Phase II study of border zone stereotactic radiosurgery with bevacizumab in patients with recurrent or progressive glioblastoma multiforme.

PURPOSE: Recurrent glioblastoma is universally fatal with limited effective treatment options. The aim of this phase 2 study of Border Zone SRS plus bevacizumab was to evaluate OS in patients with recurrent GBM. METHODS: Patients with histologically confirmed GBM with recurrent disease who had received prior first-line treatment with fractionated radiotherapy and chemotherapy and eligible for SRS were enrolled. Bevacizumab 10 mg/kg was given day -1, day 14, and then every 14 days until disease progression. 1-14 days before BZ-SRS procedure, patients underwent brain MRI /MRS. MRS with measurement of choline-to-N-acetyl aspartate index (CNI) area ≥ 3 was targeted for SRS. RESULTS: From 2015-2017, sixteen of planned 40 patients were enrolled. The median age was 62 (range, 48-74Y). 3/16 (0.188) participants experienced grade 2 toxicity. No AREs were reported. The mOS was 11.73 months compared to 8.74 months (P = 0.324) from date of SRS for the BZ-SRS and institutional historical controls, respectively. PFS-6 and OS-6 were 31.2% (p = 0.00294) and 81.2%(p = 0.058), respectively. Of 13 evaluable for best response: 1 CR (p = 0.077), 4 PR (p = 0.308), 7 SD (p = 0.538), and 1 PD (p = 0.077). 11/16 participants had MRS scans with an estimated probability that MRS changes a treatment plan of 0 (0, 0.285). CONCLUSION: BZ-SRS with bevacizumab was feasible and well tolerated. There is no significant survival benefit using BZ-SRS with bevacizumab compared to institutional historical controls. Secondary analysis revealed a trend toward improved PFS-6, but not OS-6 after BZ-SRS. MRS scans did not result in changes to SRS treatment plans.

A multi-site phase I trial of Veliparib with standard radiation and temozolomide in patients with newly diagnosed glioblastoma multiforme (GBM).

PURPOSE: A multi-site Phase I trial was conducted to determine the safety, maximum tolerated dose, and pharmacokinetics (PK) of Veliparib, a Poly (ADP-ribose) polymerase [PARP] enzyme inhibitor, when administered with temozolomide (TMZ) alone and then with temozolomide and radiation (RT) in patients with newly diagnosed glioblastoma. METHODS: Given the potential for myelosuppression when a PARP inhibitor is combined with chemotherapy, the first 6 patients accrued were given Veliparib 10 mg bid and TMZ 75 mg/m2/d daily for six weeks. If this was well tolerated, the same doses of Veliparib and TMZ would be tested along with standard radiation with plans to dose escalate the Veliparib in subsequent patient cohorts. Once a maximal tolerated dose was determined, a 78 patient phase II study was planned. Peripheral blood pharmacokinetics were assessed. RESULTS: Twenty-four patients were enrolled. In the first 6 patients who received 6 weeks of TMZ with Veliparib only one dose limiting toxicity (DLT) occurred. The next 12 patients received 6 weeks of RT + TMZ + veliparib and 4/12 (33%) had dose limiting hematologic toxicities. As a result, Veliparib was reduced by 50% to 10 mg BID every other week, but again 3/3 patients had dose limiting hematologic toxicities. The trial was then terminated. The mean clearance (± SD) CL/F of Veliparib for the initial dose (27.0 ± 9.0 L/h, n = 16) and at steady-state for 10 mg BID (23.5 ± 10.4 L/h, n = 18) were similar. Accumulation for BID dosing was 56% (± 33%). CONCLUSIONS: Although Veliparib 10 mg BID administered with TMZ 75 mg/m2 for six weeks was well tolerated, when this regimen was combined with standard partial brain irradiation it was severely myelosuppressive even when the dose was reduced by 50%. This study again highlights the potential of localized cranial radiotherapy to significantly increase hematologic toxicity of marginally myelosuppressive systemic therapies.

Activity of a first-in-class oral HIF2-alpha inhibitor, PT2385, in patients with first recurrence of glioblastoma.

