bluuebunny/crossref_metadata_2025_split huggingface dataset:
CTIM-17. PHASE I STUDY OF THE SAFETY AND IMMUNOGENICITY OF PERSONALIZED NEOANTIGEN VACCINES AND TUMOR TREATING FIELDS IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA
Authors: Kodysh Julia , Rubinsteyn Alex , Blazquez Ana , Mandeli John , Bhardwaj Nina , Hormigo Adilia 
Published: December 2020

Abstract

BACKGROUND
Glioblastoma (GBM) generates mutation-derived tumor antigens, which arise from somatic variants that result in mutated protein fragments displayed to immune cells. These mutated proteins can provide targets for anti-tumor personalized neoantigen vaccine (PNV) therapy. Combining PNV with Tumor Treating Fields (TTFields), a modality that increases survival of GBM patients, is a viable option.

METHODS
In this phase I study (NCT03223103), PNV and TTFields are combined with the standard treatment for newly diagnosed GBM. Neoantigens are identified using the OpenVax computational pipeline, which identifies somatic variants in a patient’s DNA and ranks resulting neoantigens by their tumor RNA abundance and predicted HLA-I binding affinity. Each patient is vaccinated with up to 10 mutated peptides, receiving 14 doses of PNV administered subcutaneously with poly-ICLC as the adjuvant.

RESULTS
We report our preliminary results in the 8 patients with median age 59 (range 32–84) that have been vaccinated. Neoantigens were identified in each tumor sample in sufficient quantities for vaccination, with each vaccine comprising a median of 8.5 peptides (range 6–10). Patients received a median of 13 vaccines (range 8–14). Immune monitoring for one of the patients showed neoantigen-specific CD4 and CD8 T cell responses. There was radiological tumor progression in two while receiving PNV and in another, prior to PNV. The most common adverse events of the PNV were injection site reaction and flu-like symptoms. Combination with TTFields did not increase toxicity. The Kaplan-Meier estimated 12-month progression-free survival is 62.5% (s.e.= 17.1%) and the estimated 12-month survival from date of surgery is 83.3% (s.e.= 16.7%). The median survival has not been reached.

CONCLUSIONS
Despite a typically low mutational burden of GBM, selection of a sufficient number of neoantigens was successful for each patient’s vaccine. Treatment with PNV and TTFields is safe. The data is encouraging and updated results will be presented.
CTIM-19. MOLECULAR AND GENETIC DETERMINANTS OF RESPONSE TO PD-1 BLOCKADE IN RECURRENT GLIOBLASTOMA PATIENTS
Authors: Prins Robert , Galvez Mildred , Amouzgar Meelad , Campbell Katie , Wells Daniel , Bayless Nicholas , Everson Richard , Cloughesy Timothy 
Published: December 2020

Abstract
Despite immune checkpoint inhibitors having success in several other tumor types, many glioblastoma (GBM) patients fail to respond or maintain a sustained response. Work published by our group (Cloughesy et al, 2019) demonstrated that relative to adjuvant programmed cell death-1 (PD-1) blockade, neoadjuvant treatment doubled the median overall survival (OS) for recurrent GBM patients and resulted in an enhanced interferon-γ signature. This suggests that anti-PD-1 given in the neoadjuvant setting may improve outcomes for recurrent GBM patients. The challenge remains in identifying the molecular and genetic signatures associated with response to immune checkpoint blockade. To address this, we analyzed the tumor sample and clinical response data from the patients treated in this clinical trial (n=31). We stratified patients as stable disease (SD) versus progressive disease (PD) based on their response assessment in neuro-oncology criteria (RANO) scores from cycle 2 of treatment post-surgery. Among the SD patients, 77.8% received neoadjuvant treatment while 22.2% received adjuvant therapy. In this group, a median OS was not reached. Among the PD patients, 40.9% received neoadjuvant treatment and 59.1% received adjuvant therapy, with a median OS of 257 days. Next, we analyzed factors that impact response to immunotherapy, which includes somatic mutational burden and interferon-γ pathway induction. We calculated somatic mutational variants, copy number variants (CNVs), and differential gene expression from the bulk tumor exome and RNA-sequencing data. The total mutation counts were similar between groups and no association was identified with increased mutational burden. In addition, total CNV stability was similar between groups. However, when looking at genes involved in the JAK/STAT signaling pathway, there were notably more copy number losses of JAK2 in the PD group when compared to the SD group (85.0% versus 66.7%). These findings merit further exploration as the JAK/STAT pathway has been implicated in response to immune checkpoint blockade.
CTIM-28. PHASE 2 TRIAL OF CONTROLLED IL-12 IN COMBINATION WITH PD-1 INHIBITOR IN ADULT SUBJECTS WITH RECURRENT GLIOBLASTOMA (rGBM)
Authors: Lukas Rimas , Chiocca E Antonio , Bush Nancy Ann Oberheim , Landolfi Joseph , Cavaliere Robert , Yu John , Kurz Sylvia , Demars Nathan , Buck Jill , Hadar Nira , Miao John , Loewy John , Wang Yunxia , Gelb Arnold , Cooper Laurence 
Published: December 2020

