Abstract Purpose: We conducted a phase I trial to evaluate radiotherapy (RT) and nivolumab with the further addition of an indoleamine 2,3-dioxygenase 1 (IDO1) enzyme inhibitor (BMS-986205) in newly diagnosed patients with glioblastoma (GBM) IDH wild-type. Patients and Methods: In the current study, there were two primary cohorts of individuals. Cohort A included patients with O6-methylguanine-DNA methyltransferase (MGMT)–unmethylated GBM who received RT with concurrent and adjuvant nivolumab with escalating BMS-986205 doses. Cohort B included patients with MGMT-methylated GBM who received BMS-986205 at 25 mg daily with RT, nivolumab, and temozolomide (TMZ) followed by adjuvant TMZ. Patient outcomes were correlated with flow cytometric, transcriptome, general metabolite, and microbial metabolite analyses. Results: The treatments for both cohorts were moderately safe and tolerable. The treatment-emergent adverse events (TEAE) were mostly related to RT, TMZ, or the underlying disease and tumor progression. In cohort A, serious adverse events and TEAEs were predominantly lower grade, with no differences between the IDO1 enzyme inhibitor dosing cohorts. Dose-limiting toxicities reflected by increased transaminases (grade 3) were observed in two and three patients at the 50 and 100 mg levels of BMS-986205, respectively, with malaise observed in the 50 mg arm only. The 50 mg daily schedule was established as the recommended phase II dose (RP2D) in combination with RT and nivolumab. A number of exploratory correlative studies were also conducted. Conclusions: This single-arm, small phase I trial establishes a safety profile and RP2D for RT in combination with nivolumab and BMS-986205 for newly diagnosed patients with MGMT-unmethylated GBM (ClinicalTrials.gov: NCT04047706).

This phase I trial evaluated the IDO1 enzyme inhibitor, BMS-986205, with radiation (RT) and nivolumab treatment in newly diagnosed patients with GBM IDHwt. Cohort A received RT + nivolumab with escalating BMS-986205 doses in MGMT unmethylated GBM patients. Cohort B received the highest dose of BMS-986205 with nivolumab and standard RT/temozolomide (TMZ) TMZ in MGMT methylated GBM patients. The treatments were found to be safe and tolerable. The median overall survival was 11.5 (95% CI: 3.71, 33.8) and 26.9 months (95% CI: 8.94-NR) while the 2-year survival rates were 33% (95% CI: 10.3%, 58.8%) and 60% (95% CI: 12.6%, 88.2%) for MGMT unmethylated and methylated GBM, respectively. Longer patient survival was associated with higher CD8+ T cell levels, higher microbial aryl-lactate levels, higher abundance of Massilioclostridium coli, Dysosmobacter welbionis, and Phocaeicola plebeius in the stool, a younger age, and a lack of gross total resection. (ClinicalTrials.gov: NCT04047706).

Patients with solid tumor brain metastases that progress after whole-brain radiation have limited options. This prospective trial investigated the efficacy, safety, and tolerability of bevacizumab as salvage therapy in this population. Eligible patients received bevacizumab 10 mg/kg intravenously every 2 weeks until progression. The primary endpoint was radiologic response using Response Assessment in Neuro-Oncology (RANO) criteria. The secondary endpoints were progression-free survival (PFS), overall survival (OS), duration of response, and safety. Quality of life (QOL) was studied using the Functional Assessment of Cancer Therapy-Brain (FACT-Br) scale. Twenty-seven patients were enrolled, with twenty-four having evaluable data for response. The majority of histologies (n = 21, 78%) were breast cancer. The remaining histologies were non-small-cell lung cancer (n = 4, 15%), neuroendocrine cancer (n = 1, 3%), and papillary fallopian serous adenocarcinoma (n = 1, 3%). Eighteen patients had radiologic response, with two patients demonstrating partial response (8.33%) and sixteen patients demonstrating stable disease (66.7%). The median duration of response was 203 days. PFS at 6 months was 46%, median PFS was 5.3 m, and median OS was 9.5 m. Treatment was well tolerated, with six patients experiencing grade 3 lymphopenia and hypertension. There was one grade 3 thromboembolism. QOL was not negatively impacted. Bevacizumab is a safe and feasible salvage treatment with durable response and favorable overall survival for patients with progressive brain metastases after whole-brain radiation.