INTRODUCTION: Hypoxia inducible factor 2-alpha (HIF2α) mediates cellular responses to hypoxia and is over-expressed in glioblastoma (GBM). PT2385 is an oral HIF2α inhibitor with in vivo activity against GBM. METHODS: A two-stage single-arm open-label phase II study of adults with GBM at first recurrence following chemoradiation with measurable disease was conducted through the Adult Brain Tumor Consortium. PT2385 was administered at the phase II dose (800 mg b.i.d.). The primary outcome was objective radiographic response (ORR = complete response + partial response, CR + PR); secondary outcomes were safety, overall survival (OS), and progression free survival (PFS). Exploratory objectives included pharmacokinetics (day 15 Cmin), pharmacodynamics (erythropoietin, vascular endothelial growth factor), and pH-weighted amine- chemical exchange saturation transfer (CEST) MRI to quantify tumor acidity at baseline and explore associations with drug response. Stage 1 enrolled 24 patients with early stoppage for ≤ 1 ORR. RESULTS: Of the 24 enrolled patients, median age was 62.1 (38.7-76.7) years, median KPS 80, MGMT promoter was methylated in 46% of tumors. PT2385 was well tolerated. Grade ≥ 3 drug-related adverse events were hypoxia (n = 2), hyponatremia (2), lymphopenia (1), anemia (1), and hyperglycemia (1). No objective radiographic responses were observed; median PFS was 1.8 months (95% CI 1.6-2.5) and OS was 7.7 months (95% CI 4.9-12.6). Drug exposure varied widely and did not differ by corticosteroid use (p = 0.12), antiepileptics (p = 0.09), or sex (p = 0.37). Patients with high systemic exposure had significantly longer PFS (6.7 vs 1.8 months, p = 0.009). Baseline acidity by pH-weighted CEST MRI correlated significantly with treatment duration (R2 = 0.49, p = 0.017). Non-enhancing infiltrative disease with high acidity gave rise to recurrence. CONCLUSIONS: PT2385 monotherapy had limited activity in first recurrent GBM. Drug exposure was variable. Signals of activity were observed in GBM patients with high systemic exposure and acidic lesions on CEST imaging. A second-generation HIF2α inhibitor is being studied.

Fast 3D rosette spectroscopic imaging of neocortical abnormalities at 3 T: Assessment of spectral quality.

PURPOSE: To use a fast 3D rosette spectroscopic imaging acquisition to quantitatively evaluate how spectral quality influences detection of the endogenous variation of gray and white matter metabolite differences in controls, and demonstrate how rosette spectroscopic imaging can detect metabolic dysfunction in patients with neocortical abnormalities. METHODS: Data were acquired on a 3T MR scanner and 32-channel head coil, with rosette spectroscopic imaging covering a 4-cm slab of fronto-parietal-temporal lobes. The influence of acquisition parameters and filtering on spectral quality and sensitivity to tissue composition was assessed by LCModel analysis, the Cramer-Rao lower bound, and the standard errors from regression analyses. The optimized protocol was used to generate normative white and gray matter regressions and evaluate three patients with neocortical abnormalities. RESULTS: As a measure of the sensitivity to detect abnormalities, the standard errors of regression for Cr/NAA and Ch/NAA were significantly correlated with the Cramer-Rao lower bound values (R = 0.89 and 0.92, respectively, both with P < 0.001). The rosette acquisition with a duration of 9.6 min, produces a mean Cramer-Rao lower bound (%) over the entire slab of 4.6 ± 2.6 and 5.8 ± 2.3 for NAA and Cr, respectively. This enables a Cr/NAA standard error of 0.08 (i.e., detection sensitivity of 25% for a 50/50 mixed gray and white matter voxel). In healthy controls, the regression of Cr/NAA versus fraction gray matter in the cingulate differs from frontal and parietal regions. CONCLUSIONS: Fast rosette spectroscopic imaging acquisitions with regression analyses are able to identify metabolic differences across 4-cm slabs of the brain centrally and over the cortical periphery with high efficiency, generating results that are consistent with clinical findings. Magn Reson Med 79:2470-2480, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Retrospective study of nivolumab for patients with recurrent high grade gliomas.

