Atypical Teratoid Rhabdoid Tumor

Pilot study to determine feasibility of adding intrathecal chemotherapy and maintenance therapy after high dose chemotherapy for treatment of newly diagnosed HR-EBTs in patients less than 6 years of age.

This study is being conducted in patients with GPC3-positive brain tumors that have recurred or have not responded to standard therapy. Atypical teratoid rhabdoid tumors (ATRT) are aggressive tumors with poor outcomes and limited treatment options, particularly in young children. There is a need for new therapies that can improve outcomes while minimizing toxicity. This study evaluates a new experimental treatment using genetically engineered T cells (RADIANT-T cells) that target glypican-3 (GPC3), a protein expressed on tumor cells. These T cells are modified to express a chimeric antigen receptor (CAR) targeting GPC3, along with IL-15 and IL-21 to enhance their persistence and activity. The cells also include an inducible safety mechanism (iCasp9) that allows them to be eliminated if necessary. The purpose of this study is to determine the highest safe dose of RADIANT-T cells, evaluate their safety and side effects, assess how long they persist in the body, and determine whether they show anti-tumor activity in patients with GPC3-positive brain tumors.