Abstract BACKGROUND IDHwt glioblastoma with unmethylated MGMT gene promoter carries a poor prognosis. Preclinical studies have shown that combination of radiotherapy and dual immunotherapy with nivolumab and IDO inhibition significantly prolongs survival of mice with an orthotopic glioblastoma [Ladomersky, et al. CCR 2018;24(11):2559-2573]. In a clinical trial in patients with newly diagnosed glioblastoma with unmethylated MGMT we substituted temozolomide for dual immunotherapy combination. METHODS Phase 1 trial [NCT04047706] using a 3 + 3 dose-escalation design. All received standard radiotherapy (30 x 2 Gy) with addition of once daily oral BMS-986205 and intravenous nivolumab (240mg every 2 weeks) begining on day 1 of radiotherapy and continuing until disease progression or intolerance. BMS-986205 dosing was increased from 50 mg to 100 mg. DLT period encompasses 6 weeks of radiotherapy and the 4 subsequent weeks. Immunocorrelatives being conducted before and after treatment include mass spectrometry for tryptophan and kynurenine levels, immunohistochemistry of resected tumor, and RNA-sequencing and flow cytometric analysis of PBMCs. RESULTS Twelve patients were treated on 2 dose levels of BMS-986205 (50, 100 mg). Treatment-emergent toxicity was as expected for this population. Three (25%) treatment-related SAEs were reported. Dose limiting toxicity of grade 3 transaminase elevation was observed in 2 patients at the 100 mg dose level, while at lower doses of BMS-986205 no substantial alterations of liver enzymes was observed. No other relevant treatment related toxicity occured. Ongoing immunocorrelative profiling and preliminary outcome data (all patients minimal follow-up >12 months) will be available at the time of the meeting. CONCLUSIONS Dose limiting toxicity of BMS-986205 in combination with nivolumab and radiotherapy is hepatic (reversible) transaminitis. The recommended dose for further investigation is 50 mg. Accrual is ongoing for the MGMT promoter methylated cohort using the same regimen without withholding temozolomide. A randomized phase 2/3 trial is approved within the NRG network.

2070 Background: Brain metastases (BM) are the most common intracranial malignancy with overall a poor prognosis estimated at approximately 4 months from time of initial diagnosis for treated patients, and even lower after failing WBRT after which treatment options have been limited and outcomes poor. Methods: This is an open label phase 2 study where patients who have previously failed WBRT received bevacizumab at a dose of 10 mg/kg intravenously every two weeks until CNS disease progression with one cycle being defined as 4 weeks. The primary endpoint was objective radiographic tumor response as defined by modified Response Assessment in Neuro-oncology (RANO) criteria. Secondary endpoints included progression free survival (PFS) at 6 months, time to progression, time to response, duration of response, overall survival (OS), quality of life (QOL) as measured by the FACT-G and FACT-Br and safety. Results: A total of 27 patients were consented and registered to study of which 24 were evaluable for ORR (3 came off study prior to first follow up MRI brain). Medianage was 53 (range 27-73), median number of cycles was 5.5 (range 1-20) with a median follow up of 8.7 months (range 2.4-47.9mo). Of the 24evaluable patients, there were 6 Partial response, 16 stable disease and 2progressive disease. The 6 month PFS: 46% (95% CI: 25% - 67%) and median PFS was 5.3 months. Median OS was 9.5 months (95% confidence interval 6.3m – 15.0m). For the patients who completed sequential QOL assessments, there was no significant decline in QOL but there was a nonsignificant improvement in the FACT-Br scores. Overall, treatment was well tolerated with 3grade 3 adverse events seen: hypertension (n = 3), headache (n = 1) and thrombotic event (n = 1). Conclusions: For this WBRT failure BM population, we were able to show a 25% disease response to bevacizumab therapy along with good drug tolerability and no noted central nervous system bleeding. Improved survival as compared to historical controls was seen 9.5 m. Of the 24 evaluable patients, 81% (22/24) experienced clinical benefit defined as stable disease or better. Bevacizumab therapy could be a viable option for solid tumor BM patients who experience progression following WBRT, however a larger trial is required to confirm this data. Clinical trial information: NCT01898130.