INTRODUCTION: Patients with recurrent high-grade gliomas (HGG) have limited treatment options. HGG utilize the PD-1 pathway to evade immune responses. Checkpoint inhibitors have demonstrated safety and clinical activity in patients with recurrent glioblastoma. We explored the efficacy of nivolumab in recurrent HGG with a primary objective of progression free survival (PFS) and overall survival (OS). METHODS: We retrospectively analyzed HGG patients treated with nivolumab in our institution. We included patients with advanced HGG who received nivolumab at their oncologist's decision. Patients received nivolumab 3 mg/kg every 2 weeks until confirmed progression, intolerable toxicity, death, or physician decision. Radiographic assessments were performed every 8 weeks. RESULTS: Between April 2015 and October 2017, 50 HGG patients received nivolumab. 43 patients received nivolumab with bevacizumab. 44 patients were bevacizumab refractory and 7 patients received nivolumab monotherapy. All had received prior radiation and chemotherapy. 39 adverse events (AEs) were noted [most commonly fatigue (16%) and constipation (10%)]. 4 (8%) patients experienced grade 3-4 AEs. 36 (72%) patients experienced stable disease (SD) at the 2-month assessment. Median duration of SD was 4.3 months (5.1 months in the bevacizumab naïve, 3.8 months in the bevacizumab refractory). Median PFS was 4.3 months (95% CI 3.5-5.3); median OS was 6.5 months (95% CI 6.0-8.8). CONCLUSION: Treatment with nivolumab therapy was associated with a manageable safety profile. In a subset of patients, there was disease stabilization in heavily pre-treated recurrent HGG.

Family caregivers' level of mastery predicts survival of patients with glioblastoma: A preliminary report.

BACKGROUND: Glioblastoma multiforme (GBM) is associated with a poor prognosis, and patients rely heavily on family caregivers for physical and emotional support. The capability and mental health of family caregivers may influence their ability to provide care and affect patient outcomes. The objective of the current study was to investigate whether caregivers' anxiety, depressive symptoms, burden, and mastery influenced survival in a sample of patients newly diagnosed with GBM. METHODS: Baseline data from caregiver-patient dyads participating in a longitudinal study funded by the National Institutes of Health were used. Cox regression analyses were performed to determine whether caregiver anxiety (Profile of Mood States-Anxiety), depressive symptoms (Center for Epidemiologic Studies-Depression Scale), burden (Caregiver Reaction Assessment), and feelings of mastery (Mastery Scale) predicted the survival time of patients with GBM after controlling for known covariates (patient age, Karnofsky performance status, type of surgery, and postsurgical treatment). RESULTS: A total of 88 caregiver-patient dyads were included. The median overall survival for the sample was 14.5 months (range, 0-88 months). After controlling for covariates, caregiver mastery was found to be predictive of patient survival. With each unit increase in mastery, there was a 16.1% risk reduction in patient death (95% confidence interval, 0.771-0.913; P<.001). CONCLUSIONS: To the authors' knowledge, the results of the current study are among the first to explore the impact of family caregiving on the outcomes of patients with GBM. If these results are supported in other studies, providing neuro-oncology caregivers with more structured support and guidance in clinical practice has the potential to improve caregivers' feelings of mastery, thereby influencing patients' well-being for the better. Cancer 2017;123:832-40. © 2016 American Cancer Society.

Neuro-oncology family caregivers' view on keeping track of care issues using eHealth systems: it's a question of time.

Primary brain tumors (PBTs) are rare but have a great impact on both patient and family caregiver wellbeing. Supporting caregivers can help them to continue their caregiving activities to maintain the patients' best possible level of quality of life. Efforts to improve PBT caregiver wellbeing should take into account country- or culture-specific differences in care issues and supportive care needs to serve larger caregiver groups. We aimed to explore PBT caregivers' satisfaction with the current supportive care provision, as well as their thoughts on monitoring their care issues with both paper-based and digital instruments. Twelve PBT caregivers were interviewed in the United States. The semi-structured interviews were transcribed verbatim and analyzed by two coders independently. Data were combined with those collected in the Netherlands, following similar methodology (N = 15). We found that PBT caregivers utilize both formal and informal support services, but that those who experience more care issues would prefer more support, particularly in the early disease phase. Keeping track of care issues was thought to provide more insight into unmet needs and help them find professional help, but it requires investment of time and takes discipline. Caregivers preferred a brief and easy-to-use 'blended care' instrument that combines digital monitoring with personal feedback. The present study shows that the preferences of family caregivers in neuro-oncology toward keeping track of care issues are likely not heavily influenced by country- or culture-specific differences. The development of any instrument thus has the potential to benefit a large group of family caregivers.

Phase I trial of aflibercept (VEGF trap) with radiation therapy and concomitant and adjuvant temozolomide in patients with high-grade gliomas.