Abstract
Ad-RTS-hIL-12 (Ad) is a gene therapy candidate for intratumoral (IT) delivery that conditionally expresses IL-12 (IL-12) under the transcriptional control of orally administered veledimex (V) acting via the RheoSwitch Therapeutic Systemâ gene switch. Increased PD-1 expression in samples of rGBM following Ad+V (ASCO 2020) supports combination immunotherapy with a PD-1 inhibitor. Phase 1 trials in rGBM of Ad+V as monotherapy and in combination with PD-1 inhibitor revealed encouraging safety and survival data. This phase 2 trial (NCT04006119) in adults with rGBM is evaluating safety and efficacy (overall survival) of Ad + V with pre/post-operative cemiplimab-rwlc (cemi) 350 mg IV, Days -7, 15, then Q3W; Ad single IT injection (2 x 1011 viral particles, day of resection (Day 0) /craniotomy); and V (20 mg PO, Days 0–14). Longitudinal sampling of serum assessed IL-12 and endogenous cytokines production. Anti-tumor effects were described upon preliminary review. Serial MRI evaluated tumor response. Follow-up described overall survival. Initial safety data (51 unique adverse reactions in 28 subjects) appeared similar to Ad+V and the cemi label, respectively, being manageable without synergistic toxicities and generally reversible. Of 35 SAEs reported in 18 subjects, 10 SAEs in 7 subjects were related to Ad+V. IL-12 and IFN-g levels increased after Ad+V administration peaking on Day 3 at 34 ± 11 pg/mL and 13 ± 5 pg/mL (mean ± SEM), respectively. Immune-mediated anti-tumor effects were noted, including a post-treatment biopsy to rule out progression which demonstrated an immune infiltrate consistent with pseudoprogression and loss of tumor cell heterogeneity suggesting immunoediting. Enrollment is anticipated to be completed in 2Q2020 with follow-up ongoing and initial survival data will be presented. V crossed the blood-brain barrier to produce functional IL-12. Controlled IL-12 therapy and cemi is a rational combination with initial data consistent with immune-mediated anti-tumor effects with a favorable safety profile.
CTIM-32. PHASE II AND BIOMARKER STUDY OF PEMBROLIZUMAB OR PEMBROLIZUMAB PLUS BEVACIZUMAB FOR RECURRENT GLIOBLASTOMA PATIENTS
Authors: Reardon David , Molinaro Annette , Peters Katherine , Clarke Jennifer , Jordan Justin , de Groot John , Nghiemphu Phioanh , Kaley Thomas , Colman Howard , McCluskey Christine , Smith Timothy , Cote David , Severgnini Mariano , Yearley Jennifer , Zhao Qing , Blumenschein Wendy , Duda Gabriel , Muzikansky Alona , Jain Rakesh , Wen Patrick , Nayak Lakshmi 
Published: December 2020

Abstract

PURPOSE
Vascular endothelial growth factor (VEGF) is upregulated in glioblastoma and may contribute to immunosuppression. We performed a phase 2 study of pembrolizumab, a programmed death-1 (PD-1) blocking antibody alone or with the anti-VEGF antibody bevacizumab in recurrent glioblastoma with detailed analyses of biomarkers and patient neurologic function.

METHODS
Eighty bevacizumab-naive, recurrent glioblastoma patients were randomized to receive pembrolizumab with bevacizumab (cohort A, n=50) or pembrolizumab monotherapy (cohort B, n=30). The primary endpoint was six-month progression-free survival (PFS-6). Exploratory endpoints included evaluation of tumor PD-L1 expression, TIL density, immune activation gene expression signature and plasma cytokines with outcome. Changes in neurologic function were prospectively assessed using the Neurologic Assessment in Neuro-Oncology (NANO) scale.

