Brain Tumor-Specific Immune Cells (IL13Ralpha2-CAR T Cells) for the Treatment of Leptomeningeal Glioblastoma, Ependymoma, or Medulloblastoma

PRIMARY OBJECTIVES: I. Examine and describe the safety and feasibility of IL13Ralpha2-specific hinge-optimized 41BB-co-stimulatory CAR truncated CD19-expressing autologous T-lymphocytes (IL13Ralpha2-CAR T cells) through intracerebroventricular (ICV) delivery as adjuvant therapy in participants with: Ia. IL13Ralpha2+ leptomeningeal disease from glioblastoma (arm 1). Ib. IL13Ralpha2+ leptomeningeal disease from ependymoma or medulloblastoma (arm 2). II. Determine the activity of IL13Ralpha2-CAR T cells based on survival rate at 3 months for both arms. SECONDARY OBJECTIVES: I. Describe persistence, expansion and phenotype of endogenous and IL13Ralpha2-CAR CAR T cells in peripheral blood (PB), tumor cyst fluid (TCF) and cerebral spinal fluid (CSF), when available. II. Describe cytokine levels in PB, TCF, and CSF (when available) over the study period for each arm. III. Estimate the rate of disease response by Response Assessment in Neuro-Oncology Leptomeningeal Metastases (RANO LM) criteria by study arm where an active response is defined as stable disease or better. IV. Estimate rate of progression free survival at 3 months by study arm. V. Estimate rate of overall survival (OS) at 3 months by study arm. VI. In study participants who undergo post therapy biopsy/resection or autopsy: VIa. Evaluate IL13Ralpha2-CAR T cell persistence in the tumor tissue and the location of the IL13Ralpha2-CAR T cells with respect to the infusion site. VIb. Evaluate IL13Ralpha2 antigen on tumor tissue pre- and post-CAR T cell therapy. VII. Use biomathematical modeling of tumor growth to evaluate benefit of treatment. OUTLINE: Patients receive IL13Ralpha2-CAR T cells ICV over 5 minutes on day 1. Treatment repeats every 7 days for 4 cycles in the absence of disease progression or unacceptable toxicity. Patients may receive additional cycles per the discretion of the principal investigator. After completion of study treatment, patients are followed up at 30 days, months 3, 6, 9, 12, and then yearly for up to 15 years.