Targeting B Cell Maturation Antigen (BCMA) in Multiple Myeloma: Potential Uses of BCMA-Based Immunotherapy

Bispecific antibody and chimeric antigen receptor (CAR) modified T-cell in the treatment of multiple myeloma: Where do we stand today?

Although the prognosis of patients with multiple myeloma (MM) has been significantly improved by the introduction of proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies, MM is still considered an incurable disease in the vast majority of the patients. In recent years, T-cell based immunotherapy represents a novel treatment strategy for relapsed/refractory (RR) MM. So far, chimeric antigen receptor (CAR) modified T-cells and bispecific T-cell engaging antibodies (bsAb) have shown promising anti-MM efficacy and manageable safety profile within clinical trials, and B-cell maturation antigen (BCMA) is the most commonly used immune target for T-cell based immunotherapies in MM. To date, several CAR T-cell and bsAb products have already been approved for the treatment of RRMM, leading to a paradigm shift in the MM therapy and providing a potential curative option. In this review, we provide a summary of mechanisms of action, immune targets, selected clinical data, resistance mechanisms and therapy sequencing of CAR T-cell and bsAb in MM.

Comparison of CAR T-cell and bispecific antibody as third-line or later-line treatments for multiple myeloma: a meta-analysis

BACKGROUND

CAR-T-cell therapy and bispecific antibody have revolutionized the treatment landscape for multiple myeloma. However, there is currently a lack of studies comparing the efficacy and safety of these two approaches. This meta-analysis assesses the efficacy and safety of B-cell maturation antigen (BCMA)-directed CAR-T-cell therapies and BCMA×CD3 bispecific antibodies as third-line or later interventions for relapsed/refractory multiple myeloma (RRMM).

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane databases up to May 31, 2024, identifying 11 eligible studies encompassing 1269 participants. Random-effects models evaluated the primary (complete response (CR) rate) and secondary (overall response rate (ORR)) outcomes, while meta-regression analyses adjusted for relevant covariates.

RESULTS

CAR-T-cell therapy achieved significantly higher pooled CR rate (0.54 (95% CI 0.42-0.69) vs bispecific antibodies 0.35 (0.30-0.41), p<0.01) and pooled ORR (0.83 (0.76-0.90) vs 0.65 (0.59-0.71), p<0.01). However, CAR-T therapy had a higher incidence of adverse events, particularly cytokine release syndrome (CRS 0.83 (0.70-0.97) vs bispecific antibodies 0.59 (0.43-0.74), p<0.05). Severe CRS (grade ≥3) occurred at a rate of 0.07 (0.03-0.14) in the CAR-T cell group, contrasting with a negligible rate of 0.01 (0.00-0.02) in the bispecific antibody group (p<0.01). Hematologic adverse events, including neutropenia (grade ≥3; 0.88 (0.81-0.95) vs 0.48 (0.30-0.67), p<0.01) and anemia (grade≥3; 0.55 (0.47-0.62) vs 0.34 (0.28 to 0.40), p<0.01), were also more frequent in the CAR-T-cell group. Furthermore, differences in efficacy were observed among various CAR-T products, with ciltacabtagene autoleucel showing greater efficacy in CR rate (0.77 (0.71-0.84) vs 0.37 (0.32-0.41), p<0.01) and ORR (0.91 (0.83-0.99) vs 0.73 (0.68-0.77), p<0.01) compared with idecabtagene vicleucel.

CONCLUSION

CAR-T-cell therapy demonstrated superior CR rates compared with bispecific antibodies, although with an increase in severe adverse events.

Preclinical delayed toxicity studies of BCMA CAR T-cell injection in B-NDG mice with multiple myeloma

Purpose

Based on the efficacy data from the previous study of B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell injection, we further examined the delayed toxicity for 8 weeks after a single dose of BCMA CAR T-cell injection to observe possible toxic reactions.

Methods

B-NDG mice transplanted with multiple myeloma (MM) cells were given a single dose of BCMA CAR T-cell injection at two dosages or human normal T cells and then subjected to examinations including clinical signs, weight and food intake measurements, haematology, blood biochemical analysis, cytokine assay, T-lymphocyte subpopulation quantification and histopathology on days 28 and 56 after dosing. In addition, quantitative polymerase chain reaction (qPCR) was used to quantify DNA fragments in different tissues to assess the tissue distribution of CAR and provide a basis for its preclinical safety evaluation and clinical dosing.

Results

In the delayed toxicity study, no mortality or significant toxic effects such as reductions in food intake, body weight, relevant biochemical parameters and target organ weights were observed in the BCMA CAR T-cell-treated groups. Compared to the model group, restorative changes in clinical signs and clinicopathology indicating therapeutic effects were seen in the BCMA CAR T-cell-treated groups. Human-derived cytokines interleukin-2 (IL-2), IL-4, IL-6, IL-12, IL-10, tumor necrosis factor α (TNF-α), and interferon-γ (IFN-γ) could be detected in all cancer cell-bearing mice by cytokine level measurement. IFN-γ levels showed a geometric increase due to the graft versus host disease (GVHD) response induced in the mice, while the levels of the other cytokines did not show significant changes. Histopathological examination indicated that the BCMA CAR T-cell treatment groups showed mixed cellular infiltration of human-derived T cells, cancer cells, and inflammatory cells in several target organs including the liver, spleen, lung, and kidney, and some of them showed mild tissue damage, but the number of the animals and the severity of damage were significantly less than those of the T-cell control group as well as the model group. The results of the tissue distribution study showed that BCMA CAR T cells were mainly concentrated in the kidney, lung, bone marrow and the related immune organs/tissues, and the distribution of BCMA CAR T cells was highly consistent with that of MM cells, suggesting that BCMA CAR T cells could follow the cancer cells during metastatic targeting of the tissues.

Conclusions

The present study demonstrated a low toxicity of BCMA CAR T-cell injection, with manageable side effects and good anticancer activity and without observable adverse effects. This study provides data to support future clinical studies of BCMA CAR T-cell injection for MM.

Fast and furious: Changing gears on the road to cure with chimeric antigen receptor T cells in multiple myeloma

Based on the pivotal KarMMa-1 and CARTITUDE-1 studies, Idecabtagene vicleucel (Ide-cel) and Ciltacabtagene autoleucel (Cilta-cel) have been approved to treat multiple myeloma patients, who have been exposed to at least 1 proteasome inhibitor, immunomodulatory drug and anti-CD38 antibody after 4 or 3 lines of therapy, respectively. The unprecedented rates of deep and long-lasting remissions have been meanwhile confirmed in multiple real-world analyses and more recently, the KarMMa-3 and CARTITUDE-4 studies lead to the approval in earlier lines of therapy. It is currently believed that ultimately all patients with relapsed/refractory multiple myeloma experience relapse after anti-BCMA CAR T-cell therapies. There is a plethora of CAR T-cell therapies targeting novel antigens, with the aim to overcome current CAR T-cell resistance. In this review, we will summarize current evidence of novel antigens and their clinical potential. Together with current CAR T-cell therapy and T-cell engagers, these approaches might lead us to the next frontier in multiple myeloma: total immunotherapy and the road to chemotherapy-free cure.

Targeting B-cell maturation antigen for treatment and monitoring of relapsed/refractory multiple myeloma patients: a comprehensive review

Despite major therapeutic advancements in recent years, multiple myeloma (MM) remains an incurable disease with nearly all patients experiencing relapsed and refractory disease over the course of treatment. Extending the duration and durability of clinical responses will necessitate the development of therapeutics with novel targets that are capable of robustly and specifically eliminating myeloma cells. B-cell maturation antigen (BCMA) is a membrane-bound protein expressed predominantly on malignant plasma cells and has recently been the target of several novel therapeutics to treat MM patients. This review will focus on recently approved and currently in development agents that target this protein, including bispecific antibodies, antibody-drug conjugates, and chimeric antigen receptor T-cell therapies. In addition, this protein also serves as a novel serum biomarker to predict outcomes and monitor disease status for MM patients; the studies demonstrating this use of BCMA will be discussed in detail.