RESULTS
Pembrolizumab alone or with bevacizumab was well tolerated but of limited benefit. For cohort A, PFS-6 was 26.0% (95% CI: 16.3, 41.5), median OS was 8.8 months (95% CI: 7.7, 14.2), ORR was 20% and median duration of response was 48 weeks. For cohort B, PFS-6 was 6.7% (95% CI: 1.7, 25.4), median OS was 10.3 months (95% CI: 8.5, 12.5) and ORR was 0%. Factors associated with worsened OS included baseline dexamethasone use and increased post-therapy plasma VEGF (cohort A) and wild-type IDH1, unmethylated MGMT and increased baseline PlGF and sVEGFR1 levels (cohort B), but tumor immune markers were not informative. The NANO scale effectively predicted neurologic function.

CONCLUSIONS
Although well tolerated, pembrolizumab was ineffective both as monotherapy and with bevacizumab for recurrent glioblastoma. Nonetheless, radiographic responses to combinatorial therapy were durable. Baseline dexamethasone use and plasma cytokines but not tumor immunologic biomarkers were associated with outcome. Neurologic function evaluated by the NANO scale contributed to outcome assessment.
CTNI-01. EFFECT OF STEREOTACTIC RADIOSURGERY COMPARED TO WHOLE-BRAIN RADIOTHERAPY FOR LIMITED BRAIN METASTASIS ON LONG TERM COGNITION AND QUALITY OF LIFE: A POOLED ANALYSIS OF RANDOMIZED CLINICAL TRIALS
Authors: Palmer Joshua , Klamer Brett , Ballman Karla , Brown Paul , Cerhan Jane , Anderson S Keith , Whitton Anthony , Greenspoon Jeffrey , Chung Caroline , Burri Stuart , Parney Ian , Stieber Volker , Pollock Bruce , Laack Nadia , Ashman Jonathon , Bahary Jean-Paul , Barker Fred , Galanis Evanthia , Asher Anthony , Roberge David 
Published: December 2020

Abstract

PURPOSE
We investigated the long term impact of SRS and WBRT in two large prospective phase III trials.

METHODS
Patients with 1–4 BMs +/- resection were randomized to SRS or WBRT. Cognitive deterioration was a drop of &gt;1 standard deviation from baseline in &gt;2/6 cognitive measures (CM). Quality of life (QOL) scores were scored 0–100 point scale. CM and QOL scores were modeled using baseline adjusted Linear Mixed Models (LMM) with uncorrelated random intercept for subject and random slopes for time. Differences over time between groups and the effect of &gt;2 cognitive scores with &gt;2 SD change from baseline were assessed.

RESULTS
88 patients were included with median follow up of 24 months. We observed decreasing CM over time (SRS: 4/6; WBRT: 5/6). Mean CM was significantly higher in SRS for Total recall and Delayed Recall at 3, 6, 9, 12 months. More patients in WBRT arm declined 1 SD in &gt;1 and &gt;2 CM at the 3, 6, 9, and 12 months. A 1 SD decline in &gt;3 CM at 1 year was 21% SRS vs 47% WBRT (p=0.02). SRS had fewer patients with a 2 SD decline in &gt;1 CM at every time point. SRS had fewer patients with a 2 SD decline at &gt;2 and &gt;3 CM. WBRT had lower QOL at 3 months, but switched to SRS having lower QOL at 24 months for PWB, EWB, FWB, FactG, BR, and FactBR (p&lt; 0.05). A 2 SD decline in cognition decreased mean FWB by 6.4 units (95% CI: -11, -1.75; p=0.007) and decreased QOL by 5.1 units (95% CI: -7.7, -2.5; p&lt; 0.001).

CONCLUSIONS
We report the first pooled prospective study demonstrating the long term outcomes of patients with BMs after cranial radiation. WBRT was associated with worse cognitive outcomes. Impaired cognition is associated with worse QOL.
CTNI-09. A PHASE I HEALTHY VOLUNTEER STUDY ON THE RELATIVE BIOAVAILABILITY AND FOOD EFFECT OF CAPSULE AND GRANULE FORMULATIONS OF SELUMETINIB
Authors: Cohen-Rabbie Sarit , Mattinson Alexandra , So Karen , Wang Nan , McBride Eileen , Vishwanathan Karthick , Goldwater Ronald 
Published: December 2020

