Project 1
Development of a chimeric antigen receptor that specifically and selectively recognizes acute myeloid leukemia (AML) blasts
Prof. Dr. med. Marion Subklewe
Medizinische Klinik III, KUM
Prof. Dr. med. Michael von Bergwelt
Medizinische Klinik III, KUM
Prof. Dr. med. Louisa von Baumgarten
Neurochirurgische Klinik, KUM
PD Dr. rer. nat. Thomas Nerreter
Medizinische Klinik II, UKW
Prof. Dr. med. Tobias Feuchtinger
Universitätsklinikum Freiburg
Prof. Dr. med. Michael Hudecek
Medizinische Klinik II, UKW
Prof. Dr. med. Hermann Einsele
Medizinische Klinik II, UKW
Project Summary
Acute myeloid leukemia (AML) is the most common acute leukemia in adults and has been diagnosed worldwide in 150,000 people in 2020 only. Despite an initial curative approach, many patients do not respond or relapse after initial response. As a result, 100,000 people died from AML in the same period [1]. In the relapsed situation, allogenic stem cell transplantation is the only curative treatment, yet this applies to at most 25% of those treated, demonstrating the great medical need for innovative therapies [2]. So far, the development of new immunotherapies, such as chimeric antigen receptor (CAR)-modified T cells, has not been as successful as anticipated. This is due to their level of efficacy or their association with severe toxicity effects.
CAR (chimeric antigen receptors) are synthetic receptors consisting of the fusion of the variable part of an antibody with T cell activating and costimulatory domains [3]. These receptors can be introduced into immune cells, especially T cells, by gene transfer. This allows the target cell the ability to recognize and lyse antigen-positive cells [4]. This procedure has been successfully applied and approved for clinical use against CD19 as an antigen associated with lymphoma and B-cell leukaemia [5]. Our aim is to adapt this technology against AML blasts.
So far, attempts using CAR T cells directed against prominent targets (CD33 o CD123) in AML blasts have not been entirely successful. This is mainly because the presence of the targets on haematopoietic stem cells leads to the depletion of human haematopoiesis [6, 7].
The current literature suggests that leukemia is caused by mutations in different hematopoietic progenitor cells [8]. This implies that AML blasts and their stem cells share many phenotypic similarities with the cells healthy hematopoiesis. Consequently, this leads to a lack of discrimination of AML-targeted therapies and thus, among others, to severe haematological toxicities [9]. Therefore, the urge of finding better targets for AML. Such structures would have the potential to allow immunotherapies in AML and would have a great medical and economic potential.
In preliminary work, we could identify, for the first time antigens with predicted superior selectivity for AML blasts [10]. We developed CAR against these targets and demonstrated superior efficacy and discriminatory capacity in preclinical models. To now advance to clinical development, the parties will establish technologies and a manufacturing process involving GMP materials and media developed by Sirion/Revvity that comply with regulatory requirements, while preserving the previously described properties.
1. Sung, H., et al., Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin, 2021. 71(3): p. 209-249.
2. Shimoni, A., et al., Donor selection for a second allogeneic stem cell transplantation in AML patients relapsing after a first transplant: a study of the Acute Leukemia Working Party of EBMT. Blood Cancer J, 2019. 9(12): p. 88.
3. Tokarew, N., et al., Teaching an old dog new tricks: next-generation CAR T cells. Br J Cancer, 2019. 120(1): p. 26-37.
4. Benmebarek, M.R., et al., Killing Mechanisms of Chimeric Antigen Receptor (CAR) T Cells. Int J Mol Sci, 2019. 20(6).
5. Lesch, S., et al., Determinants of response and resistance to CAR T cell therapy. Semin Cancer Biol, 2020. 65: p. 80-90.
6. Wang, Q.S., et al., Treatment of CD33-directed chimeric antigen receptor-modified T cells in one patient with relapsed and refractory acute myeloid leukemia. Mol Ther, 2015. 23(1): p. 184-91.
7. Yao, S., et al., Donor-Derived CD123-Targeted CAR T Cell Serves as a RIC Regimen for Haploidentical Transplantation in a Patient With FUS-ERG+ AML. Front Oncol, 2019. 9: p. 1358.
8. Khaldoyanidi, S., et al., Immune Biology of Acute Myeloid Leukemia: Implications for Immunotherapy. J Clin Oncol, 2021. 39(5): p. 419-432.
9. Mardiana, S. and S. Gill, CAR T Cells for Acute Myeloid Leukemia: State of the Art and Future Directions. Front Oncol, 2020. 10: p. 697.
10. Gottschlich, A., et al., Single-cell transcriptomic atlas-guided development of CAR-T cells for the treatment of acute myeloid leukemia. Nat Biotechnol, 2023.