 has marked anti-cancer activity in rats implanted with C6 glioma, and its differential effects on the viability of normal and transformed cells are associated with maximal differences in BPM31510-induced superoxide production. Together, these data suggest that differential redox vulnerabilities between tumorigenic and non-tumorigenic cells may underpin the anti-cancer activity of BPM31510, and identification of in vivo correlates of redox indices may represent an avenue to improved measurement of anti-cancer efficacy as well as define patient populations responsive to BPM31510.

Citation Format: Jiaxin Sun, Seema Nagpal, Chirag Patel, Milton Merchant, Tiachang Jang, Anne R. Diers, Shiva Kazerounian, Stephane Gesta, Niven R. Narain, Rangaprasad Sarangarajan, Lawrence Recht. BPM31510 exploits differential redox vulnerabilities between normal and glioblastoma cells to mediate its anti-cancer effect [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3608.

QIM19-128: Improving Oral Chemotherapy Safety in Adult Neuro-Oncology Clinics

Background: The development of oral chemotherapies (OC) have transformed cancer care for millions of patients. Most patients with brain tumors have temozolomide (TMZ) delivered to their home. While this has improved the patient experience, it presents significant challenges to safety of prescription, administration, and side effect monitoring. While there are guidelines for documentation, there is not a best practices system for managing OC. This project identified areas of latent errors and implemented a standardized process for OC management. Methods: After review of the literature, we developed a process map for our institution’s practice and performed hazard analysis. We then evaluated the process at 3 other neuro-oncology practices. Based on these evaluations, changes were implemented at several stages (Table 1). Objective binary measures that could be recorded for every TMZ prescription were collected by chart review of the 6 months prior to process change. These measures were monitored every 2 weeks after process change implementation using run charts. A baseline process mean was calculated for each measure from the 6 months before program implementation. Successful change implementation was defined as 7 consecutive 2-week averages that were continually on one side of the process mean. Results: At the time of this abstract submission, we had successfully reduced refills for OC and increased documentation of dose calculation and dose ordered. There is improvement in independent dose calculation by 2 providers and dedicated chemotherapy teaching visits; however, these have not yet reached criteria for process change. Additionally, oral chemotherapy order sets were created in the electronic medical records system and an on-site specialty pharmacy was added as another safety measure in OC management. Conclusions: This project used published studies and multi-institutional process mapping and hazard analysis to implement a standardized ordering of TMZ for patients with brain tumors. This process can be implemented for OC management in other oncology practices.

Current State of Immunotherapy for Treatment of Glioblastoma

OPINION STATEMENT

At this time, there are no FDA-approved immune therapies for glioblastoma (GBM) despite many unique therapies currently in clinical trials. GBM is a highly immunosuppressive tumor and there are limitations to a safe immune response in the central nervous system. To date, there have been several failures of phase 3 immune therapy clinical trials in GBM. These trials have targeted single components of an antitumor immune response. Learning from these failures, the future of immunotherapy for GBM appears most hopeful for combination of immune therapies to overcome the profound immunosuppression of this disease. Understanding biomarkers for appropriate patient selection as well as tumor progression are necessary for implementation of immunotherapy for GBM.

Central Nervous System Lymphoma in a Patient with Chronic Lymphocytic Leukemia: A Case Report and Literature Review

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia that affects older adults in the Western world. Symptomatic nervous system invasion in undiagnosed CLL is rare, poorly understood, challenging to treat, and associated with decreased survival. The average survival of CLL patients with central nervous system (CNS) involvement is 3.79 years as compared to six years in CLL patients without CNS involvement. Autopsy studies demonstrated a high incidence of undiagnosed CLL with CNS involvement, suggesting that CNS involvement is either underdiagnosed or subclinical. Although the most common site of CNS involvement is the leptomeninges, our case demonstrates an extremely rare form of CNS diffuse large B-cell parenchymal involvement in a patient with a concurrent diagnosis of systemic CLL.