Abstract BACKGROUND Brain metastases (BM) are the most common intracranial tumor with limited treatment options following the progression after WBRT. METHODS This open label phase 2 study for patients have progressed following WBRT enrolled participants who received bevacizumab 10 mg/kg intravenously every two weeks until CNS disease progression (one cycle=4 weeks). The primary endpoint was objective radiographic tumor response as defined by modified Response Assessment in Neuro-oncology (RANO) criteria. Secondary endpoints included safety, progression free survival (PFS), time to response, duration of response, overall survival (OS), and quality of life (QOL) as measured by FACT-G and FACT-Br. RESULTS A total of 27 patients were registered of which 24 were evaluable for ORR (3 came off study prior to first follow up MRI brain). Median age was 53 (range 27–73), median number of cycles was 5.5 (range 1–20) with a median follow up of 8.7 months (range 2.4–47.9mo). Of the 24 evaluable patients, 6 showed radiographic response (Partial response=6, stable disease=16, progressive disease=2, 81% (22/24) experienced clinical benefit). The 6 month PFS: 46% (95% CI: 25% - 67%) and median PFS was 5.3 months. Median OS was 9.5 months (95% confidence interval 6.3m – 15.0m). For the patients who completed sequential QOL assessments, there no decline in QOL seen secondary to treatment and there was a non statistically significant improvement seen in the FACT-Br questionnaire. Overall, treatment was well tolerated with 3 grade 3 adverse events seen: hypertension (n=3), headache (n=1) and thrombotic event (n=1). CONCLUSION For this pretreated BM population with historically poor clinical outcome and survival, we showed disease response with bevacizumab therapy, drug tolerability and improved survival as compared to historical controls. While larger studies are needed to confirm, bevacizumab therapy could be a viable option for solid tumor BM patients who experience progression following WBRT.

3012 Background: Glioblastoma is a difficult to treat tumor with therapeutics limited by their ability to cross the blood brain barrier. SNAs, i.e., gold nanoparticle cores covalently conjugated with a corona of densely packed, highly oriented siRNA oligonucleotides targeted to the GBM oncogene BCL2L12, represent a novel class of blood-brain and blood-tumor barrier-permeable nanomedicinal conjugates, for suppressing gene expression in the tumors of GBM patients. Methods: This is a single-arm, open-label, “window of opportunity” phase 0 first-in-human trial to determine the safety and bioavailability of a novel nanotherapeutic compound, NU-0129. Enrolled patients were treated with intravenous NU-0129 at the dose of 0.04mg/kg. This treatment dosing was considered microdosing defined as 1/50ththe NOAEL (no observed adverse event level) from non-human primate studies. Treatment was followed by tumor resection 8-48 hours later. Primary outcome patient safety and toxicity was monitored weekly for 3 weeks post-infusion. Secondary objectives included biodistribution of NU0129 in tissue, evaluation of pharmacokinetics of NU0129 and the feasibility of NU0129 administration. Exploratory objectives included Bcl2L12 expression and post treatment apoptotic markers as well as progression free survival and overall survival rates. Results: 8 patients were enrolled, treated and subsequently underwent surgical resection. No significant treatment related toxicities were seen. Severe ( > grade 3) adverse events were observed in two patients: hypophosphatemia (one grade 3, one grade 4) and one patient with grade 3 lymphopenia, all were considered as “possibly related” by treating oncologists. In 6 of the 8 patients sufficient tumor tissue was available for analysis of gold accumulation by ICP-MS (inductively coupled plasma-mass spectrometry), and gold accumulation was seen in the tumor tissue of all 6 of these patients. Conclusions: Macrodosing of the nanotherapeutic NU-0129 was well tolerated in glioblastoma patients with no unexpected adverse effects and showed initial evidence of crossing blood brain barrier. Immunohistochemistry for Bcl2L12 expression, apoptotic markers, and PK studies are pending. The demonstration of gold nanoparticles in the tumor tissue validates this approach for drug delivery. Clinical trial information: NCT03020017.