Anti-vascular endothelial growth factor (VEGF) therapy has shown promise in the treatment of high-grade gliomas (HGG). Aflibercept is a recombinant human fusion protein that acts as a soluble decoy receptor for VEGF-A, VEGF-B and placental growth factor, depleting circulating levels of these growth factors. The Adult Brain Tumor Consortium conducted a phase I trial of aflibercept and temozolomide (TMZ) in patients with newly diagnosed HGG with 2 dose levels and a 3+3 design. Three arms using aflibercept were examined; with radiation and concomitant temozolomide; with adjuvant temozolomide using the 5/28 regimen; and with adjuvant temozolomide using the 21/28 day regimen. Fifty-nine patients were enrolled, 21 in arm 1, 20 in arm 2 and 18 in arm 3. Median age was 56 years (24-69); median KPS 90 (60-100). The maximum tolerated dose (MTD) of aflibercept for all 3 arms was 4 mg/kg every 2 weeks. Dose limiting toxicities at the MTD were: Arm 1: 0/21 patients; Arm 2: 2/20 patients (G3 deep vein thrombosis, G4 neutropenia; Arm 3: 3/18 patients) (G4 biopsy-confirmed thrombotic microangiopathy, G3 rash, G4 thrombocytopenia). The median number of cycles of aflibercept was 5 (range, 1-16). All patients stopped treatment; 28 (47%) for disease progression, 21 (36%) for toxicities, 8 (14%) for other reasons, and 2 (3%) patients completed the full treatment course. This study met its primary endpoint and the MTD of aflibercept with radiation and concomitant and adjuvant temozolomide is 4 mg/kg every 2 weeks.

Effect of Tumor-Treating Fields Plus Maintenance Temozolomide vs Maintenance Temozolomide Alone on Survival in Patients With Glioblastoma: A Randomized Clinical Trial.

Importance: Tumor-treating fields (TTFields) is an antimitotic treatment modality that interferes with glioblastoma cell division and organelle assembly by delivering low-intensity alternating electric fields to the tumor. Objective: To investigate whether TTFields improves progression-free and overall survival of patients with glioblastoma, a fatal disease that commonly recurs at the initial tumor site or in the central nervous system. Design, Setting, and Participants: In this randomized, open-label trial, 695 patients with glioblastoma whose tumor was resected or biopsied and had completed concomitant radiochemotherapy (median time from diagnosis to randomization, 3.8 months) were enrolled at 83 centers (July 2009-2014) and followed up through December 2016. A preliminary report from this trial was published in 2015; this report describes the final analysis. Interventions: Patients were randomized 2:1 to TTFields plus maintenance temozolomide chemotherapy (n = 466) or temozolomide alone (n = 229). The TTFields, consisting of low-intensity, 200 kHz frequency, alternating electric fields, was delivered (≥ 18 hours/d) via 4 transducer arrays on the shaved scalp and connected to a portable device. Temozolomide was administered to both groups (150-200 mg/m2) for 5 days per 28-day cycle (6-12 cycles). Main Outcomes and Measures: Progression-free survival (tested at α = .046). The secondary end point was overall survival (tested hierarchically at α = .048). Analyses were performed for the intent-to-treat population. Adverse events were compared by group. Results: Of the 695 randomized patients (median age, 56 years; IQR, 48-63; 473 men [68%]), 637 (92%) completed the trial. Median progression-free survival from randomization was 6.7 months in the TTFields-temozolomide group and 4.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.52-0.76; P < .001). Median overall survival was 20.9 months in the TTFields-temozolomide group vs 16.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.53-0.76; P < .001). Systemic adverse event frequency was 48% in the TTFields-temozolomide group and 44% in the temozolomide-alone group. Mild to moderate skin toxicity underneath the transducer arrays occurred in 52% of patients who received TTFields-temozolomide vs no patients who received temozolomide alone. Conclusions and Relevance: In the final analysis of this randomized clinical trial of patients with glioblastoma who had received standard radiochemotherapy, the addition of TTFields to maintenance temozolomide chemotherapy vs maintenance temozolomide alone, resulted in statistically significant improvement in progression-free survival and overall survival. These results are consistent with the previous interim analysis. Trial Registration: clinicaltrials.gov Identifier: NCT00916409.

A randomized phase I/II study of ABT-888 in combination with temozolomide in recurrent temozolomide resistant glioblastoma: an NRG oncology RTOG group study.