Developing a standardized process for oral chemotherapy management for neuro-oncology

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Background: Oral chemotherapies (OC) have transformed cancer care for millions of patients. While this has improved the patient experience, it presents significant challenges to safety of prescription, administration and side effect monitoring. While there are guidelines for documentation, there is not a best practices system for managing OC. This project identified areas of latent errors and implemented a standardized process for OC management. Methods: After review of the literature, we developed a process map for OC prescriptions at our institution. We then compared processes at three other neuro oncology clinics. We completed a hazard analysis and implemented several changes (see table). We identified binary measures in the medical record for every OC prescription that related to the process changes. Chart review of the 6 months prior to process change was used to create a baseline process mean for each variable. These same variables were monitored every 2 weeks after process change implementation using run charts. Successful process shift was defined as 7 consecutive 2-week averages that were continually on one side of the baseline process mean. Results: 5 months after process change was implemented, we had successfully reduced refills for OC and increased documentation of dose and dose calculation. There is a trend towards improvement in independently verified dose calculation and dedicated chemotherapy teaching visits, however these have not yet reached criteria for process change. Conclusions: This project used published studies, multi-institutional process mapping and hazard analysis to develop and implement a standardize process for OC. This process can be implemented for OC management in other oncology practices. [Table: see text]

Osimertinib for EGFR-Mutant Lung Cancer with Brain Metastases: Results from a Single-Center Retrospective Study

INTRODUCTION

Osimertinib is a third-generation tyrosine kinase inhibitor, initially approved for epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC) with T790M acquired resistance, and now approved in the first-line setting. However, data supporting the use of osimertinib in untreated brain metastases are limited, although it has established central nervous system (CNS) activity. Our study compares the clinical outcomes of patients experiencing progressing brain metastases treated with cranial irradiation and osimertinib with those treated with osimertinib alone.

METHODS

Forty patients who were treated with osimertinib at the Stanford Cancer Center from November 2015 to December 2016 were identified by searching an electronic medical record database. Eleven patients had progressing brain metastases and did not receive radiation (group A), 9 patients had progressing brain metastases and received radiation when starting osimertinib (group B), and 20 patients had stable brain metastases at the time of initiating osimertinib (group C). Patient and disease characteristics, radiographic responses, and survival outcomes were evaluated retrospectively for the three groups.

RESULTS

The CNS response rate was 32.3%. Median time to treatment failure (TTF), overall progression-free survival (PFS), and overall survival (OS) were 10.0 months (95% confidence interval [CI], 4.5-11.8), 8.8 months (95% CI, 6.2-12.1), and 16.2 months, respectively. Median TTF was 15.1 months for group A (95% CI, 1.7-28.5), 7.7 months for group B (95% CI, 0-15.5), and 10.7 months for group C (95% CI, 9.0-12.5). The median PFS was 8.8 months for group A (95% CI, 4.3-13.4), not reached for group B, and 8.4 months for group C (95% CI, 5.6-11.1). The median OS was not reached for group A and C, and was 16.2 months for group B. There was no apparent difference in TTF, PFS, or OS between the three groups.

CONCLUSION

Receiving radiation prior to starting osimertinib for patients with progressing brain metastases did not prolong TTF, PFS, or OS in our series. To minimize the risks of radiation-related toxicity, delaying radiation could be considered for some patients with EGFR-mutant NSCLC with brain metastases who initially respond to osimertinib in the second-line setting.

IMPLICATIONS FOR PRACTICE

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor recently approved for the first-line treatment of EGFR-mutant non-small cell lung cancer. Although it appears to have central nervous system (CNS) activity, most clinical trials have excluded patients with untreated, progressing brain metastases. This study included patients with stable and progressing CNS metastases treated with osimertinib and found no apparent differences in median time to treatment failure, time to progression, and overall survival in patients who received osimertinib alone compared with those who received osimertinib and radiosurgery. This may support a clinician's decision to defer radiation for selected patients with untreated brain metastases who are candidates for osimertinib therapy.

NCCN Guidelines Insights: Central Nervous System Cancers, Version 1.2017

For many years, the diagnosis and classification of gliomas have been based on histology. Although studies including large populations of patients demonstrated the prognostic value of histologic phenotype, variability in outcomes within histologic groups limited the utility of this system. Nonetheless, histology was the only proven and widely accessible tool available at the time, thus it was used for clinical trial entry criteria, and therefore determined the recommended treatment options. Research to identify molecular changes that underlie glioma progression has led to the discovery of molecular features that have greater diagnostic and prognostic value than histology. Analyses of these molecular markers across populations from randomized clinical trials have shown that some of these markers are also predictive of response to specific types of treatment, which has prompted significant changes to the recommended treatment options for grade III (anaplastic) gliomas.