Recent updates on allogeneic CAR-T cells in hematological malignancies

CAR-T cell therapy is known as an effective therapy in patients with hematological malignancies. Since 2017, several autologous CAR-T cell (auto-CAR-T) drugs have been approved by the US Food and Drug Administration (FDA) for the treatment of some kinds of relapsed/refractory hematological malignancies. However, some patients fail to respond to these drugs due to high manufacturing time, batch-to-batch variation, poor quality and insufficient quantity of primary T cells, and their insufficient expansion and function. CAR-T cells prepared from allogeneic sources (allo-CAR-Ts) can be an alternative option to overcome these obstacles. Recently, several allo-CAR-Ts have entered into the early clinical trials. Despite their promising preclinical and clinical results, there are two main barriers, including graft-versus-host disease (GvHD) and allo-rejection that may decline the safety and efficacy of allo-CAR-Ts in the clinic. The successful development of these products depends on the starter cell source, the gene editing method, and the ability to escape immune rejection and prevent GvHD. Here, we summarize the gene editing technologies and the potential of various cell sources for developing allo-CAR-Ts and highlight their advantages for the treatment of hematological malignancies. We also describe preclinical and clinical data focusing on allo-CAR-T therapy in blood malignancies and discuss challenges and future perspectives of allo-CAR-Ts for therapeutic applications.

Telitacicept: A novel horizon in targeting autoimmunity and rheumatic diseases

BLyS and APRIL have the capability to bind to B cells within the body, allowing these cells to evade elimination when they should naturally be removed. While BLyS primarily plays a role in B cell development and maturation, APRIL is linked to B cell activation and the secretion of antibodies. Thus, in theory, inhibiting BLyS or APRIL could diminish the population of aberrant B cells that contribute to SLE and reduce disease activity in patients. Telitacicept functions by binding to and neutralizing the activities of both BLyS and APRIL, thus hindering the maturation and survival of plasma cells and fully developed B cells. The design of telitacicept is distinctive; it is not a monoclonal antibody but a TACI-Fc fusion protein generated through recombinant DNA technology. This fusion involves merging gene segments of the TACI protein, which can target BLyS/APRIL simultaneously, with the Fc gene segment of the human IgG protein. The TACI-Fc fusion protein exhibits the combined characteristics of both proteins. Currently utilized for autoimmune disease treatment, telitacicept is undergoing clinical investigations globally to assess its efficacy in managing various autoimmune conditions. This review consolidates information on the mechanistic actions, dosing regimens, pharmacokinetics, efficacy, and safety profile of telitacicept-a dual-targeted biological agent. It integrates findings from prior experiments and pharmacokinetic analyses in the treatment of RA and SLE, striving to offer a comprehensive overview of telitacicept's research advancements.

Chimeric antigen receptor T-cells: a review on current status and future directions for relapsed/refractory multiple myeloma

Although multiple myeloma is an incurable disease, the past decade has witnessed significant improvement in patient outcomes. This was brought about by the development of T-cell redirection therapies such as chimeric antigen receptor (CAR) T-cells, which can leverage the natural ability of the immune system to fight myeloma cells. The approval of the B-cell maturation antigen (BCMA)-directed CAR T, idecabtagene vicleucel (ide-cel), and ciltacabtagene autoleucel (cilta-cel) has resulted in a paradigm shift in the treatment of relapsed/refractory multiple myeloma. Overall response rates ranging from 73 to 97% are currently achievable. However, the limitations of KarMMa-1 and CARTITUDE-1 studies spurred the generation of real-world data to provide some insights into the effectiveness of ide-cel and cilta-cel among patients who were excluded from clinical trials, particularly those who received prior BCMA-targeted or other T-cell redirection therapies. Despite their unprecedented clinical efficacy in heavily pretreated patients, responses to CAR T remain non-durable. Although the underlying mechanisms of resistance to these agents haven't been fully elucidated, studies have suggested that resistance patterns could be multifaceted, implicating T-cell exhaustion and tumor intrinsic mechanisms such as BCMA target loss, upregulation of gamma-secretase, and others. Herein, we provide a succinct overview of the development of CAR T-cells, manufacturing process, and associated toxicities/complications. In this review, we also recapitulate the existing literature pertaining MM CAR-T as well as emerging data from some of the ongoing clinical trials designed to mitigate the shortcomings of these agents, and improve the clinical efficacy of CAR T, especially in the relapsed/refractory setting.

Anti-BCMA CAR-T cell-based therapies and bispecific antibodies in the immunotherapy era: are we ready for this?

INTRODUCTION

Therapeutic strategies against multiple myeloma (MM) have evolved dramatically in recent decades, with unprecedent results in the treatment landscape, culminating in the recent incorporation of novel agents in the anti-myeloma armamentarium.

AREAS COVERED

BCMA represents one of the most promising targets in MM and currently available immune approaches, either approved or under active investigation, are clearly showing their greater potential over standard regimens. In this context, immunotherapies based on chimeric antigen receptor (CAR)-engineered T-cells and bispecific antibodies (BsAbs) have taken center stage, being the ones that are yielding the most promising results in clinical trials. This review focuses on the current landscape of BsAbs and CAR-T, summarizing the latest advances and possible future developments.

EXPERT OPINION

CAR-T and BsAbs anti-BCMA strategies represent breakthrough therapies against MM. However, their inclusion in clinical practice is almost feared, due to the associated limitations, some of which have been addressed here. Meanwhile, all the efforts should be focused on individualizing and choosing the most suitable candidates for each treatment and to understand how to combine, or sequence, these therapies to improve efficacy and minimize toxicity, especially for those patients with limited available treatment options.

Integrating machine learning algorithms and multiple immunohistochemistry validation to unveil novel diagnostic markers based on costimulatory molecules for predicting immune microenvironment status in triple-negative breast cancer

Introduction

Costimulatory molecules are putative novel targets or potential additions to current available immunotherapy, but their expression patterns and clinical value in triple-negative breast cancer (TNBC) are to be clarified.

Methods

The gene expression profiles datasets of TNBC patients were obtained from The Cancer Genome Atlas and the Gene Expression Omnibus databases. Diagnostic biomarkers for stratifying individualized tumor immune microenvironment (TIME) were identified using the Least Absolute Shrinkage and Selection Operator (LASSO) and Support Vector Machine-Recursive Feature Elimination (SVM-RFE) algorithms. Additionally, we explored their associations with response to immunotherapy via the multiplex immunohistochemistry (mIHC).

Results

A total of 60 costimulatory molecule genes (CMGs) were obtained, and we determined two different TIME subclasses ("hot" and "cold") through the K-means clustering method. The "hot" tumors presented a higher infiltration of activated immune cells, i.e., CD4 memory-activated T cells, resting NK cells, M1 macrophages, and CD8 T cells, thereby enriched in the B cell and T cell receptor signaling pathways. LASSO and SVM-RFE algorithms identified three CMGs (CD86, TNFRSF17 and TNFRSF1B) as diagnostic biomarkers. Following, a novel diagnostic nomogram was constructed for predicting individualized TIME status and was validated with good predictive accuracy in TCGA, GSE76250 and GSE58812 databases. Further mIHC conformed that TNBC patients with high CD86, TNFRSF17 and TNFRSF1B levels tended to respond to immunotherapy.

Conclusion

This study supplemented evidence about the value of CMGs in TNBC. In addition, CD86, TNFRSF17 and TNFRSF1B were found as potential biomarkers, significantly promoting TNBC patient selection for immunotherapeutic guidance.

