CD70-directed CAR T-cell therapy for the treatment of relapsed/refractory pediatric AML
Stephen Gottschalk
MDSt. Jude Children's Research Hospital
Project Term: July 1, 2023 - June 30, 2026
In this project, we will test an innovative therapy called CAR T-cell therapy for children with a type of cancer called AML. In the laboratory, we have identified and developed a powerful CAR T-cell therapy that targets a protein called CD70 on AML cells. We propose to now develop a clinical trial in which we will study the effects of this CD70.CAR T-cell therapy in children with AML.
Acute myeloid leukemia (AML) is the second most common blood cancer in children. Despite the use of very intense and toxic chemotherapy, which can cause significant side effects, only about 55% of children with AML survive. There is also a high chance of the disease coming back and, in that case, less than 1/3rd of those children will survive. Therefore, new treatments that do not use intense chemotherapies are urgently needed. Normal (healthy) T cells are a type of immune system cell that can fight infection and cancer in the body. Our group focuses on using the patient’s own T cells and modifies them in the lab to recognize and kill leukemia cells. These types of T-cells are called CAR T cells and they work by targeting proteins that are present on the surface of leukemia cells. These types of CAR T-cells have worked very well in patients with Acute Lymphoblastic Leukemia (ALL). For patients with AML, CAR T-cell therapy has been challenging. This is because it has been difficult to find a protein that is present on leukemia cells but not on normal cells. We have identified CD70 as a protein that is expressed by many AML cells. We tested many different CD70.CAR T-cells in the laboratory and found one that worked the best. This powerful CD70.CAR T-cell was able to kill AML cells in the laboratory. Unlike most other CAR T-cell therapies for AML that are currently being tested, our CD70.CAR T cells have the potential to kill cancer cells without harming normal blood forming cells. We are now requesting funding to be able to take these findings from the laboratory to a clinical trial. We anticipate that we will be able to start this trial within the next year. This potentially life-saving therapy will be tested in children with AML that is difficult to treat or has come back. As part of the clinical trial, we will obtain samples from the patients so that we can better understand how the CD70.CAR T-cells are growing in the patient’s body and how they are attacking the AML cells. We will perform these studies with experts in the field who know how to study CAR T-cells and AML cells. These studies will help us make the trial better in the future. We will perform this clinical trial in collaboration with Texas Children’s Hospital (TCH) so we can test this approach in more than one center. TCH is also a very large children’s cancer hospital and has a lot of experience in running clinical trials for CAR T-cells and we do not anticipate any difficulties. If our clinical trial successful in children with AML, this CD70.CAR T-cell therapy can also be used in adults with AML and in both, children and adults with lymphomas. Therefore, this project has the potential to have widespread impact.