Abstract
Selumetinib (AZD6244, ARRY-142886) is an oral, potent and highly selective allosteric MEK 1/2 inhibitor approved by the FDA as a capsule formulation for treatment of pediatric patients ≥ 2 years old with neurofibromatosis type 1 and symptomatic, inoperable plexiform neurofibromas. A new granule formulation is being developed to support dose flexibility and for patients unable to swallow capsules. This Phase I, open-label, single-center, randomized crossover pharmacokinetics study (NCT03649165) investigated the new granule versus capsule formulation in both fasted and fed (low-fat) states. Twenty-four healthy adult male volunteers were randomized to receive single-dose selumetinib in one of four treatment sequences: 25 mg granule (fasted); 50 mg capsule (fasted); 25 mg granule (fed); and 50 mg capsule (fed). Primary endpoint: to compare pharmacokinetics of the formulations in fasted state. Secondary endpoints: pharmacokinetics of the formulations in fasted versus fed states, granule palatability, safety and tolerability. In fasted state, a slight delay in absorption of selumetinib by ~0.60 h, with geometric mean ratios (90% CI) of 0.65 (0.58, 0.74) for Cmax/dose and 0.87 (0.81, 0.92) for AUC/dose, was detected when administered as granule versus capsule. For granule in fed versus fasted states, geometric mean Cmax and AUC ratios (90% CI) were 0.61 (0.51, 0.72) and 0.97 (0.91, 1.02). For capsule in fed versus fasted states, geometric mean Cmax and AUC ratios (90% CI) were 0.40 (0.33, 0.48) and 0.62 (0.55, 0.70). Granule palatability was acceptable; volunteers indicated they would take it again. Selumetinib was well-tolerated; for both formulations, few adverse events of mild intensity were reported; dry eyes (fasted) versus dry eyes and rhinorrhea (fed) were most frequent. This was the first study to test the granule formulation in humans; results indicate the granule formulation has similar AUC to the capsule formulation and minimal food effect, supporting planned clinical trials in pediatric patients.
CTNI-13. UPDATES ON CLINICAL OUTCOMES AND TUMOR RECURRENCE PATTERNS OF A HUMAN PILOT STUDY ASSESSING EFFICACY OF BELINOSTAT (PXD-101) COMBINING WITH CHEMORADIATION IN TREATING GLIOBLASTOMA
Authors: Xu Karen , Huang Vicki , Ramesh Karthik , Gurbani Saumya , Schreibmann Eduard , Weinberg Brent , Sengupta Soma , Voloschin Alfredo , Holdhoff Matthias , Barker Peter , Kleinberg Lawrence , Olson Jeffrey , Shim Hyunsuk , Shu Hui-Kuo 
Published: December 2020

Abstract

INTRODUCTION
Glioblastoma (GBM) is highly aggressive with poor prognosis. Belinostat is a histone deacetylase inhibitor with blood–brain barrier permeability that has anti-GBM activity and may enhance effects of chemoradiation. Our institution conducted a clinical trial evaluating clinical efficacy of belinostat with standard-of-care therapy for GBMs.

METHODS
13 and 14 patients were enrolled into cohort 1 (c1, control) or cohort 2 (c2, belinostat) with 12 in each group with sufficient follow-up MRIs for recurrence analysis. All patients received concurrent, adjuvant temozolomide and focal radiation therapy (RT). For c2 patients, the belinostat regimen (500-750mg/m2 1x/day x 5 days) was given over three cycles every 3 weeks (weeks -1, 2, and 5 of RT). RT margins of 5–10 mm and 3 mm were added to generate clinical tumor volumes and planning target volumes (PTVs). PTV1 (based on FLAIR MRI) and PTV2 (based on CE-T1w MRI) received 51 and 60 Gy, respectively, over 30 fractions. Volume at initial recurrence (rGTV) was contoured.

RESULTS
Mean age was 58.3 years for c1 and 51.1 years for c2. Patient/tumor characteristics were similar between cohorts. Median OS were 16.6 and 18.5 months for c1 and c2 (p=0.538), respectively. Average minimum, maximum and mean radiation dose to rGTV was 54.1 Gy, 64.2 Gy and 62 Gy, for c1, and 47.5 Gy, 57.6 Gy and 53.5 Gy, for c2 (p=0.322, 0.088 and 0.071), respectively. The mean overlap between rGTV and PTV1/PTV2 for c1 & c2 were 99.2% & 96.9%/99.8% & 78.7% (p=0.489/0.133), respectively.

