FGFR4-CAR T Cells

Single intravenous (IV) infusion on Day 0

30 mg/m2 per day IV on days -5, -4, -3, -2

Background: * Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood with an annual incidence of 4.5 cases per 1 million children and is the third most prevalent extracranial solid tumor of childhood after neuroblastoma and Wilms tumor. * RMS is divided into two main subtypes, fusion negative (FN-RMS) driven by RAS pathway mutations, and fusion positive rhabdomyosarcoma (FP-RMS) driven by PAX3/PAX7-FOXO1 fusion genes.

Background: Rhabdomyosarcoma (RMS) is a cancer of soft tissues. It is the most common soft tissue sarcoma seen in children. RMS cancer cells have a protein called FGFR4 on their surface. Researchers want to try a new kind of treatment for RMS: They will collect a person s own T cells, a type of immune cell; then they will change the T cells so they are better able to target the FGFR4 protein and attack RMS tumor cells.

The modified T cells are chimeric antigen receptor (CAR) T cells. The treatment in this study is called FGFR4-CAR T cells. Objective: To test FGFR4-CAR T cells in children and young adults with RMS. Eligibility: People aged 3 to 39 years with RMS. The RMS must have failed to respond or returned after at least 2 rounds of standard treatment. Design: Participants will be screened. They will have physical exam, imaging scans, blood tests, and tests of their heart.

Live record on ClinicalTrials.gov →

• Histologically confirmed rhabdomyosarcoma by the NCI Department of Pathology.
• Note: Since FGFR4 expression is universal in rhabdomyosarcoma, confirmation of FGFR4 expression is not required.
• Relapsed or refractory rhabdomyosarcoma after at least two (2) cancer treatment regimens i.e., participants should have relapsed or progressed after upfront therapy (that includes any systemic chemotherapy with or without local control) as well as at least one salvage therapy (which can be systemic therapy, radiation, or surgery).
• No available alternative curative therapies per standard of care.
• Participants must have measurable disease per RECIST 1.1 or non-measurable disease on imaging.
• Age \>= 3 and \<= 39 years old.

Inclusion criteria as written on the registry, trimmed. The full list, with exclusions, is on the live record.