Cost of decentralized CAR T-cell production in an academic nonprofit setting.

Chimeric antigen receptor (CAR) T-cell therapy is a promising immunotherapy with high acquisition costs, and it has raised concerns about affordability and sustainability in many countries. Furthermore, the current centralized production paradigm for the T cells is less than satisfactory. Therefore, several countries are exploring alternative T-cell production modes. Our study is based on the T-cell production experience in a nonprofit setting in Germany. We first identified the work steps and main activities in the production process. Then we determined the fixed costs and variable costs. Main cost components included personnel and technician salaries, expenditure on equipment, a clean room, as well as production materials. All costs were calculated in 2018 euros and converted into U.S. dollars. For a clean room with one machine for closed and automated manufacturing installed, annual fixed costs summed up to approximately €438 098 ($584 131). The variable cost per production was roughly €34 798 ($46 397). At the maximum capacity of one machine, total cost per product would be close to €60 000 ($78 849). As shown in the scenario analysis, if three machines were to be installed in the clean room, per production cost could be as low as €45 000 (roughly $59905). If a cheaper alternative to lentivirus was used, per production total cost could be further reduced to approximately €33 000 (roughly $44309). Decentralized T-cell production might be a less costly and more efficient alternative to the current centralized production mode that requires a high acquisition cost.

Point-Of-Care CAR T-Cell Production (ARI-0001) Using a Closed Semi-automatic Bioreactor: Experience From an Academic Phase I Clinical Trial.

Development of semi-automated devices that can reduce the hands-on time and standardize the production of clinical-grade CAR T-cells, such as CliniMACS Prodigy from Miltenyi, is key to facilitate the development of CAR T-cell therapies, especially in academic institutions. However, the feasibility of manufacturing CAR T-cell products from heavily pre-treated patients with this system has not been demonstrated yet. Here we report and characterize the production of 28 CAR T-cell products in the context of a phase I clinical trial for CD19+ B-cell malignancies (NCT03144583). The system includes CD4-CD8 cell selection, lentiviral transduction and T-cell expansion using IL-7/IL-15. Twenty-seven out of 28 CAR T-cell products manufactured met the full list of specifications and were considered valid products. Ex vivo cell expansion lasted an average of 8.5 days and had a mean transduction rate of 30.6 ± 13.44%. All products obtained presented cytotoxic activity against CD19+ cells and were proficient in the secretion of pro-inflammatory cytokines. Expansion kinetics was slower in patient's cells compared to healthy donor's cells. However, product potency was comparable. CAR T-cell subset phenotype was highly variable among patients and largely determined by the initial product. TCM and TEM were the predominant T-cell phenotypes obtained. 38.7% of CAR T-cells obtained presented a TN or TCM phenotype, in average, which are the subsets capable of establishing a long-lasting T-cell memory in patients. An in-depth analysis to identify individual factors contributing to the optimal T-cell phenotype revealed that ex vivo cell expansion leads to reduced numbers of TN, TSCM, and TEFF cells, while TCM cells increase, both due to cell expansion and CAR-expression. Overall, our results show for the first time that clinical-grade production of CAR T-cells for heavily pre-treated patients using CliniMACS Prodigy system is feasible, and that the obtained products meet the current quality standards of the field. Reduced ex vivo expansion may yield CAR T-cell products with increased persistence in vivo.

Targeting Cancer Stem Cells by Genetically Engineered Chimeric Antigen Receptor T Cells.

The term cancer stem cell (CSC) starts 25 years ago with the evidence that CSC is a subpopulation of tumor cells that have renewal ability and can differentiate into several distinct linages. Therefore, CSCs play crucial role in the initiation and the maintenance of cancer. Moreover, it has been proposed throughout several studies that CSCs are behind the failure of the conventional chemo-/radiotherapy as well as cancer recurrence due to their ability to resist the therapy and their ability to re-regenerate. Thus, the need for targeted therapy to eliminate CSCs is crucial; for that reason, chimeric antigen receptor (CAR) T cells has currently been in use with high rate of success in leukemia and, to some degree, in patients with solid tumors. This review outlines the most common CSC populations and their common markers, in particular CD133, CD90, EpCAM, CD44, ALDH, and EGFRVIII, the interaction between CSCs and the immune system, CAR T cell genetic engineering and signaling, CAR T cells in targeting CSCs, and the barriers in using CAR T cells as immunotherapy to treat solid cancers.