CAR-T cell therapy has shown remarkable promise in treating B-cell malignancies, which has sparked optimism about its potential to treat other types of cancer as well. Nevertheless, the Expectations of CAR-T cell therapy in solid tumors and non-B cell hematologic malignancies have not been met. Furthermore, safety concerns regarding the use of viral vectors and the current personalized production process are other bottlenecks that limit its widespread use. In recent years the use of gene editing technology in CAR-T cell therapy has opened a new way to unleash the latent potentials of CAR-T cell therapy and lessen its associated challenges. Moreover, gene editing tools have paved the way to manufacturing CAR-T cells in a fully non-viral approach as well as providing a universal, off-the-shelf product. Despite all the advantages of gene editing strategies, the off-target activity of classical gene editing tools (ZFNs, TALENs, and CRISPR/Cas9) remains a major concern. Accordingly, several efforts have been made in recent years to reduce their off-target activity and genotoxicity, leading to the introduction of advanced gene editing tools with an improved safety profile. In this review, we begin by examining advanced gene editing tools, providing an overview of how these technologies are currently being applied in clinical trials of CAR-T cell therapies. Following this, we explore various gene editing strategies aimed at enhancing the safety and efficacy of CAR-T cell therapy.

Although CAR-T cell therapy has emerged as a game-changer in cancer immunotherapy several bottlenecks limit its widespread use as a front-line therapy. Current protocols for the production of CAR-T cells rely mainly on the use of lentiviral/retroviral vectors. Nevertheless, according to the safety concerns around the use of viral vectors, there are several regulatory hurdles to their clinical use. Large-scale production of viral vectors under \"Current Good Manufacturing Practice\" (cGMP) involves rigorous quality control assessments and regulatory requirements that impose exorbitant costs on suppliers and as a result, lead to a significant increase in the cost of treatment. Pursuing an efficient non-viral method for genetic modification of immune cells is a hot topic in cell-based gene therapy. This study aims to investigate the current state-of-the-art in non-viral methods of CAR-T cell manufacturing. In the first part of this study, after reviewing the advantages and disadvantages of the clinical use of viral vectors, different non-viral vectors and the path of their clinical translation are discussed. These vectors include transposons (sleeping beauty, piggyBac, Tol2, and Tc Buster), programmable nucleases (ZFNs, TALENs, and CRISPR/Cas9), mRNA, plasmids, minicircles, and nanoplasmids. Afterward, various methods for efficient delivery of non-viral vectors into the cells are reviewed.

Multiple myeloma (MM) is a hematologic malignancy defined by the clonal proliferation of transformed plasma cells. Despite tremendous advances in the treatment paradigm of MM, a cure remains elusive for most patients. Although long-term disease control can be achieved in a very large number of patients, the acquisition of tumor resistance leads to disease relapse, especially in patients with triple-class refractory MM (defined as resistance to immunomodulatory agents, proteosome inhibitors, and monoclonal antibodies). There is an unmet need for effective treatment options in these patients. Chimeric antigen receptor (CAR) T-cell therapy is a novel approach that has demonstrated promising efficacy in the treatment of relapsed, refractory MM (RRMM). These genetically modified cellular therapies have demonstrated deep and durable remissions in other B-cell malignancies, and current efforts aim to achieve similar results in patients with RRMM. Early studies have demonstrated remarkable response rates with CAR T-cell therapy in RRMM; however, durable responses with CAR T-cell therapies in myeloma have yet to be realized. In this comprehensive review, the authors describe the development of CAR T-cell therapies in myeloma, the outcomes of notable clinical trials, the toxicities and limitations of CAR T-cell therapies, and the strategies to overcome therapeutic challenges of CAR T cells in the hope of achieving a cure for multiple myeloma.

Despite favorable results of CAR T-cell therapy for relapsed/refractory large B-cell lymphoma (R/R LBCL), several challenges remain, including incomplete response, immune-mediated toxicity, and antigen-loss relapse. We delineated the relative clinical benefit of the novel approaches compared to the currently approved CAR T-cell therapies. In the absence of head-to-head comparisons and randomized controlled trials, we performed Matching Adjusted Indirect Comparisons to quantify the relative efficacy and safety of experimental CARs against Axicabtagene ciloleucel (Yescarta), the first FDA-approved CAR. A total of 182 R/R LBCL patients from 15 clinical trials with individual patient data (IPD) were pooled into eight populations by their CAR T-cell constructs and +/- ASCT status. The study endpoints were Progression-Free Survival (PFS), grade ≥ 3 cytokine release syndrome (CRS), and grade ≥ 3 neurotoxicity (NT). Tandem CD19.CD20.4-1BBζ CARs indicated favorable efficacy and safety, whereas the co-infusion of CD19 & CD20 with 4-1BBζ showed no clinical benefit compared to Yescarta. Third generation CD19. CD28. 4-1BBζ, and sequential administration of autologous stem cell transplantation (ASCT) and CD19. CARs presented statistically insignificant yet improved PFS and safety except for ASCT combined intervention which had suggestively higher NT risk than Yescarta. CARs with modified co-stimulatory domains to reduce toxicity (Hu19. CD8.28Zζ and CD19. BBz.86ζ) presented remarkable safety with no severe adverse events; however, both presented worse PFS than Yescarta. Third-generation CARs demonstrated statistically significantly lower NT than Yescarta. CD20. 4-1BBζ data suggested targeting CD20 antigen alone lacks clinical or safety benefit compared to Yescarta. Further comparisons with other FDA-approved CARs are needed.

UNASSIGNED: Multiple myeloma (MM) is a malignant tumor originating from plasma cells in the bone marrow. The existing treatment methods can prolong the survival time of patients, but they still face the problems of myeloma relapse and refractory disease. Chimeric antigen receptor (CAR)-T cell therapy is a new cellular immunotherapy that can target and recognize antigens and kill tumor cells but the efficacy and safety data varied in different studies. We performed this systematic review and meta-analysis to understand its efficacy and safety.
UNASSIGNED: Literature published from January 2015 to November 2021 was obtained by searching the keywords \"CAR-T\", \"CAR-T Cell\", and \"Multiple Myeloma\" by computer using the Embase, PubMed, Web of Science, and Cochrane library databases according to the PICOS (Participants, Interventions, Comparisons, Outcomes, Study type) criteria. The quality of the literature was assessed by the Joanna Briggs Institute (JBI) Critical Appraisal Tool for prevalence studies. The complete response rate, the incidence of cytokine release syndrome (CRS) above grade 3, and the overall incidence of adverse reactions were used as the outcome indicators. The pooled rates were performed and analyzed using the R language toolkit.
UNASSIGNED: A total of 10 studies including 353 study cases were included. Meta-analysis showed that the pooled complete response rate of CAR-T therapy in the treatment of MM was 0.55, 95% confidence interval (CI): (0.50, 0.60), the pooled incidence of CRS was 0.55, 95% CI: (0.50, 0.60), and the pooled incidence of serious adverse reactions was 0.92, 95% CI: (0.88, 0.95). Subgroup analysis was performed based on antigen types or costimulatory molecules, and there was no significant difference in the efficacy of CAR-T and the incidence of CRS between the two subgroups (P>0.05).
UNASSIGNED: As a new immunotherapy strategy with great potential, CAR-T has a significant effect in the treatment of MM, but its safety needs to be further improved. The types of costimulatory molecules and CAR-T antigens can affect its efficacy and safety.