This study tested the hypothesis that ABT-888 (velparib), a poly (ADP-ribose) polymerase (PARP) inhibitor, can modulate temozolomide (TMZ) resistance in recurrent TMZ refractory glioblastoma patients. The combination regimen (TMZ/ABT-888) was tested using two randomized schedules (5 vs. 21 days), with 6-month progression free survival (PFS6) as the primary endpoint. The maximum tolerated dose (MTD) for TMZ using the 21 day of 28 TMZ schedule, in concert with 40 mg BID ABT-888 was determined in a phase I portion of this study, and previously reported to be 75 mg/m(2) (arm1). The MTD for ABT-888 (40 mg BID) and the 5 of 28 day TMZ (150-200 mg/m(2)) schedule was known from prior trials (arm2). Two cohorts were studied: bevacizumab (BEV) naïve (n = 151), and BEV refractory (n = 74). Overall ten patients were ineligible. The incidence rate of grade 3/4 myelosuppression over all was 20.0 %. For the BEV refractory cohort, the PFS 6 was 4.4 %; for the BEV naïve cohort, PFS6 was 17 %. Overall survival was similar for both arms in both the BEV naïve [median survival time (MST) 10.3 M; 95 % CI 8.4-12] and BEV refractory cohort (MST 4.7 M; 95 %CI 3.5-5.6). The median PFS was essentially the same for both arms and both cohorts at ~2.0 M (95 % CI 1.9-2.1).

Short-T2 imaging for quantifying concentration of sodium (23 Na) of bi-exponential T2 relaxation.

PURPOSE: This work intends to demonstrate a new method for quantifying concentration of sodium (23 Na) of bi-exponential T2 relaxation in patients on MRI scanners at 3.0 Tesla. THEORY AND METHODS: Two single-quantum (SQ) sodium images acquired at very-short and short echo times (TE = 0.5 and 5.0 ms) are subtracted to produce an image of the short-T2 component of the bi-exponential (or bound) sodium. An integrated calibration on the SQ and short-T2 images quantifies both total and bound sodium concentrations. Numerical models were used to evaluate signal response of the proposed method to the short-T2 components. MRI scans on agar phantoms and brain tumor patients were performed to assess accuracy and performance of the proposed method, in comparison with a conventional method of triple-quantum filtering. RESULTS: A good linear relation (R2 = 0.98) was attained between the short-T2 image intensity and concentration of bound sodium. A reduced total scan time of 22 min was achieved under the SAR restriction for human studies in quantifying both total and bound sodium concentrations. CONCLUSION: The proposed method is feasible for quantifying bound sodium concentration in routine clinical settings at 3.0 Tesla. Magn Reson Med 74:162-174, 2015. © 2014 Wiley Periodicals, Inc.

Maintenance Therapy With Tumor-Treating Fields Plus Temozolomide vs Temozolomide Alone for Glioblastoma: A Randomized Clinical Trial.

IMPORTANCE: Glioblastoma is the most devastating primary malignancy of the central nervous system in adults. Most patients die within 1 to 2 years of diagnosis. Tumor-treating fields (TTFields) are a locoregionally delivered antimitotic treatment that interferes with cell division and organelle assembly. OBJECTIVE: To evaluate the efficacy and safety of TTFields used in combination with temozolomide maintenance treatment after chemoradiation therapy for patients with glioblastoma. DESIGN, SETTING, AND PARTICIPANTS: After completion of chemoradiotherapy, patients with glioblastoma were randomized (2:1) to receive maintenance treatment with either TTFields plus temozolomide (n = 466) or temozolomide alone (n = 229) (median time from diagnosis to randomization, 3.8 months in both groups). The study enrolled 695 of the planned 700 patients between July 2009 and November 2014 at 83 centers in the United States, Canada, Europe, Israel, and South Korea. The trial was terminated based on the results of this planned interim analysis. INTERVENTIONS: Treatment with TTFields was delivered continuously (>18 hours/day) via 4 transducer arrays placed on the shaved scalp and connected to a portable medical device. Temozolomide (150-200 mg/m2/d) was given for 5 days of each 28-day cycle. MAIN OUTCOMES AND MEASURES: The primary end point was progression-free survival in the intent-to-treat population (significance threshold of .01) with overall survival in the per-protocol population (n = 280) as a powered secondary end point (significance threshold of .006). This prespecified interim analysis was to be conducted on the first 315 patients after at least 18 months of follow-up. RESULTS: The interim analysis included 210 patients randomized to TTFields plus temozolomide and 105 randomized to temozolomide alone, and was conducted at a median follow-up of 38 months (range, 18-60 months). Median progression-free survival in the intent-to-treat population was 7.1 months (95% CI, 5.9-8.2 months) in the TTFields plus temozolomide group and 4.0 months (95% CI, 3.3-5.2 months) in the temozolomide alone group (hazard ratio [HR], 0.62 [98.7% CI, 0.43-0.89]; P = .001). Median overall survival in the per-protocol population was 20.5 months (95% CI, 16.7-25.0 months) in the TTFields plus temozolomide group (n = 196) and 15.6 months (95% CI, 13.3-19.1 months) in the temozolomide alone group (n = 84) (HR, 0.64 [99.4% CI, 0.42-0.98]; P = .004). CONCLUSIONS AND RELEVANCE: In this interim analysis of 315 patients with glioblastoma who had completed standard chemoradiation therapy, adding TTFields to maintenance temozolomide chemotherapy significantly prolonged progression-free and overall survival. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00916409.