Current status of bispecific antibodies and CAR-T therapies in multiple myeloma

Multiple myeloma (MM), a malignancy of plasma cells, is an incurable disease that is characterized by the neoplastic proliferation of plasma cells leading to extensive skeletal destruction. This includes osteolytic lesions, osteopenia, and pathologic fractures. MM is clinically manifested through bone pain, renal insufficiency, hypercalcemia, anemia, and recurrent infections. Its prevalence and the need for effective treatment underscore the importance of this research. Recent advancements in MM therapy have been significant, particularly with the integration of daratumumab into first-line treatments. The use of daratumumab in regimens such as DRD (Daratumumab, Revlimid, Dexamethasone) and D-RVd (Daratumumab, Lenalidomide, Bortezomib, Dexamethasone) represents a paradigm shift in the treatment landscape. GRIFFIN and CASSIOPEIA trials have highlighted the efficacy of these regimens, particularly in prolonging progression-free survival and deepening patient responses. The shift from older regimens like MPV (Melphalan, Prednisone, Velcade) to more effective ones like DRD and RVD has been pivotal in treatment strategies. This review also focuses on the potential of Chimeric Antigen Receptor T-cell therapy and bispecific antibodies in MM. CAR-T therapy, which has shown success in other hematological malignancies, is being explored for its ability to specifically target MM cells. The latest clinical trials and research findings are analyzed to evaluate the efficacy and challenges of CAR-T therapy in MM. Additionally, the role of bispecific antibodies, which are designed to bind both cancer cells and T cells, is explored. These antibodies offer a unique mechanism that could complement the effects of CAR-T therapy.

Remineralization Rate of Lytic Lesions of the Spine in Multiple Myeloma Patients Undergoing Radiation Therapy

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

In general, Multiple Myeloma (MM) patients are treated with systemic therapy including chemotherapy. Radiation therapy can have an important supportive role in the palliative management of MM-related osteolytic lesions. Our study aims to investigate the degree of radiation-induced remineralization in MM patients to gain a better understanding of its potential impact on bone mineral density and, consequently, fracture prevention. Our primary outcome measure was percent change in bone mineral density measured in Hounsfield Units (Δ% HU) between pre- and post-radiation measurements, compared to non-targeted vertebrae.

METHODS

We included 119 patients with MM who underwent radiotherapy of the spine between January 2010 and June 2021 and who had a CT scan of the spine at baseline and between 3-24 months after radiation. A linear mixed effect model tested any differences in remineralization rate per month (βdifference) between targeted and non-targeted vertebrae.

RESULTS

Analyses of CT scans yielded 565 unique vertebrae (366 targeted and 199 non-targeted vertebrae). In both targeted and non-targeted vertebrae, there was an increase in bone density per month (βoverall = .04; P = .002) with the largest effect being between 9-18 months post-radiation. Radiation did not cause a greater increase in bone density per month compared to non-targeted vertebrae (βdifference = .67; P = .118).

CONCLUSION

Our results demonstrate that following radiation, bone density increased over time for both targeted and non-targeted vertebrae. However, no conclusive evidence was found that targeted vertebrae have a higher remineralization rate than non-targeted vertebrae in patients with MM.

An Exploratory Approach of Clinically Useful Biomarkers of Cvid by Logistic Regression

Despite advancements in genetic and functional studies, the timely diagnosis of common variable immunodeficiency (CVID) remains a significant challenge. This exploratory study was designed to assess the diagnostic performance of a novel panel of biomarkers for CVID, incorporating the sum of κ+λ light chains, soluble B-cell maturation antigen (sBCMA) levels, switched memory B cells (smB) and the VISUAL score. Comparative analyses utilizing logistic regression were performed against established gold-standard tests, specifically antibody responses. Our research encompassed 88 subjects, comprising 27 CVID, 23 selective IgA deficiency (SIgAD), 20 secondary immunodeficiency (SID) patients and 18 healthy controls. We established the diagnostic accuracy of sBCMA and the sum κ+λ, achieving sensitivity (Se) and specificity (Spe) of 89% and 89%, and 90% and 99%, respectively. Importantly, sBCMA showed strong correlations with all evaluated biomarkers (sum κ+λ, smB cell and VISUAL), whereas the sum κ+λ was uniquely independent from smB cells or VISUAL, suggesting its additional diagnostic value. Through a multivariate tree decision model, specific antibody responses and the sum κ+λ emerged as independent, signature biomarkers for CVID, with the model showcasing an area under the curve (AUC) of 0.946, Se 0.85, and Spe 0.95. This tree-decision model promises to enhance diagnostic efficiency for CVID, underscoring the sum κ+λ as a superior CVID classifier and potential diagnostic criterion within the panel.

Current Novel Targeted Therapeutic Strategies in Multiple Myeloma

Multiple myeloma (MM) is a hematologic malignancy caused by the clonal expansion of immunoglobulin-producing plasma cells in the bone marrow and/or extramedullary sites. Common manifestations of MM include anemia, renal dysfunction, infection, bone pain, hypercalcemia, and fatigue. Despite numerous recent advancements in the MM treatment paradigm, current therapies demonstrate limited long-term effectiveness and eventual disease relapse remains exceedingly common. Myeloma cells often develop drug resistance through clonal evolution and alterations of cellular signaling pathways. Therefore, continued research of new targets in MM is crucial to circumvent cumulative drug resistance, overcome treatment-limiting toxicities, and improve outcomes in this incurable disease. This article provides a comprehensive overview of the landscape of novel treatments and emerging therapies for MM grouped by molecular target. Molecular targets outlined include BCMA, GPRC5D, FcRH5, CD38, SLAMF7, BCL-2, kinesin spindle protein, protein disulfide isomerase 1, peptidylprolyl isomerase A, Sec61 translocon, and cyclin-dependent kinase 6. Immunomodulatory drugs, NK cell therapy, and proteolysis-targeting chimera are described as well.

Extended characterization of anti-CD19 CAR T cell products manufactured at the point of care using the CliniMACS Prodigy system: comparison of donor sources and process duration

BACKGROUND AIMS

The CliniMACS Prodigy closed system is widely used for the manufacturing of chimeric antigen receptor T cells (CAR-T cells). Our study presents an extensive immunophenotypic and functional characterization and comparison of the properties of anti-CD19 CAR-T cell products obtained during long (11 days) and short (7 days) manufacturing cycles using the CliniMACS Prodigy system, as well as cell products manufactured from different donor sources of T lymphocytes: from patients, from patients who underwent HSCT, and from haploidentical donors. We also present the possibility of assessing the efficiency of transduction by an indirect method.

METHODS

Seventy-six CD19 CAR-T cell products were manufactured using the CliniMACS Prodigy automated system. Immunophenotypic properties, markers of cell activation and exhaustion, antitumor, anti-CD19 specific activity in vitro of the manufactured cell products were evaluated. As an indirect method for assessing the efficiency of transduction, we used the method of functional assessment of cytokine secretion and expression of the CD107a marker after incubation of CAR-T cells with tumor targets.

RESULTS

The CliniMACS Prodigy platform can produce a product of CD19 CAR-T cells with sufficient cell expansion (4.6 × 109 cells-median for long process [LP] and 1.6 × 109-for short process [SP]), transduction efficiency (43.5%-median for LP and 41.0%-for SP), represented mainly by T central memory cell population, with low expression of exhaustion markers, and with high specific antitumor activity in vitro. We did not find significant differences in the properties of the products obtained during the 7- and 11-day manufacturing cycles, which is in favor of reducing the duration of production to 7 days, which may accelerate CAR-T therapy. We have shown that donor sources for CAR-T manufacturing do not significantly affect the composition and functional properties of the cell product.

CONCLUSIONS

This study demonstrates the possibility of using the CliniMACS Prodigy system with a shortened 7-day production cycle to produce sufficient amount of functional CAR-T cells. CAR transduction efficiency can be measured indirectly via functional assays.

