CD6 Chimeric Antigen Receptor T Regulatory Cells(City of Hope)

This phase I trial tests the safety, side effects, and best dose of allogeneic CD6 chimeric antigen receptor T regulatory cells (CD6-CAR Tregs) in treating patients who have chronic graft versus host disease (cGVHD) after an allogeneic hematopoietic cell transplantation (HCT). An allogeneic HCT is an established treatment for benign or malignant blood and marrow conditions where healthy stem cells from a donor are infused into a patient to help the patient's bone marrow make more healthy cells and platelets. GVHD is a systemic disorder that occurs when the graft's immune cells recognize the host as foreign and attack the recipient's body cells. "Graft" refers to transplanted, or donated tissues, and "host" refers to the tissues of the recipient. It is a common complication after allogeneic HCT. The onset of cGVHD is usually within three years of transplantation and has some features of autoimmune diseases. A strategy that minimizes the incidence and severity of cGVHD, without other adverse effects, is needed to improve survival after allogeneic HCT. T regulatory cells are critical for controlling autoimmunity and maintaining immune homeostasis. Patients with active cGVHD have reduced numbers of T regulatory cells compared to patients without GVHD, suggesting that restoration of T regulatory cells in patients with active cGCHD is impaired and insufficient numbers may contribute to cGVHD. Therefore, therapies that augment numbers and function of T regulatory cells may promote tolerance and control of cGVHD. CAR T-cell therapy is a type of treatment in which T cells (a type of immune system cell) are taken from the blood and changed in the laboratory. The gene for a special receptor that binds to a certain protein, CD6, on the patient's cells is added to the T cells in the laboratory. The special receptor is called a chimeric antigen receptor (CAR). Large numbers of the CAR T cells are grown in the laboratory and given to the patient by infusion. CD6-CAR Tregs combines the CD6-targeted anti-inflammatory response with the immune regulatory properties of T regulatory cells which could generate a more potent and stable T regulatory cell population to promote immune tolerance and long-term disease control in cGVHD.