Abstract 873: BPM 31510, a clinical stage metabolic modulator, demonstrates therapeutic efficacy in glioblastoma models of temozolomide chemo-sensitive and resistance by targeting mitochondrial function

BPM31510 is a metabolic modulating agent composed of a parenteral nanodispersion of ubidecarenone which is currently in clinical studies for glioblastoma. Glioblastoma is a highly metabolic and aggressive malignancy with limited treatment options and dismal median survival. Temozolomide (TMZ) as a first line treatment option, however, 90% of recurrent gliomas acquire TMZ chemoresistance. Recently, acquisition to TMZ resistance has been correlated to alterations in mitochondrial metabolism. Thus, in the present study we sought to investigate whether BPM31510 could elicit anti-cancer activity in TMZ naïve and TMZ-chemoresistant glioma models. In vitro, in a 2D model BPM31510 treatment demonstrated anti-cancer activity in a panel of glioma cell lines (rat C6 and human U251-MG and U87-MG), and this effect was translatable in spheroidal 3D cultures. Importantly, in an aggressive rat C6 orthotopic glioma model, treatment with BPM31510 (50mg/kg/day, b.i.d) starting between 4 and 8 days post-implantation resulted in a 32% cure rate compared to 0% in controls (P &lt; 0.001, Fisher's exact test), demonstrating an improved survival (P &lt; 0.01, log rank survival), despite producing a minimal change in median survival (13 vs. 12 days). A marked increase in caspase3 staining was observed in tumors from BPM31510 treated animals compared to controls assessed at a similar time point post-tumor implantation, suggesting a strong apoptotic effect of this agent in vivo. Next, BPM31510 was examined in a cellular model of acquired TMZ resistance (TMZ-R) generated by exposing parental (chemosensitive naïve) U251-MG and U87-MG cells to increasing concentrations of TMZ for 9-12 months. Similar to parental cells, BPM31510 displayed anti-cancer activity in both TMZ-R cell models, as decreased cell viability and an increase in the percentage of apoptotic cells was observed upon BPM31510 treatment. Consistent with prior studies, compared to parental cells, TMZ-R cells demonstrated metabolic rewiring characterized by increases in mitochondrial function parameters and decreased extracellular acidification rate, indicative of glycolytic flux. Regardless of chemosensitivity, BPM31510 decreased mitochondrial substrate oxidation (e.g., succinate, glycerol-3-phosphate) at doses which induce cell death. Concomitantly, increases in the reactive oxygen species production were observed with BPM 31510 treatment in both parental and TMZ-R cell lines. Together, these data define a link between regulation of mitochondrial function and the anti-cancer activity of BPM31510 in both TMZ chemo-sensitive and resistant glioblastoma models, demonstrating a distinct approach in targeting mitochondrial metabolism for the treatment of this clinically intractable disease.

Citation Format: Tulin Dadali, Shreya Kulkarni, Ryan Ng, Pallavi Awate, Saie Mogre, Anne R. Diers, Taichang Jang, Milton Merchant, Jiaxin Sun, Stephane Gesta, Khampaseuth Thapa, Seema Nagpal, Lawrence Recht, Niven R. Narain, Rangaprasad Sarangarajan. BPM 31510, a clinical stage metabolic modulator, demonstrates therapeutic efficacy in glioblastoma models of temozolomide chemo-sensitive and resistance by targeting mitochondrial function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 873.

Stereotactic Radiosurgery and Hypofractionated Radiotherapy for Glioblastoma

Glioblastoma is the most common primary brain tumor in adults. Standard therapy depends on patient age and performance status but principally involves surgical resection followed by a 6-wk course of radiation therapy given concurrently with temozolomide chemotherapy. Despite such treatment, prognosis remains poor, with a median survival of 16 mo. Challenges in achieving local control, maintaining quality of life, and limiting toxicity plague treatment strategies for this disease. Radiotherapy dose intensification through hypofractionation and stereotactic radiosurgery is a promising strategy that has been explored to meet these challenges. We review the use of hypofractionated radiotherapy and stereotactic radiosurgery for patients with newly diagnosed and recurrent glioblastoma.