Groot, John Frederick De

Abstract BACKGROUND Liquid biopsy in glioblastoma (GBM) is hindered by a lack of requisite circulating tumor (ct) and cell-free (cf) DNA levels in blood due to the blood-brain barrier (BBB). This limits the identification of blood-based tumor biomarkers along with the development and use of biomarker-driven systemic therapies. Real-time image-guided low intensity focused ultrasound (LIFU) combined with intravenously administered microbubble oscillators, leads to non-invasive disruption of the BBB. This trial aims to evaluate the utility of LIFU for boosting blood ctDNA and cfDNA for enhanced liquid biopsy in GBM patients. MATERIAL AND METHODS LIBERATE is an ongoing, prospective, multi-center, self-controlled, pivotal trial evaluating safety and technical efficacy of LIFU-based BBB disruption for increasing blood ctDNA and cfDNA levels in adults, aged 18-80 years with GBM. Patients with suspected GBM planned for tumor biopsy or resection at ten centers in the US are being enrolled. Patients with multifocal tumors or tumors arising from deep midline, thalamus, cerebellum, or brainstem are excluded. Patients are administered IV microbubbles for enhanced sonication effects, after which MR-guided BBB disruption using a 220 kHz LIFU device is performed with real-time acoustic feedback control for effective microbubble activation. Before and after procedure, phlebotomy and MRI brain are performed to evaluate outcomes. Primary study endpoint is defined, per subject, as ratio between their cfDNA level in blood 1-hour post-LIFU procedure compared to cfDNA level in blood pre-procedure. Primary study hypothesis is that BBB disruption with LIFU leads to a ≥2-fold rise in blood cfDNA. The secondary hypothesis is that there exists ≥75% agreement between biomarker pattern in blood cfDNA sample obtained 1-hour post-LIFU and the biomarker pattern in tumor tissue obtained later. The trial has been powered to evaluate both primary and secondary hypotheses. Based on an assumed true agreement rate of 91% and a one-sided alpha of 0.025, an exact test for binomial proportions provides a sample of N = 50 with 84% power for the secondary hypothesis. Exploratory endpoints include (1) sensitivity of detection of known specific somatic mutations in ctDNA from blood samples collected before and after LIFU, (2) estimation of ctDNA levels post-LIFU in samples collected at 30 minutes, 1 hour, 2 hour, and 3 hour to determine the time of greatest yield, (3) correlation of MRI parameters related to grading of BBB disruption and ctDNA-based biomarkers from post-LIFU blood samples. RESULTS Patient enrollment commenced in 2022, and 22 patients have been recruited by 05/2024. CONCLUSION Findings from this trial will be critical to liquid biopsy in GBM (Clinical trial information: NCT05383872).

TPS2098 Background: Liquid biopsy in glioblastoma (GBM) is hindered by a lack of requisite circulating tumor (ct) and cell-free (cf) DNA levels in blood due to the blood-brain barrier (BBB). This limits the identification of blood-based tumor biomarkers along with the development and use of biomarker-driven systemic therapies. Real-time image-guided low intensity focused ultrasound (LIFU) combined with intravenously administered microbubble oscillators, leads to non-invasive disruption of the BBB. This trial aims to evaluate the utility of LIFU for boosting blood ctDNA and cfDNA for enhanced liquid biopsy in GBM patients. Methods: LIBERATE is an ongoing, prospective, multi-center, self-controlled, pivotal trial evaluating safety and technical efficacy of LIFU-based BBB disruption for increasing blood ctDNA and cfDNA levels in adults (aged 18-80 years) with GBM. Patients with suspected GBM planned for tumor biopsy or resection at ten centers in the US are being enrolled. Patients with multifocal tumors or tumors arising from deep midline, thalamus, cerebellum, or brainstem are excluded. Patients are administered IV microbubbles for enhanced sonication effects, after which MR-guided BBB disruption using a 220 kHz LIFU device is performed with real-time acoustic feedback control for effective microbubble activation. Before and after procedure, phlebotomy and MRI brain are performed to evaluate outcomes. Primary study endpoint is defined, per subject, as ratio between their cfDNA level in blood 1-hour post-LIFU procedure compared to cfDNA level in blood pre-procedure. Primary study hypothesis is that BBB disruption with LIFU leads to a ≥2-fold rise in blood cfDNA. The secondary hypothesis is that there exists ≥75% agreement between biomarker pattern in blood cfDNA sample obtained 1-hour post-LIFU and the biomarker pattern in tumor tissue obtained later. The trial has been powered to evaluate both primary and secondary hypotheses. Based on an assumed true agreement rate of 91% and a one-sided alpha of 0.025, an exact test for binomial proportions provides a sample of N = 50 with 84% power for the secondary hypothesis. Exploratory endpoints include (1) sensitivity of detection of known specific somatic mutations in ctDNA from blood samples collected before and after LIFU, (2) estimation of ctDNA levels post-LIFU in samples collected at 30 minutes, 1 hour, 2 hour, and 3 hour to determine the time of greatest yield, (3) correlation of MRI parameters related to grading of BBB disruption and ctDNA-based biomarkers from post-LIFU blood samples. Patient enrollment commenced in 2022 and 22 patients have been recruited by January 2024. Clinical trial information: NCT05383872 .