Anti-Idiotypic VHHs and VHH-CAR-T Cells to Tackle Multiple Myeloma: Different Applications Call for Different Antigen-Binding Moieties

CAR-T cell therapy is at the forefront of next-generation multiple myeloma (MM) management, with two B-cell maturation antigen (BCMA)-targeted products recently approved. However, these products are incapable of breaking the infamous pattern of patient relapse. Two contributing factors are the use of BCMA as a target molecule and the artificial scFv format that is responsible for antigen recognition. Tackling both points of improvement in the present study, we used previously characterized VHHs that specifically target the idiotype of murine 5T33 MM cells. This idiotype represents one of the most promising yet challenging MM target antigens, as it is highly cancer- but also patient-specific. These VHHs were incorporated into VHH-based CAR modules, the format of which has advantages compared to scFv-based CARs. This allowed a side-by-side comparison of the influence of the targeting domain on T cell activation. Surprisingly, VHHs previously selected as lead compounds for targeted MM radiotherapy are not the best (CAR-) T cell activators. Moreover, the majority of the evaluated VHHs are incapable of inducing any T cell activation. As such, we highlight the importance of specific VHH selection, depending on its intended use, and thereby raise an important shortcoming of current common CAR development approaches.

From spear to trident: Upgrading arsenal of CAR-T cells in the treatment of multiple myeloma

Multiple myeloma (MM), marked by abnormal proliferation of plasma cells and production of monoclonal immunoglobulin heavy or light chains in the majority of patients, has traditionally been associated with poor survival, despite improvements achieved in median survival in all age groups since the introduction of novel agents. Survival has significantly improved with the development of new drugs and new treatment options, such as chimeric antigen receptor T-cell therapy (CAR-T), which have shown promise and given new hope in MM therapy. CARs are now classified as first-, second-, and third-generation CARs based on the number of monovalent to trivalent co-stimulatory molecules incorporated into their design. The scope of this review was relatively narrow because it was mainly about a comparison of the literature on the clinical application of CAR-T therapy in MM. Thus, our goal is to provide an overview of the new advances of CAR-T cells in the cure of MM, so in this review we looked at the progress of the clinical use of CAR-T cells in MM to try to provide a reference for their clinical use when managing MM.

CAR T therapies in multiple myeloma: unleashing the future

In recent years, the field of cancer treatment has witnessed remarkable breakthroughs that have revolutionized the landscape of care for cancer patients. While traditional pillars such as surgery, chemotherapy, and radiation therapy have long been available, a cutting-edge therapeutic approach called CAR T-cell therapy has emerged as a game-changer in treating multiple myeloma (MM). This novel treatment method complements options like autologous stem cell transplants and immunomodulatory medications, such as proteasome inhibitors, by utilizing protein complexes or anti-CD38 antibodies with potent complement-dependent cytotoxic effects. Despite the challenges and obstacles associated with these treatments, the recent approval of the second FDA multiple myeloma CAR T-cell therapy has sparked immense promise in the field. Thus far, the results indicate its potential as a highly effective therapeutic solution. Moreover, ongoing preclinical and clinical trials are exploring the capabilities of CAR T-cells in targeting specific antigens on myeloma cells, offering hope for patients with relapsed/refractory MM (RRMM). These advancements have shown the potential for CAR T cell-based medicines or combination therapies to elicit greater treatment responses and minimize side effects. In this context, it is crucial to delve into the history and functions of CAR T-cells while acknowledging their limitations. We can strategize and develop innovative approaches to overcome these barriers by understanding their challenges. This article aims to provide insights into the application of CAR T-cells in treating MM, shedding light on their potential, limitations, and strategies employed to enhance their efficacy.

Effects of methane emissions on multiple myeloma-related mortality rates: A World Health Organization perspective

In this research, it was aimed to evaluate effects of methane emissions on multiple myeloma related mortality rates. Two countries in Europe (Germany and Netherlands) and 1 country for each region (Turkey, USA, Brazil, Egypt, and Australia) were selected within The World Health Organization Database. Multiple myeloma mortality rates of countries between 2009 and 2019 were used as dependent variable of the research. Methane emission level and agriculture methane levels of countries were used as independent variables from The World Bank Database. Current health expenditure and healthy life expectancy were used as controlling variables. Multiple myeloma-related mortality rate was the highest in the USA, followed by Germany, Brazil, Turkey, Australia, Netherlands, and Egypt. Difference analysis results were significant (P < .05). Methane and agriculture methane emissions were the highest in the USA. Multiple myeloma mortality was positively correlated with methane emissions (R = 0.504; P < .01), agricultural methane emissions (R = 0.705; P < .01), and current health expenditure (R = 0.528; P < .01). According to year and country controlled correlation analysis results, multiple myeloma mortality (MMM) was positively correlated with methane emissions (R = 0.889; P < .01), agricultural methane emissions (R = 0.495; P < .01), and current health expenditure (R = 0.704; P < .01). Methane emission (B = 0.01; P < .05), Germany (B = 9010.81; P < .01), the USA (B = 26516.77; P < .01), and Brazil (B = 4886.14; P < .01) had significant effect on MMM. Nonagricultural methane production has an increasing effect on MMM. Therefore, by looking at the differences between agricultural methane emissions and general methane emissions, studies can be conducted that allow for more effective global comparisons.

Bispecific Antibodies in the Treatment of Multiple Myeloma

The treatment of multiple myeloma (MM) is evolving rapidly. In recent years, T-cell-based novel immunotherapies emerged as new treatment strategies for patients with relapsed/refractory MM, including highly effective new options like chimeric antigen receptor (CAR)-modified T cells and bispecific antibodies (bsAbs). Currently, B-cell maturation antigen is the most commonly used target antigen for CAR T-cell and bsAb therapies in MM. Results from different clinical trials have demonstrated promising efficacy and acceptable safety profile of bsAb in RRMM.

Incidence, timing, and management of infections in patients receiving teclistamab for the treatment of relapsed/refractory multiple myeloma in the MajesTEC-1 study

BACKGROUND

Patients with relapsed/refractory multiple myeloma are at increased risk of infection. Infections during treatment with teclistamab, the first B-cell maturation antigen-directed bispecific antibody approved for triple-class-exposed relapsed/refractory multiple myeloma, was examined in the phase 1/2 MajesTEC-1 study.

METHODS

Patients (N = 165) received subcutaneous teclistamab 1.5 mg/kg weekly after a step-up dosing schedule (0.06 mg/kg and 0.3 mg/kg, each separated by 2-4 days). Patients were monitored frequently for infections; prophylaxis and management were per institutional guidelines.

RESULTS

At a median follow-up of 22.8 months (range, 0.3-33.6), infections were reported in 132 patients (80.0%). Grade 3/4 infections occurred in 91 patients (55.2%), including COVID-19 (21.2%), respiratory infections (19.4%), Pneumocystis jirovecii pneumonia (4.2%), viral infections (4.2%), and gastrointestinal infections (1.2%). Twenty-one patients died from infections (18 from COVID-19). Median time to first onset of any-grade and grade 3 to 5 infections was 1.7 and 4.2 months, respectively. Overall, 70.9% of patients had ≥1 postbaseline immunoglobulin G (IgG) level <400 mg/dL; median time to IgG <400 mg/dL was 1.2 months (range, 0.2-19.8) and 46.1% received ≥1 dose of IgG replacement. Grade 3/4 neutropenia occurred in 65.5% of patients (median time to grade ≥3 neutropenia/febrile neutropenia was 2.3 months [range, 0-18.1]).

CONCLUSION

Based on the infection profile of B-cell maturation antigen-targeted bispecific antibodies such as teclistamab, it is recommended that clinicians and patients remain vigilant for a range of infection types throughout treatment to facilitate prompt intervention. Appropriate screening, prophylaxis, and management of infections, hypogammaglobulinemia, and neutropenia are important.

