P10.16.A TELEMETRIC INTRACRANIAL PRESSURE MONITORING IN PEDIATRIC AND YOUNG ADULT PATIENTS AFFECTED BY REFRACTORY AND RELAPSED BRAIN TUMORS TREATED WITH GD2 CAR T-CELLS

Abstract BACKGROUND Central nervous system (CNS) tumors represent a significant unmet medical need, characterized by high mortality and morbidity. Chimeric antigen receptor (CAR) T-cell therapy is a promising treatment option; however, patients may experience tumor inflammation-associated neurotoxicity (TIAN). TIAN can lead to pseudo-progression, resulting in increased local mass effect and intracranial hypertension. This work aims to detect early increases in intracranial pressure (ICP) in brain tumor patients treated with CAR T-cells, with the goal of improving neurological outcomes, better managing TIAN, and avoiding invasive interventions and steroid use. MATERIAL AND METHODS For all patients enrolled in the phase 1 clinical trial NCT05298995 evaluating GD2 CAR T-cells in brain tumors, a ventricular catheter connected to a Rickham reservoir and a Miethke M.scio flat telemetric ICP monitoring device will be implanted prior to the infusion. ICP will be monitored at least six times daily. Clinical data, biomarkers and kinetics of CAR T-cells will be collected during the post-infusion observation period. RESULTS Fifteen patients (6 males, 9 females; median age at diagnosis: 14.8 years) with relapsed or refractory CNS tumors were treated between December 2023 and March 2025 with GD2CAR01. Tumor types included medulloblastoma or other embryonal tumors (n=8), hemispheric high-grade gliomas (n=4), diffuse midline glioma (n=1), and ependymomas (n=2). During cytokine release syndrome, patients exhibited a median ICP increase of 9.6 cmH₂O from baseline. No severe complications related to ICP increase were reported. Clinically significant intracranial hypertension was observed in only one patient, which was effectively managed through cerebrospinal fluid aspiration via the Rickham reservoir and medical therapy. CONCLUSION This monitoring strategy is designed to provide early detection of elevated ICP levels, allowing for timely interventions such as cerebrospinal fluid drainage. The telemetric devices will facilitate continuous ICP monitoring, reduce invasiveness, improve patient comfort and safety. Implementing this strategy has the potential to enhance the safety of CAR T-cell therapy in brain tumor patients at risk of developing intracranial hypertension, ultimately improving patient outcomes. Moreover, this approach could be useful for all patients with brain tumors at risk of developing hydrocephalus.