TPS2084 Background: Liquid biopsy in glioblastoma (GBM) is hindered by a lack of requisite circulating-free DNA (cfDNA) levels in blood due to the blood-brain barrier (BBB). This results in challenges to the identification of blood-based biomarkers and the development of novel biomarker-driven systemic therapies. Real-time image-guided low intensity focused ultrasound (LIFU) combined with IV microbubble oscillators (DEFINITY), non-invasively causes BBB disruption (BBBD). This clinical trial aims to evaluate the utility of LIFU for increasing cfDNA in blood for liquid biopsy in GBM. Methods: LIBERATE is a prospective, multi-center, self-controlled, ongoing, pivotal trial evaluating safety and technical efficacy of LIFU for BBBD to increase cfDNA in blood for GBM. Patients aged >18-80 years with suspected GBM planned for tumor biopsy or resection at eleven centers in North America are being included. Patients with multifocal tumors or tumors arising from deep midline, thalamus, cerebellum, or brainstem are excluded. Patients are administered IV oscillating microbubbles for enhancing sonication, after which MR-guided BBBD using a 220 kHz LIFU device is performed with real-time acoustic feedback for effective cavitation. Before and after procedure, phlebotomies and MRI brain are performed to evaluate outcomes. The primary study endpoint is defined, per subject, as the ratio between their cfDNA level in blood 1-hour post-LIFU compared to cfDNA level in blood pre-procedure. The primary study hypothesis is that BBBD with LIFU leads to ≥2-fold increase in cfDNA in blood. The secondary hypothesis is that there exists ≥75% agreement between biomarker pattern in cfDNA sample from 1-hour post-LIFU sample and biomarker pattern in tumor tissue obtained later. The trial has been powered to evaluate both primary and secondary hypotheses. Based on an assumed true agreement rate of 91% and a one-sided alpha of 0.025, an exact test for binomial proportions provides a sample of N=50 with 84% power for the secondary hypothesis. Exploratory endpoints include (1) sensitivity of detection of known somatic mutations in cfDNA from blood samples collected before and after LIFU, (2) estimation of cfDNA levels post-LIFU in samples collected at 30 minutes, 1 hour, 2 hour, and 3 hour to determine time of greatest yield, (3) correlation of MRI parameters related to grading of BBBD and biomarkers positive in cfDNA from post-LIFU blood samples. Patient enrollment commenced in 2022 and 7 patients have been recruited by 02/13/2023. Clinical trial information: NCT05383872 .

2017 Background: Response Assessment in Neuro-Oncology (RANO) criteria for high-grade and low-grade glioma (HGG and LGG) were developed to improve reliability of response assessment in glioma trials. Several limitations of the original RANO criteria have been reported. Methods: To address limitations of the original RANO criteria, a large cohort of patients with newly diagnosed and recurrent glioblastoma were evaluated comparing RANO-HGG with modified RANO (mRANO) and immunotherapy RANO (iRANO) criteria to inform the following proposed updates (RANO 2.0). Results: Based on the 2021 WHO classification of glioma, we recommend a single common set of criteria for all gliomas regardless of WHO grade and IDH mutational status. These criteria will be used for all trials regardless of the treatment modalities being evaluated. In newly diagnosed glioblastoma, the post-radiotherapy MRI, usually obtained approximately 4 weeks after completion of radiotherapy, rather than the post-surgical MRI as proposed in original RANO criteria, will be used as the baseline for comparison of subsequent scans. Since the incidence of pseudoprogression is high in the first 3 months following radiotherapy, confirmation of progression during this period with a repeat MRI (in 4-8 weeks) will be required for determining radiographic progression of disease (PD) if the patient is clinically stable. However, confirmation scans are not mandatory after this period nor for recurrent tumors since these scans do not appear to improve reliability in determining progression. For agents with a high likelihood of producing pseudoprogression such as viral therapies and some other immunotherapies, mandatory confirmation of progression with a repeat MRI is an option. The primary measurement will remain the 2-dimensional maximum cross-sectional area of tumor as the simplest method, but where resources are available, volumetric measurements are an option. For IDH wild-type tumors with contrast enhancement, non-enhancing tumor will no longer be evaluated with the possible exception of patients receiving antiangiogenic therapies. However, in tumors with a significant non-enhancing component, both the contrast enhancing and non-enhancing components will be evaluated as target lesions. Conclusions: We hope that these and other proposed changes by the RANO working group will improve response assessment in glioma clinical trials and help the development of more effective therapy for patients.

