Phase 1 Trial of Modified FGFR4-CAR T Cell Therapy for Children and Young Adults with Recurrent or Treatment-Resistant Rhabdomyosarcoma

What this Trial Is About

Rhabdomyosarcoma RMS is the most common soft tissue cancer in children and young adults, often difficult to treat when it returns or does not respond to standard therapies. This trial focuses on testing a new treatment called FGFR4-CAR T cells, which are immune cells modified to specifically target the FGFR4 protein found on RMS cancer cells. The study aims to find the highest safe dose of these modified T cells in patients aged 3 to 39 years who have recurrent or treatment-resistant RMS. Participants will first undergo screening with physical exams, imaging, blood tests, and heart function tests. Their own T cells will be collected through a procedure called apheresis, then modified in the lab to become FGFR4-CAR T cells. Before receiving the CAR T cells, participants will have preparative chemotherapy with fludarabine and cyclophosphamide for 4 days. On Day 0, the modified T cells will be infused intravenously. The study uses a dose-escalation approach to find the maximum tolerated dose. Participants may receive different doses depending on their group, followed by close monitoring. During the study, participants will be monitored for side effects and tumor response through regular assessments including imaging and laboratory tests. Follow-up visits will continue for up to 5 years after treatment, with additional long-term monitoring for another 10 years to observe the durability and safety of the therapy. Researchers will measure outcomes like toxicity, tumor response, progression-free survival, and CAR T cell persistence to evaluate the treatments impact.

FGFR4 Chimeric Antigen Receptor (CAR) T Cells in Children and Young Adults With Recurrent or Refractory Rhabdomyosarcoma