A multicenter, phase 1, Adult Brain Tumor Consortium trial of oral terameprocol for patients with recurrent high-grade glioma (GATOR).

Recurrent high-grade gliomas (rHGGs) have a dismal prognosis, where the maximum tolerated dose (MTD) of IV terameprocol (5 days/month), a transcriptional inhibitor of specificity protein 1 (Sp1)-regulated proteins, is 1,700 mg/day with median area under the plasma concentration-time curve (AUC) of 31.3 µg∗h/mL. Given potentially increased efficacy with sustained systemic exposure and challenging logistics of daily IV therapy, here we investigate oral terameprocol for rHGGs in a multicenter, phase 1 trial (GATOR). Using a 3 + 3 dose-escalation design, we enroll 20 patients, with median age 60 years (range 31-80), 70% male, and median one relapse (range 1-3). Fasting patients tolerate 1,200 mg/day (n = 3), 2,400 mg/day (n = 6), 3,600 mg/day (n = 3), and 6,000 mg/day (n = 2) oral doses without major toxicities. However, increased dosage does not lead to increased systemic exposure, including in fed state (6,000 mg/day, n = 4), with maximal AUC <5 µg∗h/mL. These findings warrant trials investigating approaches that provide sustained systemic levels of transcription inhibitors to exploit their therapeutic potential. This study was registered at ClinicalTrials.gov (NCT02575794).

An ERK5-PFKFB3 axis regulates glycolysis and represents a therapeutic vulnerability in pediatric diffuse midline glioma.

Metabolic reprogramming in pediatric diffuse midline glioma is driven by gene expression changes induced by the hallmark histone mutation H3K27M, which results in aberrantly permissive activation of oncogenic signaling pathways. Previous studies of diffuse midline glioma with altered H3K27 (DMG-H3K27a) have shown that the RAS pathway, specifically through its downstream kinase, extracellular-signal-related kinase 5 (ERK5), is critical for tumor growth. Further downstream effectors of ERK5 and their role in DMG-H3K27a metabolic reprogramming have not been explored. We establish that ERK5 is a critical regulator of cell proliferation and glycolysis in DMG-H3K27a. We demonstrate that ERK5 mediates glycolysis through activation of transcription factor MEF2A, which subsequently modulates expression of glycolytic enzyme PFKFB3. We show that in vitro and mouse models of DMG-H3K27a are sensitive to the loss of PFKFB3. Multi-targeted drug therapy against the ERK5-PFKFB3 axis, such as with small-molecule inhibitors, may represent a promising therapeutic approach in patients with pediatric diffuse midline glioma.

A Multi-Site Phase I Trial of Veliparib with Standard Radiation and Temozolomide in Patients with Newly Diagnosed Glioblastoma Multiforme (GBM).

Purpose: A multi-site Phase I trial was conducted to determine the safety, maximum tolerated dose, and pharmacokinetics (PK) of Veliparib, a Poly (ADP-ribose) polymerase [PARP] enzyme inhibitor, when administered with temozolomide (TMZ) alone and then with temozolomide and radiation (RT) in patients with newly diagnosed glioblastoma. Methods: Given the potential for myelosuppression when a PARP inhibitor is combined with chemotherapy, the first 6 patients accrued were given Veliparib 10 mg bid and TMZ 75 mg/m2/d daily for six weeks. If this was well tolerated, the same doses of Veliparib and TMZ would be tested along with standard radiation with plans to dose escalate the Veliparib in subsequent patient cohorts. Once a maximal tolerated dose was determined, a 78 patient phase II study was planned. Peripheral blood pharmacokinetics were assessed. Results: Twenty-four patients were enrolled. In the first 6 patients who received 6 weeks of TMZ with Veliparib only one dose limiting toxicity (DLT) occurred. The next 12 patients received 6 weeks of RT + TMZ + veliparib and 4/12 (33%) had dose limiting hematologic toxicities. As a result, Veliparib was reduced by 50% to 10 mg BID every other week, but again 3/3 patients had dose limiting hematologic toxicities. The trial was then terminated. The mean clearance (± SD) CL/F of Veliparib for the initial dose (27.0 ± 9.0 L/h, n = 16) and at steady-state for 10 mg BID (23.5 ± 10.4 L/h, n = 18) were similar. Accumulation for BID dosing was 56% (± 33%). Conclusions: Although Veliparib 10 mg BID administered with TMZ 75 mg/m2 for six weeks was well tolerated, when this regimen was combined with standard partial brain irradiation it was severely myelosuppressive even when the dose was reduced by 50%. This study again highlights the potential of localized cranial radiotherapy to significantly increase hematologic toxicity of marginally myelosuppressive systemic therapies.