CLINICAL TRIAL REGISTRATION

NCT03145181/NCT04557098 (ClinicalTrials.gov) PLAIN LANGUAGE SUMMARY: Before starting teclistamab, patients should be up to date with vaccinations (including COVID-19) and screened for hepatitis B and C and HIV. Teclistamab should not be given to patients with any active infections. Prophylactic antimicrobials should be administered per institutional guidelines. Prophylaxis for Pneumocystis jirovecii pneumonia and herpes simplex/varicella zoster virus is recommended during teclistamab treatment. Close monitoring of infections and immunoglobulin G (IgG) levels should continue throughout teclistamab treatment. IgG replacement (administered every 3-6 weeks) should be used to maintain IgG ≥400 mg/dL. Growth factors should be considered for grade ≥3 neutropenia with infection/fever and grade 4 neutropenia.

Novel Anti-B-cell Maturation Antigen Alpha-Amanitin Antibody-drug Conjugate HDP-101 Shows Superior Activity to Belantamab Mafodotin and Enhanced Efficacy in Deletion 17p Myeloma Models

B-cell maturation antigen (BCMA) plays a pathobiologic role in myeloma and is a validated target with five BCMA-specific therapeutics having been approved for relapsed/refractory disease. However, these drugs are not curative, and responses are inferior in patients with molecularly-defined high-risk disease, including those with deletion 17p (del17p) involving the tumor suppressor TP53, supporting the need for further drug development. Del17p has been associated with reduced copy number and gene expression of RNA polymerase II subunit alpha (POLR2A) in other tumor types. We therefore studied the possibility that HDP-101, an anti-BCMA antibody drug conjugate (ADC) with the POLR2A poison α-amanitin could be an attractive agent in myeloma, especially with del17p. HDP-101 reduced viability in myeloma cell lines representing different molecular disease subtypes, and overcame adhesion-mediated and both conventional and novel drug resistance. After confirming that del17p is associated with reduced POLR2A levels in publicly available myeloma patient databases, we engineered TP53 wild-type cells with a TP53 knockout (KO), POLR2A knockdown (KD), or both, the latter to mimic del17p. HDP-101 showed potent anti-myeloma activity against all tested cell lines, and exerted enhanced efficacy against POLR2A KD and dual TP53 KO/POLR2A KD cells. Mechanistic studies showed HDP-101 up-regulated the unfolded protein response, activated apoptosis, and induced immunogenic cell death. Notably, HDP-101 impacted CD138-positive but not-negative primary cells, showed potent efficacy against aldehyde dehydrogenase-positive clonogenic cells, and eradicated myeloma in an in vivo cell line-derived xenograft (CDX). Interestingly, in the CDX model, prior treatment with HDP-101 precluded subsequent engraftment on tumor cell line rechallenge in a manner that appeared to be dependent in part on natural killer cells and macrophages. Finally, HDP-101 was superior to the BCMA-targeted ADC belantamab mafodotin against cell lines and primary myeloma cells in vitro, and in an in vivo CDX. Together, the data support the rationale for translation of HDP-101 to the clinic, where it is now undergoing Phase I trials, and suggest that it could emerge as a more potent ADC for myeloma with especially interesting activity against the high-risk del17p myeloma subtype.

BCMA-targeted bortezomib nanotherapy improves therapeutic efficacy, overcomes resistance, and modulates the immune microenvironment in multiple myeloma

Bortezomib (BTZ) is a standard-of-care treatment in multiple myeloma (MM); however, adverse side effects and development of resistance limit its long term benefit. To improve target specificity, therapeutic efficacy, and overcome resistance, we designed nanoparticles that encapsulate BTZ and are surface-functionalized with BCMA antibodies (BCMA-BTZ-NPs). We confirmed efficient cellular internalization of the BCMA-BTZ-NPs only in BCMA-expressing MM cells, but not in BCMA-knockout (KO) cells. In addition, BCMA-BTZ-NPs showed target-specific cytotoxicity against MM cell lines and primary tumor cells from MM patients. The BCMA-BTZ-NPs entered the cell through receptor-mediated uptake, which escapes a mechanism of BTZ resistance based on upregulating P-glycoprotein. Furthermore, BCMA-BTZ-NPs induced cell death more efficiently than non-targeted nanoparticles or free BTZ, triggering potent mitochondrial depolarization followed by apoptosis. In BTZ-resistant cells, BCMA-BTZ-NPs inhibited proteasome activity more effectively than free BTZ or non-targeted nanoparticles. Additionally, BCMA-BTZ-NPs enhanced immunogenic cell death and activated the autophagic pathway more than free BTZ. Finally, we found that BCMA-BTZ-NPs selectively accumulated at the tumor site in a murine xenograft model, enhanced tumor reduction, and prolonged host survival. These results suggest BCMA-BTZ-NPs provide a promising therapeutic strategy for enhancing the efficacy of BTZ and establish a framework for their evaluation in a clinical setting.

Emerging Therapeutic Targets and Drug Resistance Mechanisms in Immunotherapy of Hematological Malignancies

CAR-T cell therapy has revolutionized the treatment of hematological malignancies with high remission rates in the case of ALL and NHL. This therapy has some limitations such as long manufacturing periods, persistent restricted cell sources and high costs. Moreover, combination regimens increase the risk of immune-related adverse events, so the identification new therapeutic targets is important to minimize the risk of toxicities and to guide more effective approaches. Cancer cells employ several mechanisms to evade immunosurveillance, which causes resistance to immunotherapy; therefore, a very important therapeutic approach is to focus on the development of rational combinations of targeted therapies with non-overlapping toxicities. Recent progress in the development of new inhibitory clusters of differentiation (CDs), signaling pathway molecules, checkpoint inhibitors, and immunosuppressive cell subsets and factors in the tumor microenvironment (TME) has significantly improved anticancer responses. Novel strategies regarding combination immunotherapies with CAR-T cells are the most promising approach to cure cancer.

Novel Immunotherapies and Combinations: The Future Landscape of Multiple Myeloma Treatment

In multiple myeloma impressive outcomes have improved with the introduction of new therapeutic approaches, mainly those including naked monoclonal antibodies such as daratumumab and isatuximab. However, moving to earlier lines of therapy with effective anti-myeloma drugs led to an increase in the number of patients who developed multi-refractoriness to them early on. Currently, triple- or multi-refractory MM represents an unmet medical need, and their management remains a complicated challenge. The recent approval of new immunotherapeutic approaches such as conjugated monoclonal antibodies, bispecific antibodies, and CAR T cells could be a turning point for these heavily pretreated patients. Nevertheless, several issues regarding their use are unsolved, such as how to select patients for each strategy or how to sequence these therapies within the MM therapeutic landscape. Here we provide an overview of the most recent data about approved conjugated monoclonal antibody belantamab, mafodotin, bispecific antibody teclistamab, and other promising compounds under development, mainly focusing on the ongoing clinical trials with monoclonal antibody combination approaches in advanced and earlier phases of MM treatment.

CAR-T-Cell Therapy in Multiple Myeloma: B-Cell Maturation Antigen (BCMA) and Beyond

Significant progress has been achieved in the realm of therapeutic interventions for multiple myeloma (MM), leading to transformative shifts in its clinical management. While conventional modalities such as surgery, radiotherapy, and chemotherapy have improved the clinical outcomes, the overarching challenge of effecting a comprehensive cure for patients afflicted with relapsed and refractory MM (RRMM) endures. Notably, adoptive cellular therapy, especially chimeric antigen receptor T-cell (CAR-T) therapy, has exhibited efficacy in patients with refractory or resistant B-cell malignancies and is now also being tested in patients with MM. Within this context, the B-cell maturation antigen (BCMA) has emerged as a promising candidate for CAR-T-cell antigen targeting in MM. Alternative targets include SLAMF7, CD38, CD19, the signaling lymphocyte activation molecule CS1, NKG2D, and CD138. Numerous clinical studies have demonstrated the clinical efficacy of these CAR-T-cell therapies, although longitudinal follow-up reveals some degree of antigenic escape. The widespread implementation of CAR-T-cell therapy is encumbered by several barriers, including antigenic evasion, uneven intratumoral infiltration in solid cancers, cytokine release syndrome, neurotoxicity, logistical implementation, and financial burden. This article provides an overview of CAR-T-cell therapy in MM and the utilization of BCMA as the target antigen, as well as an overview of other potential target moieties.