2016 Background: Among the primary aims of new therapies for glioblastoma (GBM) are the reduction of morbidity and restoration or preservation of quality of life (QoL). Selinexor (SEL) is a first-in class, oral, selective inhibitor of nuclear export which blocks exportin 1 (XPO1), forcing the nuclear retention and reactivation of tumor suppressor proteins, ultimately causing cell death in cancer cells. SEL is approved for the treatment of previously treated multiple myeloma and DLBCL. XPORT-GBM-029 (NCT04421378) is a phase 1 dose finding study followed by an open-label randomized phase 2, 3-arm trial to evaluate SEL in combination with standard therapies for newly diagnosed and recurrent GBM: Arm A (ndGBM, uMGMT) – radiation +/- SEL; Arm B (ndGBM, mMGMT) – radiation and temozolomide +/- SEL; Arm C (rGBM) – lomustine +/- SEL at first relapse. We look to identify sensitive, reliable, and clinically meaningful digital assessments of the functional status of ndGBM and rGBM patients via a patient-centric approach. Methods: XPORT-GBM-029 incorporates standard clinical and imaging evaluations of GBM progression with novel digital tools that objectively measure motor and cognitive function. The study is conducted at 50 sites globally with the aim of enrolling 350 patients with newly diagnosed and recurrent GBM. Following discussions with KOLs and patient advocacy partners at EndbrainCancer, we surveyed GBM patients and their caregivers to identify disease manifestations critical to patients’ QoL. The survey revealed four key areas impacting patients’ QoL that can be affected by GBM therapies and can be objectively monitored: cognitive function, lateralization, fatigue, and sleep. In this trial we use objective measurements to evaluate SEL’s effects on GBM patients’ QoL. Patients wear inertial sensors to measure their activity and sleep and complete a cognitive battery at baseline and before each MRI. Results: Associations between objective digital measures of activity, gait, fatigue, sleep, and cognition will be examined with respect to clinical assessments including physical examinations, modified Response Assessment in Neuro-Oncology (mRANO), Neurologic Assessment in Neuro-Oncology (NANO), Karnofsky Performance Score (KPS) and Patient Reported Outcome (PRO) QoL questionnaires. Descriptive summary statistics and plots are employed in exploratory data analysis, and other advanced data mining methods may also be considered. Conclusions: XPORT-GBM-029 trial is probably the first large, prospective, longitudinal study in GBM patients employing digital markers and may provide useful information regarding the utility of wearable and mobile devices for measuring functional outcomes in clinical trials. Clinical trial information: NCT04421378.

2024 Background: A major impediment to improving neuro-oncology outcomes is poor clinical trial accrual. Methods: We convened a multi-stakeholder group including Society for Neuro-Oncology, Response Assessment in Neuro-Oncology, patient advocacy groups, clinical trial cooperative groups, and other partners to determine how we can improve trial accrual. Results: We describe selected factors contributing to poor trial accrual and possible solutions. Conclusions: We will implement strategies with the intent to double trial accrual over the next 5 years. [Table: see text]

TPS2079 Background: Patient with glioblastoma (GBM) with unmethylated MGMT promoters derive limited benefit from temozolomide (TMZ) and have dismal outcome. Prioritizing the numerous available therapies and biomarkers for late stage testing requires an efficient clinical testing platform. INSIGhT (NCT02977780) is a biomarker-based, Bayesian adaptively randomized, multi-arm phase II platform screening trial for patients with newly diagnosed GBM and unmethylated MGMT promoters. Methods: INSIGhT compares experimental arms to a common control of standard concurrent TMZ and radiation therapy (RT) followed by adjuvant TMZ. The primary endpoint is overall survival (OS). Patients with newly diagnosed, unmethylated GBM that are IDH R132H mutation negative, and with genomic data available or who consent to whole exome sequencing through the ALLELE companion study for biomarker grouping are eligible. Two experimental arms consist of concurrent RT/TMZ followed by adjuvant neratinib (EGFR, HER2, and HER4 inhibitor) or abemaciclib CDK 4/6 inhibitor), respectively, in place of TMZ. The other experimental arm is CC-115 (TORC1/2 and DNA PK inhibitor), which replaces TMZ in both the concurrent and adjuvant phases. Biomarker groups include: EGFR + patients with EGFR amplification/mutation; PI3K + patients with PIK3CA mutation/amplification, PIK3R1 mutation, AKT3amplification, PIK3C2B > 1 copy gain, or PTEN dual loss; CDK: + patients with wild-type RB1 and CDK4 amplification, CDK6 amplification, or CDKN2A > 1 copy loss. Given the lack of pretrial biomarker data and the anticipated overlap of the groups, randomization will initially be equal. As the trial progresses, randomization probabilities will be adapted based on the Bayesian estimation of the probability of treatment impact on progression-free survival (PFS). These randomization probabilities can vary among the biomarker groups so predictive biomarkers will be identified and utilized if present. Treatment arms may drop due to low probability of treatment impact on OS, and new arms may be added. Experimental arms are compared only with control and should be thought of as discrete experimental questions, with INSIGhT being open to new investigators with proposed therapeutic hypotheses. Clinical trial information: NCT02977780.