CONCLUSION
Median OS was slightly longer for c2 though not statistically significant. rGTV in c1 received higher radiation doses and had more overlap with PTV2 than in c2. Out-of-field recurrence appears more likely in c2 suggesting better infield control with belinostat. This study highlights the potential of belinostat as a synergistic therapeutic agent for GBM treatment.
CTNI-15. CLINICAL EFFICACY OF ONC201 IN NEWLY DIAGNOSED DIPG AND IN PREVIOUSLY IRRADIATED PEDIATRIC H3 K27M-MUTANT GLIOMAS
Authors: Gardner Sharon , Koschmann Carl , Tarapore Rohinton S , Allen Jeffrey , Zaky Wafik , Odia Yazmin , Hall Matthew , Daghistani Doured , Khatib Ziad , Aguilera Dolly , MacDonald Tobey , Fouladi Maryam , McGovern Susan , Mueller Sabine , Kline Cassie , Vitanza Nicholas , Lu Guangrong , Allen Joshua , Khatua Soumen 
Published: December 2020

Abstract
ONC201, an anti-cancer DRD2 antagonist and ClpP agonist, is in Phase II trials for adult H3 K27M-mutant diffuse midline gliomas. In adults, the recommended phase 2 dose (RP2D) of 625mg ONC201 once a week has been established as a biologically active dose that is well tolerated. Radiographic regressions with single agent ONC201 have been reported in adult recurrent H3 K27M-mutant glioma patients. This multi-arm, dose-escalation and dose-expansion trial determined the pediatric RP2D of ONC201 administered as an oral capsule (Arm A) or liquid formulation (Arm E) in post-radiation H3 K27M-mutant glioma (Arm A) or in newly diagnosed DIPG (Arm B) patients. Molecular assessments include intratumoral ONC201 concentrations (Arm C) and CSF H3 K27M DNA levels (Arm D). Enrollment as of April 30, 2020 is complete in Arm A (22) and Arm E (26) and continues in Arm B (18/24), Arm C (5/12), and Arm D (22/24). The RP2D of weekly 625mg ONC201 scaled by body weight was confirmed when administered as a capsule or a liquid formulation as a single agent or in combination with radiation without dose-limiting toxicity. The most frequent adverse events regardless of attribution to the drug were predominantly low grade: ONC201 capsule alone was headache (54.5%), nausea (36.4%), and fatigue (36.4%); ONC201 liquid formulation was vomiting (31.8%), headache (22.7%), VIth nerve disorder (22.7%); ONC201 capsules in combination with radiation (Arm B) was headache (47.1%), vomiting (52.9%), nausea (41.2%). Pharmacokinetic analysis in plasma of Arm A patients revealed T1/2: 8.4h; Tmax: 2.1h; Cmax: 2.3ug/mL; AUC0-tlast: 16.4ug/mL, with similar exposure across body weights. In conclusion, when scaled by body weight the ONC201 capsule or liquid formulation alone or in combination with radiation were associated with safety and pharmacokinetic profiles in pediatric H3 K27M-mutant diffuse midline glioma patients that are similar to the experience in adults.
CTNI-16. FEASIBILITY PILOT STUDY OF OKN-007 IN COMBINATION WITH ADJUVANT TEMOZOLOMIDE CHEMORADIOTHERAPY IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA
Authors: Battiste James , Sung Sarah , Wright Deborah , Glenn Chad , Algan Ozer , Teague April , Zhao Yan , Cohoon Andrew , Kim Hyun Sook , Towner Rheal 
Published: December 2020

Abstract

BACKGROUND
Temozolomide (TMZ) is the standard of care chemotherapy agent for glioblastoma. Unfortunately, intrinsic or acquired resistance eventually renders TMZ ineffective. The novel anti-cancer agent OKN-007 plus TMZ increased survival in glioma-bearing mice compared to TMZ alone. Furthermore, OKN-007 increased TMZ sensitivity in both TMZ-sensitive and TMZ-resistant cell lines. Therefore, we initiated a clinical trial (NCT03587038) of OKN-007 in combination with TMZ and radiation therapy (RT). Here we report the safety and tolerability findings of this trial in-progress.