Recruiting In Vitro Transcribed mRNA against Cancer Immunotherapy: A Contemporary Appraisal of the Current Landscape

Over 100 innovative in vitro transcribed (IVT)-mRNAs are presently undergoing clinical trials, with a projected substantial impact on the pharmaceutical market in the near future. Τhe idea behind this is that after the successful cellular internalization of IVT-mRNAs, they are subsequently translated into proteins with therapeutic or prophylactic relevance. Simultaneously, cancer immunotherapy employs diverse strategies to mobilize the immune system in the battle against cancer. Therefore, in this review, the fundamental principles of IVT-mRNA to its recruitment in cancer immunotherapy, are discussed and analyzed. More specifically, this review paper focuses on the development of mRNA vaccines, the exploitation of neoantigens, as well as Chimeric Antigen Receptor (CAR) T-Cells, showcasing their clinical applications and the ongoing trials for the development of next-generation immunotherapeutics. Furthermore, this study investigates the synergistic potential of combining the CAR immunotherapy and the IVT-mRNAs by introducing our research group novel, patented delivery method that utilizes the Protein Transduction Domain (PTD) technology to transduce the IVT-mRNAs encoding the CAR of interest into the Natural Killer (NK)-92 cells, highlighting the potential for enhancing the CAR NK cell potency, efficiency, and bioenergetics. While IVT-mRNA technology brings exciting progress to cancer immunotherapy, several challenges and limitations must be acknowledged, such as safety, toxicity, and delivery issues. This comprehensive exploration of IVT-mRNA technology, in line with its applications in cancer therapeutics, offers valuable insights into the opportunities and challenges in the evolving landscape of cancer immunotherapy, setting the stage for future advancements in the field.

Adverse events of antibody-drug conjugates on the ocular surface in cancer therapy

Antibody-drug conjugates consist of a monoclonal antibody attached to a cytotoxic therapeutic molecule by a connector. This association allows a highly specific therapy, which increases their effectiveness and decreases their potential toxicity. This new therapy emerged approximately 20 years ago; since then, numerous combinations have appeared in the field of treatment-related neoplasms as an alternative for patients who do not achieve good results with conventional treatment options. Adverse effects of these drugs on the ocular surface are frequent and varied. Their prevalence ranges from 20 to 90% depending on the drug and administration condition, probably due to multiple receptor-mediated factors or mechanisms not mediated by specific receptors, such as macropinocytosis. These adverse events can greatly limit patients' comfort; thus, the objectives of this article were, in the first place, to compile the information currently available on different types of adverse effects of antibody-drug conjugates on the ocular surface, including pathophysiology, prevalence, and treatment, and in second place, to contribute to the correct identification and management of these events, which will result in a lower rate of cessation of treatment, which is necessary for the survival of candidate patients.

Cilta-cel, a BCMA-targeting CAR-T therapy for heavily pretreated patients with relapsed/refractory multiple myeloma

Cilta-cel, a BCMA-targeting chimeric antigen receptor T-cell therapy for multiple myeloma, was approved in USA on 28 February 2022, for patients with relapsed or refractory disease who have received ≥4 prior lines of therapy, including a proteasome inhibitor, an immunomodulatory drug, and an anti-CD38 monoclonal antibody. Approval in the EU followed for patients with ≥3 prior therapies. At median 28-month follow-up, the pivotal CARTITUDE-1 trial showed a 98% response rate (83% stringent complete response); median progression-free survival had not been reached, and adverse events could be managed with supportive therapy. Cilta-cel efficacy and safety in earlier lines of therapy, and its optimal sequencing in a complex treatment landscape are important areas of investigation.

Anti‑BCMA CAR‑T cell immunotherapy for relapsed or refractory multiple myeloma

The present study aimed to study the efficacy and adverse effects of anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T (CAR-T) cell therapy in relapsed or refractory multiple myeloma. Patients were divided into three dose groups based on cell therapy concentration. After CAR-T cell therapy for 10 patients with recurrent or refractory multiple myeloma, the patients were monitored and evaluated regularly to observe the efficacy and adverse reactions of CAR-T cell therapy. At a median follow-up of 337 (253-504) days, one patient succumbed 24 days due to rapidly progressing disease. The overall response rate of nine patients was 88.9%, including 77.8% (7/9) with minimal residual disease negative complete remission (CR) and 11.1% (1/9) with partial remission. A total of three patients were maintained in remission state for more than a year and eight were maintained for more than six months. Among the three patients with extramedullary invasion, two extramedullary lesions disappeared and one was stable. The highest copy number of CAR-T cells in seven patients with CR was >1x105 copies/µl gDNA, and the best therapeutic effect can be achieved within 30 (7-30) days after the copy number of CAR-T cells reached 1x105 copies/µl genomic DNA. The median onset time in the nine patients was 43 (22-169) days, and the median progression-free survival was 337 (253-504). Among the 10 patients, nine (90%) had cytokine release syndrome, all of which were below grade II. There were nine (90%) patients with hematological adverse reactions, six (60%) patients with severe anemia, five (50%) patients with grade III and above leukopenia, five (50%) patients with granulocytopenia, four (40%) patients with grade III and above thrombocytopenia, and three (30%) patients with grade III and above pancytopenia. It was concluded that anti-BCMA CAR-T cell therapy is a promising treatment method for relapsed or refractory multiple myeloma and extramedullary invasion, with stable efficacy and controllable adverse effects.

Idecabtagene vicleucel for relapsed and refractory multiple myeloma: post hoc 18-month follow-up of a phase 1 trial

Idecabtagene vicleucel (ide-cel) is a B-cell-maturation antigen (BCMA)-directed chimeric antigen receptor T cell therapy. We performed a post hoc analysis of a single-arm phase 1 multicenter study in relapsed/refractory multiple myeloma (CRB-401) (n = 62; median follow-up, 18.1 months). The primary endpoint was safety outcomes, and secondary endpoints included overall response rate (ORR), complete response (CR) and very good partial response (VGPR). The study met its primary endpoint with low rates of grade 3/grade 4 cytokine release syndrome (6.5%) and neurotoxicity (1.6%). ORR was 75.8%; 64.5% achieved VGPR or better and 38.7% achieved CR or stringent CR. Among exploratory endpoints, median duration of response, progression-free survival (PFS) and overall survival were 10.3, 8.8 and 34.2 months, respectively, and ide-cel expansion in blood and bone marrow correlated with clinical efficacy and postinfusion reduction of soluble BCMA. Patients with PFS ≥ 18 months had more naive and less exhausted T cells in apheresis material and improved functional T cell phenotype in the drug product compared with those with less durable responses. These results confirm ide-cel safety, tolerability and efficacy and describe T cell qualities that correlate with durable response. Clinicaltrials.gov identifier : NCT02658929 .

Cerebrospinal fluid soluble CD27 is associated with CD8+ T cells, B cells and biomarkers of B cell activity in relapsing-remitting multiple sclerosis

Cerebrospinal fluid (CSF) soluble CD27 (sCD27) is a sensitive biomarker of intrathecal inflammation. Although generally considered a biomarker of T cell activation, CSF sCD27 has been shown to correlate with biomarkers of B cell activity in multiple sclerosis. We analyzed CSF from 40 patients with relapsing-remitting multiple sclerosis (RRMS) and nine symptomatic controls using flow cytometry and multiplex electrochemiluminescence immunoassays. CSF sCD27 levels were increased in RRMS and correlated with IgG index, soluble B cell maturation antigen, cell count, B cell frequency and CD8+ T cell frequency. We provide new data indicating that CSF sCD27 is associated with CD8+ T cells and B cells in RRMS.