Multicenter Phase II Trial of the PARP Inhibitor Olaparib in Recurrent IDH1- and IDH2-mutant Glioma.

Purpose: Isocitrate dehydrogenase (IDH) 1 and IDH2 mutations (IDH1/2mt) are frequent in glioma. Preclinical studies suggest IDH1/2mts confer "BRCAness" phenotype, a vulnerability that can be targeted through PARP inhibition. To test this hypothesis, we conducted a multicenter study of olaparib monotherapy in patients with IDH1/2mt gliomas. Methods: Patients with recurrent, contrast-enhancing IDH1/2mt gliomas were enrolled in a two-step phase II trial; the primary endpoint was overall response rate per Response Assessment in Neuro-Oncology (RANO) criteria. Olaparib 300 mg orally twice daily was given. Results: A total of 15 evaluable patients were enrolled. Histology was astrocytoma (N = 12) and oligodendroglioma (N = 3). Most toxicities were grade 1 or 2. Best response was stable disease (SD) in 9 (60%) patients. Median progression-free survival (PFS) was 3.63 months and median overall survival was 20.7 months. For patients with SD, median PFS was 5.53 months; 4 patients had SD for >6 months. Among patients with best response progressive disease (N = 6), 5 had grade 4 tumor and 4 had known CDKN2A alteration. PFS was 5.23 months for grades 2 or 3 tumors (N = 10) versus 1.8 months for grade 4 (N = 5; P = 0.0013). Conclusion: The study did not meet the prespecified response-based activity threshold for moving to step 2. However, prolonged SD was observed in patients with grades 2 and 3 histologies, suggesting olaparib monotherapy could be of clinical benefit in select populations. Grade 4 tumors per 2021 World Health Organization classification defined by histology or CDKN2A alteration derived no benefit from this drug, highlighting the usefulness of this classification for future patient stratification and trial design. Significance: A single-arm phase II trial of olaparib in IDH-mutant glioma demonstrated clinically significant prolonged SD for select patients with grade 2/3 disease, suggesting potential benefit of olaparib in IDH-mutant gliomas.

Immuno-PET Imaging of CD69 Visualizes T-Cell Activation and Predicts Survival Following Immunotherapy in Murine Glioblastoma.

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. Immunotherapy may be promising for the treatment of some patients with GBM; however, there is a need for noninvasive neuroimaging techniques to predict immunotherapeutic responses. The effectiveness of most immunotherapeutic strategies requires T-cell activation. Therefore, we aimed to evaluate an early marker of T-cell activation, CD69, for its use as an imaging biomarker of response to immunotherapy for GBM. Herein, we performed CD69 immunostaining on human and mouse T cells following in vitro activation and post immune checkpoint inhibitors (ICI) in an orthotopic syngeneic mouse glioma model. CD69 expression on tumor-infiltrating leukocytes was assessed using single-cell RNA sequencing (scRNA-seq) data from patients with recurrent GBM receiving ICI. Radiolabeled CD69 Ab PET/CT imaging (CD69 immuno-PET) was performed on GBM-bearing mice longitudinally to quantify CD69 and its association with survival following immunotherapy. We show CD69 expression is upregulated upon T-cell activation and on tumor-infiltrating lymphocytes (TIL) in response to immunotherapy. Similarly, scRNA-seq data demonstrated elevated CD69 on TILs from patients with ICI-treated recurrent GBM as compared with TILs from control cohorts. CD69 immuno-PET studies showed a significantly higher tracer uptake in the tumors of ICI-treated mice compared with controls. Importantly, we observed a positive correlation between survival and CD69 immuno-PET signals in immunotherapy-treated animals and established a trajectory of T-cell activation by virtue of CD69-immuno-PET measurements. Our study supports the potential use of CD69 immuno-PET as an immunotherapy response assessment imaging tool for patients with GBM. Significance: Immunotherapy may hold promise for the treatment of some patients with GBM. There is a need to assess therapy responsiveness to allow the continuation of effective treatment in responders and to avoid ineffective treatment with potential adverse effects in the nonresponders. We demonstrate that noninvasive PET/CT imaging of CD69 may allow early detection of immunotherapy responsiveness in patients with GBM.