METHODS
Adults with newly-diagnosed and resected GBM are eligible. OKN-007 is administered by IV at 60 mg/kg. There are three treatment phases: Concomitant, Pre-Maintenance, and Maintenance. In the Concomitant Phase, patients receive OKN-007 three times per week (Cohort 1) or five times per week (Cohort 2); all patients receive TMZ at 75 mg/m2 daily and RT at 60 Gy over 30 fractions. In the 28-day Pre-Maintenance Phase, all patients receive OKN-007 thrice weekly. In the Maintenance Phase (MP), comprising up to eighteen 28-day cycles, TMZ is dosed at 150–200 mg/m2 on days 1–5 of each cycle for six cycles. OKN-007 is administered thrice weekly for six cycles, then twice weekly for three cycles, then once weekly for nine cycles. An expansion cohort of up to 25 patients will use the highest tolerated dosing protocol.

RESULTS
To date, five patients have been enrolled. Three patients in Cohort 1 and one in Cohort 2 advanced to the MP, and no dose-limiting toxicities (DLTs) occurred. One patient in Cohort 2 was removed due to a DLT (grade 3 neutropenic fever).

CONCLUSIONS
The treatment plan in Cohort 1 appears safe and well-tolerated. Recruitment for Cohort 2 is ongoing and will be expanded to further evaluate safety. Once the outcome of Cohort 2 is known, the regimen for the expansion cohort will be determined.
CTNI-17. CLINICAL EFFICACY AND PREDICTIVE BIOMARKERS OF ONC201 IN H3 K27M-MUTANT DIFFUSE MIDLINE GLIOMA
Authors: Rahman Kawakibi Abed , Tarapore Rohinton S , Gardner Sharon , Thomas Chase , Cartaxo Rodrigo , Yadav Viveka Nand , Chi Andrew , Kurz Sylvia , Wen Patrick , Arrillaga-Romany Isabel , Batchelor Tracy , Butowski Nicholas , Sumrall Ashley , Shonka Nicole , Harrison Rebecca , de Groot John , Mehta Minesh , Odia Yazmin , Hall Matthew , Daghistani Doured , Cloughesy Timothy , Ellingson Benjamin , Umemura Yoshie , Garton Hugh , Franson Andrea , Robertson Patricia , Schwartz Jonathan , Cantor Evan , Miklja Zachary , Mullan Brendan , Bruzek Amy , Siada Ruby , Cummings Jessica , Paul Alyssa , Wolfe Ian , Jiang Li , Filbin Mariella , Vats Pankaj , Kumar-Sinha Chandan , Mody Rajen , Chinnaiyan Arul , Venneti Sriram , Lu Guangrong , Mueller Sabine , Martinez Daniel , Resnick Adam , Nazarian Javad , Waszak Sebastian , Allen Joshua , Koschmann Carl 
Published: December 2020

Abstract
Patients with diffuse midline glioma (DMG) harboring H3 K27M mutation rarely survive longer than two years and have no proven therapies following first-line radiation. ONC201, a bitopic DRD2 antagonist and allosteric ClpP agonist, has shown encouraging efficacy in early phase studies in H3 K27M-mutant DMG. In order to define response rates in H3 K27M DMG patients and to clarify the genomic, anatomic and molecular predictors of response, we performed an integrated pre-clinical and clinical analysis of ONC201 treatment. ONC201 was effective in intra-uterine electroporation (IUE)-generated H3 K27M-mutant murine glioma models with excellent CNS penetration and survival benefit. Patients with H3 K27M-mutant DMG treated with ONC201 on active clinical trials (n=50, 27 thalamic, 23 brainstem) showed an overall survival (OS) of 28.1 (range: 5.9–105) months from diagnosis (enrollment by 4/29/19, data cut-off 12/28/19), compared to historical median OS of 12 months. Median OS for non-recurrent patients has not been reached (n=16, median follow-up: 16.8 from diagnosis). For non-recurrent thalamic patients (n=8), median PFS is 20.1 (range: 9.3–27.6) months from diagnosis (median time on drug: 14.5 months). Best response for thalamic patients by RANO: 1 CR, 5 PR, 7 SD, 8 PD, 6 not reported. Decreased H3 K27M cell-free tumor DNA in plasma and CSF at 6 months correlated with long-term response. Baseline tumor gene expression profiling in patients treated with ONC201 (n=14) identified EGFR and the cortical developmental transcription factor FOXG1 as the strongest biomarkers of radiographic response to ONC201. Analysis of 541 ONC201-treated human cancer cell lines from DepMap, provided evidence for an EGFR-dependent ONC201 resistance mechanism. Analysis of 38 glioma cell lines further supports FOXG1 as a glioma-specific predictive biomarker of ONC201 response. The unprecedented survival results and radiographic responses to ONC201 in H3K27M DMG make a compelling case for later phase and combinatorial studies.