CAR T Cells for Embryonal Cancer

(SABRE Trial)

This trial tests the safety of a new treatment for certain childhood cancers that have returned or are not responding to standard treatments. The treatment uses special immune cells (T cells) modified to attack cancer cells. Specifically, it involves Selective Antigen Specific dTβRII-expressing T cells combined with B7-H3 CAR T cells. The trial seeks participants with specific cancers, such as rhabdomyosarcoma, Ewing sarcoma, neuroblastoma, or Wilms tumor, who have not had success with other treatments. Participants should have a measurable tumor and not have used steroids recently. As a Phase 1 trial, this research focuses on understanding how the treatment works in people, offering participants the opportunity to be among the first to receive this innovative therapy.

The trial requires that certain medications be stopped before participation. For example, you must wait at least 3 weeks after myelosuppressive chemotherapy and monoclonal antibodies, and at least 7 days after hematopoietic growth factors. It's best to discuss your specific medications with the trial team to understand any necessary changes.

Research has shown that B7-H3 CAR T cells might not harm normal tissues that also express B7-H3. This finding is significant because it suggests the treatment might not attack healthy cells. Additionally, these cells have demonstrated good growth and memory cell formation, indicating potential long-term effectiveness.

However, as this is a phase I study, researchers are primarily focused on understanding safety and determining the appropriate dose. In phase I trials, the treatment is tested in humans for the first time, so information about its side effects is limited. This phase aims to ensure the treatment's safety and establish the correct dose.

Researchers are excited about this treatment for embryonal cancer because it combines selective antigen-specific dTβRII-expressing T cells with B7-H3 CAR T cells, offering a novel approach to attacking cancer cells. Unlike traditional treatments such as surgery, radiation, or chemotherapy, which can affect healthy tissues, this treatment focuses on harnessing the body's immune system to target cancer cells more precisely. The unique combination of these T cells aims to improve the precision and effectiveness of the immune response, potentially reducing damage to healthy cells and enhancing overall outcomes for patients.

Research has shown that a new treatment using CAR T cells, which target a protein called B7-H3 found in many cancers, shows promise in early tests for treating children's solid tumors, including brain tumors. These CAR T cells are designed to find and attack cancer cells by recognizing specific proteins on them. Early results suggest this method could help treat cancers such as rhabdomyosarcoma, Ewing sarcoma, neuroblastoma, and Wilms tumor. In this trial, participants will receive a combination of B7-H3 CAR T cells with another type of T cell targeting a different cancer protein. This combined approach might enhance effectiveness, potentially leading to improved outcomes for patients. Although detailed results in humans remain limited, early lab studies are encouraging.¹²⁴⁵⁶