Real-World Effectiveness and Safety of Belantamab Mafodotin Monotherapy in Triple-Class Refractory Multiple Myeloma

B-cell maturation antigen (BCMA) is a promising therapeutic target for multiple myeloma (MM). The aim of this study was to assess the effectiveness and tolerability of monotherapy with the conjugated anti-BCMA monoclonal antibody belantamab mafodotin in triple-class refractory patients with MM in real-world practice. Patients refractory to at least one proteasome inhibitor, one immunomodulatory drug, and one anti-CD38 monoclonal antibody received belantamab mafodotin at 2.5 mg/kg intravenously every 3 weeks. Overall, 27 patients with a median age of 65 years (range 41-81) were included. Of these, 52% were male and the median number of prior lines of treatment was 5 (4-10). The overall response rate (partial response or better) was 52%, whereas the disease control rate (stable disease or better) was 70%. The median progression-free survival (PFS) was 2 months (95%CI: 0-7), whereas the median PFS among the responders was 12 months (95%CI: 6-18). Regarding the toxicity profile, the most common toxicity was eye toxicity, in 44% of the patients. Keratopathy grade 2-3 was reported in 33.3% of the patients. In conclusion, belantamab mafodotin showed a safety and efficacy profile consistent with the results of the registrational study. Importantly, heavily pretreated patients who responded to treatment derived a substantial survival benefit.

The Role of Bispecific Antibodies in Relapsed Refractory Multiple Myeloma: A Systematic Review

Multiple myeloma is a heterogeneous clonal malignant plasma cell disorder, which remains incurable despite the therapeutic armamentarium's evolution. Bispecific antibodies (BsAbs) can bind simultaneously to the CD3 T-cell receptor and tumor antigen of myeloma cells, causing cell lysis. This systematic review of phase I/II/III clinical trials aimed to analyze the efficacy and safety of BsAbs in relapsed refractory multiple myeloma (RRMM). A thorough literature search was performed using PubMed, Cochrane Library, EMBASE, and major conference abstracts. A total of 18 phase I/II/III studies, including 1283 patients, met the inclusion criteria. Among the B-cell maturation antigen (BCMA)-targeting agents across 13 studies, the overall response rate (ORR) ranged between 25% and 100%, with complete response/stringent complete response (CR/sCR) between 7 and 38%, very good partial response (VGPR) between 5 and 92%, and partial response (PR) between 5 and 14%. Among the non-BCMA-targeting agents across five studies, the ORR ranged between 60 and 100%, with CR/sCR seen in 19-63%, and VGPR in 21-65%. The common adverse events were cytokine release syndrome (17-82%), anemia (5-52%), neutropenia (12-75%), and thrombocytopenia (14-42%). BsAbs have shown promising efficacy against RRMM cohorts with a good safety profile. Upcoming phase II/III trials are much awaited, along with the study of other agents in concert with BsAbs to gauge response.

Outcomes of Penta-Refractory Multiple Myeloma Patients Treated with or without BCMA-Directed Therapy

Despite advances in treatment, outcomes remain poor for patients with penta-relapsed refractory multiple myeloma (RRMM). In this retrospective analysis, we evaluated the survival outcomes of penta-RRMM patients treated with (BCMA)- directed therapy (BDT). We identified 78 patients with penta-RRMM. Median age was 65 years, 29 (37%) had R-ISS stage III disease, 63 (81%) had high-risk cytogenetics, and 45 (58%) had extra-medullary disease. Median LOT prior to penta-refractory state was 5 (3-12). Amongst penta-RRMM, 43 (55%) were treated with BDT, 35 (45%) were not treated with BDT. Type of BDT received included belantamab mafadotin 15 (35%), Chimeric Antigen Receptor T-cell therapy 9 (21%), BCMA monoclonal antibody 6 (14%), and Bispecific T-cell engager 2 (5%). Eleven (25%) patients received more than one BDT. No significant differences were identified between baseline characteristics for the two groups. Patients treated with a BDT had better median overall survival, 17 vs. 6 months, HR 0.3 p-value < 0.001. Poor performance status, white race, and high-risk cytogenetics were associated with worse outcomes, whereas using a BDT was associated with better outcomes. Patients with penta-refractory MM have poor outcomes. Our retrospective analysis showed a significant survival benefit using BDT when compared to non-BDT for patients with penta-RRMM.

Treatment Strategy for Ultra-High-Risk Multiple Myelomas with Chromosomal Aberrations Considering Minimal Residual Disease Status and Bone Marrow Microenvironment

Despite the development of anti-myeloma therapeutics, such as proteasome inhibitors, immunomodulatory drugs, anti-CD38 monoclonal antibodies, and autologous stem cell transplantation (ASCT), multiple myeloma remains incurable. A trial treatment combining four drugs-daratumumab, carfilzomib, lenalidomide, and dexamethasone-followed by ASCT frequently results in minimal residual disease (MRD) negativity and prevents progressive disease in patients with standard- and high-risk cytogenetics; however, it is insufficient to overcome the poor outcomes in patients with ultra-high-risk chromosomal aberration (UHRCA). In fact, MRD status in autografts can predict clinical outcomes after ASCT. Therefore, the current treatment strategy might be insufficient to overcome the negative impact of UHRCA in patients with MRD positivity after the four-drug induction therapy. High-risk myeloma cells lead to poor clinical outcomes not only by aggressive myeloma behavior but also via the generation of a poor bone marrow microenvironment. Meanwhile, the immune microenvironment effectively suppresses myeloma cells with a low frequency of high-risk cytogenetic abnormalities in early-stage myeloma compared to late-stage myeloma. Therefore, early intervention might be key to improving clinical outcomes in myeloma patients. The purpose of this review is to improve clinical outcomes in patients with UHRCA by considering MRD assessment results and improvement of the microenvironment.

Preclinical discovery and initial clinical data of WVT078, a BCMA × CD3 bispecific antibody

B-cell maturation antigen (BCMA) is an ideal target in multiple myeloma (MM) due to highly specific expression in malignant plasma cells. BCMA-directed therapies including antibody drug conjugates, chimeric antigen receptor-T cells and bispecific antibodies (BsAbs) have shown high response rates in MM. WVT078 is an anti-BCMA× anti-CD3 BsAb that binds to BCMA with subnanomolar-affinity. It was selected based on potent T cell activation and anti-MM activity in preclinical models with favorable tolerability in cynomolgus monkey. In the ongoing first-in-human phase I dose-escalation study (NCT04123418), 33 patients received intravenous WVT078 once weekly at escalated dosing. At the active doses of 48-250 µg/kg tested to date (n = 26), the overall response rate (ORR) was 38.5% (90% CI: 22.6-56.4%) and the complete response rate (CRR, stringent complete response + complete response) was 11.5%, (90% CI: 3.2-27.2%). At the highest dose level tested, the ORR was 75% (3 of 4 patients). 26 (78.8%) patients reported at least one Grade ≥3 AE and 16 of these AEs were suspected to be drug related. 20 patients (60.6%) experienced cytokine release syndrome. WVT078 has an acceptable safety profile and shows preliminary evidence of clinical activity at doses tested to date.

Assessing the treatment pattern, health care resource utilisation, and economic burden of multiple myeloma in France using the Système National des Données de Santé (SNDS) database: a retrospective cohort study

BACKGROUND

Real-world data on health care resource utilisation (HCRU) and costs for French patients with multiple myeloma (MM) are limited due to the quickly evolving MM treatment landscape. This retrospective, national-level study quantified the MM economic burden in France.