Primary central nervous system post-transplant lymphoproliferative disorders following allogeneic hematopoietic stem cell transplantation.

Post-transplant lymphoproliferative disorder (PTLD) is a serious complication after allogeneic hematopoietic stem cell transplantation (HSCT). Extra nodal involvement is common in PTLD, but isolated involvement of the central nervous system (CNS) is extremely rare. Given the rarity of primary CNS-PTLD there is no consensus on optimal treatment. We report a patient who developed Epstein-Barr virus related primary CNS-PTLD following allogeneic HSCT who was treated with the monoclonal anti-CD20 antibody rituximab and reduction of immunosuppression. In addition, we review the literature and discuss treatment options for patients with primary CNS-PTLD following allogeneic HSCT.

Salvage gamma knife stereotactic radiosurgery followed by bevacizumab for recurrent glioblastoma multiforme: a case-control study.

We evaluated the efficacy and safety of gamma knife stereotactic radiosurgery (GKSR) followed by bevacizumab combined with chemotherapy in 11 patients with recurrent glioblastoma multiforme who experienced tumor progression despite aggressive initial multi-modality treatment. Our experience included eight male and three female patients. The median patient age at GKSR was 62 years (range 46-72 years). At the time of GKSR, seven patients had a first recurrence and four had two or more recurrences. The median interval from the initial diagnosis until GKSR was 17 months (range 5-34.5 months). The median tumor volume was 13.6 cm(3) (range 1.2-45.1 cm(3)) and the median margin dose of GKSR was 16 Gy (range 13-18 Gy). Following GKSR, bevacizumab was administrated with irinotecan in nine patients and with temozolomide in one patient. One patient was treated with bevacizumab monotherapy. The treatment outcomes were compared to 44 case-matched controls who underwent GKSR without additional bevacizumab. At a median of 13.7 months (range 4.6-28.3 months) after radiosurgery, tumor progression was evident in seven patients. The median progression-free survival (PFS) was 15 months (95% confidential interval (CI), 6.5-23.3 months). Six-month and 1-year PFS rates were 73 and 55%, respectively. The median overall survival (OS) from GKSR was 18 months (95% CI, 10.1-25.7 months) and 1-year OS rate was 73%. One patient (9%) experienced grade III toxicity and one patient (9%) had major adverse radiation effects. Compared with patients who did not receive bevacizumab, the patients who received bevacizumab had significantly prolonged PFS (15 months vs. 7 months, P = 0.035) and OS (18 months vs. 12 months, P = 0.005), and were less likely to develop an adverse radiation effect (9 vs. 46%, P = 0.037). The combination of salvage GKSR followed by bevacizumab added potential benefit and little additional risk in a small group of patients with progressive glioblastoma. Further experience is needed to define the efficacy and long-term toxicity with this strategy.

Cilengitide in patients with recurrent glioblastoma: the results of NABTC 03-02, a phase II trial with measures of treatment delivery.

Cilengitide is a cyclic pentapeptide that is a specific inhibitor of the αvß3 and αvß5 integrins. Preclinical studies demonstrate antiangiogenic activity and anti-invasive activity in a number of glioma models. This study was designed to evaluate the efficacy and tumor delivery of cilengitide in patients with recurrent glioblastoma. Patients with recurrent glioblastoma who require a surgical resection for optimal clinical care received 3 intravenous doses of cilengitide at either 500 or 2000 mg (day -8, -4, -1) prior to undergoing tumor resection with corresponding blood samples for plasma to tumor comparisons. After recovery from surgery, patients were treated with cilengitide (2000 mg i.v. twice weekly, maximum of 2 years of treatment). The study accrued 30 patients with recurrent glioblastoma, 26 were evaluable for efficacy. The 6-month progression free survival rate was 12%. Cilengitide was detected in all tumor specimens with higher levels in the group receiving 2000 mg dosing while corresponding plasma concentrations were low, often below the lower limit of detection. These results confirm drug delivery and possibly retention in tumor. This study provides evidence that with established dosing, cilengitide is adequately delivered to the tumor, although as a single agent, efficacy in recurrent glioblastoma is modest. However, these results demonstrating drug delivery to tumor do support continued investigation of this agent as preliminary results from recent studies combining cilengitide with cytotoxic therapies are promising.