CAR-T cells targeting IL-1RAP produced in a closed semiautomatic system are ready for the first phase I clinical investigation in humans

[Can academic structures improve access to CAR-T cells?]

In France, hospital cell therapy units have not been authorised to routinely produce chimeric antigen receptor T lymphocytes (CAR-T cells), which would then be referred to as academic CAR-T cells. CAR-T cells are classified as advanced therapy medicinal products and correspond to genetically modified T lymphocytes ex vivo. The CAR-T cell production process is complex and requires scientific and technical expertise to meet the acceptance criteria of the pharmaceutical quality system. The most commonly used method for genetically modifying T lymphocytes is viral transduction (lentiviral or retroviral), which requires prior access to a batch of good manufacturing practice (GMP) grade viral vector. Because of its cost, this reagent is the main limiting factor for developing CAR-T cells. A CAR-T cell produced by an industrial company is expensive (around €350,000 per injection) and the time taken by the manufacturer to make it available to the clinician can vary from three to five weeks. By meeting the economic and ecological challenges, can academic structures improve access to CAR-T cells? In this article, we present the elements necessary for the feasibility of setting up CAR-T cell production in an academic structure.

Broadening the horizon: potential applications of CAR-T cells beyond current indications

Engineering immune cells to treat hematological malignancies has been a major focus of research since the first resounding successes of CAR-T-cell therapies in B-ALL. Several diseases can now be treated in highly therapy-refractory or relapsed conditions. Currently, a number of CD19- or BCMA-specific CAR-T-cell therapies are approved for acute lymphoblastic leukemia (ALL), diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), multiple myeloma (MM), and follicular lymphoma (FL). The implementation of these therapies has significantly improved patient outcome and survival even in cases with previously very poor prognosis. In this comprehensive review, we present the current state of research, recent innovations, and the applications of CAR-T-cell therapy in a selected group of hematologic malignancies. We focus on B- and T-cell malignancies, including the entities of cutaneous and peripheral T-cell lymphoma (T-ALL, PTCL, CTCL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), classical Hodgkin-Lymphoma (HL), Burkitt-Lymphoma (BL), hairy cell leukemia (HCL), and Waldenström's macroglobulinemia (WM). While these diseases are highly heterogenous, we highlight several similarly used approaches (combination with established therapeutics, target depletion on healthy cells), targets used in multiple diseases (CD30, CD38, TRBC1/2), and unique features that require individualized approaches. Furthermore, we focus on current limitations of CAR-T-cell therapy in individual diseases and entities such as immunocompromising tumor microenvironment (TME), risk of on-target-off-tumor effects, and differences in the occurrence of adverse events. Finally, we present an outlook into novel innovations in CAR-T-cell engineering like the use of artificial intelligence and the future role of CAR-T cells in therapy regimens in everyday clinical practice.

Comparison of two lab-scale protocols for enhanced mRNA-based CAR-T cell generation and functionality

Process development for transferring lab-scale research workflows to automated manufacturing procedures is critical for chimeric antigen receptor (CAR)-T cell therapies. Therefore, the key factor for cell viability, expansion, modification, and functionality is the optimal combination of medium and T cell activator as well as their regulatory compliance for later manufacturing under Good Manufacturing Practice (GMP). In this study, we compared two protocols for CAR-mRNA-modified T cell generation using our current lab-scale process, analyzed all mentioned parameters, and evaluated the protocols' potential for upscaling and process development of mRNA-based CAR-T cell therapies.

RapaCaspase-9-based suicide gene applied to the safety of IL-1RAP CAR-T cells

Even if adoptive cell transfer (ACT) has already shown great clinical efficiency in different types of disease, such as cancer, some adverse events consistently occur, and suicide genes are an interesting system to manage these events. Our team developed a new medical drug candidate, a chimeric antigen receptor (CAR) targeting interleukin-1 receptor accessory protein (IL-1RAP), which needs to be evaluated in clinical trials with a clinically applicable suicide gene system. To prevent side effects and ensure the safety of our candidate, we devised two constructs carrying an inducible suicide gene, RapaCasp9-G or RapaCasp9-A, containing a single-nucleotide polymorphism (rs1052576) affecting the efficiency of endogenous caspase 9. These suicide genes are activated by rapamycin and based on the fusion of human caspase 9 with a modified human FK-binding protein, allowing conditional dimerization. RapaCasp9-G- and RapaCasp9-A-expressing gene-modified T cells (GMTCs) were produced from healthy donors (HDs) and acute myeloid leukemia (AML) donors. The RapaCasp9-G suicide gene demonstrated better efficiency, and we showed its in vitro functionality in different clinically relevant culture conditions. Moreover, as rapamycin is not pharmacologically inert, we also demonstrated its safe use as part of our therapy.

Novel SPEA Superantigen Peptide Agonists and Peptide Agonist-TGFαL3 Conjugate. In Vitro Study of Their Growth-Inhibitory Effects for Targeted Cancer Immunotherapy

Bacterial superantigens (SAgs) are effective T-cell stimulatory molecules that lead to massive cytokine production. Superantigens crosslink between MHC class II molecules on the Antigen Presenting Cells (APC) and TCR on T-cells. This enables them to activate up to 20% of resting T cells, whilst conventional antigen presentation results in the activation of 0.001-0.0001% of the T cell population. These biological properties of superantigens make them attractive for use in immunotherapy. Previous studies have established the effectiveness of superantigens as therapeutic agents. This, however, was achieved with severe side effects due to the high lethality of the native toxins. Our study aims to produce superantigen-based peptides with minimum or no lethality for safer cancer treatment. In previous work, we designed and synthesized twenty overlapping SPEA-based peptides and successfully mapped regions in SPEA superantigen, causing a vasodilatory response. We screened 20 overlapping SPEA-based peptides designed and synthesized to cover the whole SPEA molecule for T-cell activation and tumor-killing ability. In addition, we designed and synthesized tumor-targeted superantigen-based peptides by fusion of TGFαL3 either from the N' or C' terminal of selected SPEA-based peptides with an eight-amino acid flexible linker in between. Our study identified parts of SPEA capable of stimulating human T-cells and producing different cytokines. We also demonstrated that the SPEA-based peptide conjugate binds specifically to cancer cells and can kill this cancer. Peptides induce T-cell activation, and tumor killing might pave the way for safer tumor-targeted superantigens (TTS). We proposed the combination of our new superantigen-based peptide conjugates with other immunotherapy techniques for effective and safer cancer treatment.