EGFR806-specific CAR T Cell Locoregional Immunotherapy for EGFR-positive Recurrent or Refractory Pediatric CNS Tumors

This is a Phase 1 study of central nervous system (CNS) locoregional adoptive therapy with autologous CD4+ and CD8+ T cells that are lentivirally transduced to express an EGFR806 specific chimeric antigen receptor (CAR) and EGFRt. CAR T cells are delivered via an indwelling catheter into the tumor resection cavity or the ventricular system in children and young adults with recurrent or refractory EGFR-positive CNS tumors. The primary objectives of this protocol are to evaluate the feasibility, safety, and tolerability of CNS-delivered fractionated CAR T cell infusions employing intra-patient dose escalation. Subjects with supratentorial tumors will receive sequential EGFR806-specific CAR T cells delivered into the tumor resection cavity, subjects with infratentorial tumors will receive sequential CAR T cells delivered into the fourth ventricle, and subjects with leptomeningeal disease will receive sequential CAR T cells delivered into the lateral ventricle. The secondary objectives are to assess CAR T cell distribution within the cerebrospinal fluid (CSF), the extent to which CAR T cells egress into the peripheral circulation, and EGFR expression at recurrence of initially EGFR-positive tumors. Additionally, tumor response will be evaluated by magnetic resonance imaging (MRI) and CSF cytology. The exploratory objectives are to analyze CSF specimens for biomarkers of anti-tumor CAR T cell presence and functional activity.