Accelerating clinical-scale production of BCMA CAR T cells with defined maturation stages

Jara J Joedicke; Ulrich Großkinsky; Kerstin Gerlach; Annette Künkele; Uta E Höpken; Armin Rehm

doi:10.1016/j.omtm.2021.12.005

Accelerating clinical-scale production of BCMA CAR T cells with defined maturation stages

Mol Ther Methods Clin Dev. 2021 Dec 25:24:181-198. doi: 10.1016/j.omtm.2021.12.005. eCollection 2022 Mar 10.

Authors

Jara J Joedicke¹, Ulrich Großkinsky¹, Kerstin Gerlach¹, Annette Künkele^{2

3}, Uta E Höpken⁴, Armin Rehm¹

Affiliations

¹ Department of Translational Tumorimmunology, Max-Delbrück-Center for Molecular Medicine, 13125 Berlin, Germany.
² Charité-University Medicine, Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Pediatric Oncology and Hematology, 13353 Berlin, Germany.
³ Charité-University Medicine, Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Stem Cell Facility, Department of Hematology, Oncology and Tumorimmunology, 13353 Berlin, Germany.
⁴ Department of Microenvironmental Regulation in Autoimmunity and Cancer, Max-Delbrück-Center for Molecular Medicine, 13125 Berlin, Germany.

Abstract

The advent of CAR T cells targeting CD19 or BCMA on B cell neoplasm demonstrated remarkable efficacy, but rapid relapses and primary refractoriness remains challenging. A leading cause of CAR T cell failure is their lack of expansion and limited persistence. Long-lived, self-renewing multipotent T memory stem cells (T_SCM) and T central memory cells (T_CM) likely sustain superior tumor regression, but their low frequencies in blood from cancer patients impose a major hurdle for clinical CAR T production. We designed a clinically compliant protocol for generating BCMA CAR T cells starting with increased T_SCM/T_CM cell input. A CliniMACS Prodigy process was combined with flow cytometry-based enrichment of CD62L⁺CD95⁺ T cells. Although starting with only 15% of standard T cell input, the selected T_SCM/T_CM material was efficiently activated and transduced with a BCMA CAR-encoding retrovirus. Cultivation in the presence of IL-7/IL-15 enabled the harvest of CAR T cells containing an increased CD4⁺ T_SCM fraction and 70% T_SCM cells amongst CD8⁺. Strong cell proliferation yielded cell numbers sufficient for clinical application, while effector functions were maintained. Together, adaptation of a standard CliniMACS Prodigy protocol to low input numbers resulted in efficient retroviral transduction with a high CAR T cell yield.

Keywords: B cell maturation antigen; GMP manufacturing; Prodigy bioreactor; T central memory cell; T memory stem cell; adoptive T cell therapy; chimeric antigen receptor T cell; flow cytometry cell sorting; retrovirus.