METHODS

The study included patients with newly diagnosed MM from the Système National des Données de Santé coverage claims database between 2013 and 2018 who received active treatment within 30 days of diagnosis. HCRU included hospitalisations, drugs, consultations, procedures, tests, devices, transport, and sick leave. Costs were annualized to 2019 prices. Drug treatments, reported by line of therapy (LOT), were algorithmically defined using drug regimen, duration of therapy, and gaps between treatments. Analyses were stratified by stem cell transplantation status and LOT.

RESULTS

Among 6413 eligible patients, 6229 (97.1%) received ≥ 1 identifiable LOT; most received 1 (39.8%) or 2 LOT (27.5%) during follow-up. Average annual hospitalisation was 6.3 episodes/patient/year (median duration: 11.6 days). The average annual cost/patient was €58.3 K. Key cost drivers were treatment (€28.2 K; 39.5% of total HCRU within one year of MM diagnosis) and hospitalisations (€22.2 K; 48.6% of total HCRU costs in first year). Monthly treatment-related costs increased from LOT1 (€2.447 K) and LOT5 + (€7.026 K); only 9% of patients received LOT5 + . At LOT4 + , 37 distinct regimens were identified. Hospitalisation costs were higher in patients with stem cell transplantation than total population, particularly in the first year.

CONCLUSIONS

This study showed a high economic burden of MM in France (€72.37 K/patient/year in the first year) and the diversity of regimens used in late-line treatments.

Target Antigen Attributes and Their Contributions to Clinically Approved Antibody-Drug Conjugates (ADCs) in Haematopoietic and Solid Cancers

Antibody drug conjugates (ADCs) are powerful anti-cancer therapies comprising an antibody joined to a cytotoxic payload through a chemical linker. ADCs exploit the specificity of antibodies for their target antigens, combined with the potency of cytotoxic drugs, to selectively kill target antigen-expressing tumour cells. The recent rapid advancement of the ADC field has so far yielded twelve and eight ADCs approved by the US and EU regulatory bodies, respectively. These serve as effective targeted treatments for several haematological and solid tumour types. In the development of an ADC, the judicious choice of an antibody target antigen with high expression on malignant cells but restricted expression on normal tissues and immune cells is considered crucial to achieve selectivity and potency while minimising on-target off-tumour toxicities. Aside from this paradigm, the selection of an antigen for an ADC requires consideration of several factors relating to the expression pattern and biological features of the target antigen. In this review, we discuss the attributes of antigens selected as targets for antibodies used in clinically approved ADCs for the treatment of haematological and solid malignancies. We discuss target expression, functions, and cellular kinetics, and we consider how these factors might contribute to ADC efficacy.

The Effect of Belantamab Mafodotin on Primary Myeloma–Stroma Co-Cultures: Asymmetrical Mitochondrial Transfer between Myeloma Cells and Autologous Bone Marrow Stromal Cells

Belantamab mafodotin (belamaf) is an afucosylated monoclonal antibody conjugated to the microtubule disrupter monomethyl auristatin-F (MMAF) that targets B cell maturation antigen (BCMA) on the surface of malignant plasma cells. Belamaf can eliminate myeloma cells (MMs) through several mechanisms. On the one hand, in addition to inhibiting BCMA-receptor signaling and cell survival, intracellularly released MMAF disrupts tubulin polymerization and causes cell cycle arrest. On the other hand, belamaf induces effector cell-mediated tumor cell lysis via antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis. In our in vitro co-culture model, the consequences of the first mentioned mechanism can be investigated: belamaf binds to BCMA, reduces the proliferation and survival of MMs, and then enters the lysosomes of malignant cells, where MMAF is released. The MMAF payload causes a cell cycle arrest at the DNA damage checkpoint between the G2 and M phases, resulting in caspase-3-dependent apoptosis. Here, we show that primary MMs isolated from different patients can vary widely in terms of BCMA expression level, and inadequate expression is associated with extremely high resistance to belamaf according to our cytotoxicity assay. We also reveal that primary MMs respond to increasing concentrations of belamaf by enhancing the incorporation of mitochondria from autologous bone marrow stromal cells (BM-MSCs), and as a consequence, MMs become more resistant to belamaf in this way, which is similar to other medications we have analyzed previously in this regard, such as proteasome inhibitor carfilzomib or the BCL-2 inhibitor venetoclax. The remarkable resistance against belamaf observed in the case of certain primary myeloma cell cultures is a cause for concern and points towards the use of combination therapies to overcome the risk of antigen escape.

Identifying tumour microenvironment-related signature that correlates with prognosis and immunotherapy response in breast cancer

Tumor microenvironment (TME) plays important roles in prognosis and immune evasion. However, the relationship between TME-related genes and clinical prognosis, immune cell infiltration, and immunotherapy response in breast cancer (BRCA) remains unclear. This study described the TME pattern to construct a TME-related prognosis signature, including risk factors PXDNL, LINC02038 and protective factors SLC27A2, KLRB1, IGHV1-12 and IGKV1OR2-108, as an independent prognostic factor for BRCA. We found that the prognosis signature was negatively correlated with the survival time of BRCA patients, infiltration of immune cells and the expression of immune checkpoints, while positively correlated with tumor mutation burden and adverse treatment effects of immunotherapy. Upregulation of PXDNL and LINC02038 and downregulation of SLC27A2, KLRB1, IGHV1-12 and IGKV1OR2-108 in high-risk score group synergistically contribute to immunosuppressive microenvironment which characterized by immunosuppressive neutrophils, impaired cytotoxic T lymphocytes migration and natural killer cell cytotoxicity. In summary, we identified a TME-related prognostic signature in BRCA, which was connected with immune cell infiltration, immune checkpoints, immunotherapy response and could be developed for immunotherapy targets.

[Management of neurotoxicity following CAR-T cell therapy: Recommendations of the SFGM-TC]

The immune effector cell-associated syndrome (ICANS) has been described as the second most frequent specific complication following CAR-T cell therapy. The median time to the onset of neurological symptoms is five days after CAR-T infusion. ICANS can be concomitant to cytokine release syndrome but often follows the resolution of the latter. However, 10 % of patients experience delayed onset after 3 weeks of CAR-T cell infusion. The duration of symptoms is usually short, around five days if an early appropriate treatment is given. Symptoms are heterogeneous, ranging from mild symptoms quickly reversible (alterations of consciousness, deterioration in handwriting) to more serious forms with seizures or even a coma. The ICANS severity is currently based on the ASTCT score. The diagnosis of ICANS is clinical but EEG, MRI and lumbar punction can help ruling out alternative diagnoses. The first line treatment consists of high-dose corticosteroids. During the twelfth edition of practice harmonization workshops of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), a working group focused its work on updating the SFGM-TC recommendations on the management of ICANS. In this review we discuss the management of ICANS and other neurological toxicities in patients undergoing of CAR-T cell therapy. These recommendations apply to commercial CAR-T cells, in order to guide strategies for the management neurological complications associated with this new therapeutic approach.

The role of soluble B cell maturation antigen as a biomarker in multiple myeloma

Currently used stratification models in myeloma precursor disease as well as staging systems and response criteria in myeloma have limitations including failure to identify functionally high-risk myeloma patients. B-cell maturation antigen, a transmembrane glycoprotein required for long-lived plasma cells, is specific and expressed by myeloma cells. When it sheds from the surface of myeloma cells it can be measured in the blood as serum (sBCMA) and correlated with clinical outcomes in myeloma precursor disease as well as in active myeloma. We performed a literature review using PubMed and found 825 articles since 1992 of which any articles related to sBCMA were reviewed. These studies show the potential of sBCMA to become an important biomarker in myeloma. Here, we describe the potential advantages of sBCMA in the biology, diagnosis, prognosis, and surveillance of myeloma, while also reviewing the challenges that lie ahead before it can be implemented as a clinical tool.

Delayed boosting improves human antigen-specific Ig and B cell responses to the RH5.1/AS01B malaria vaccine

Modifications to vaccine delivery that increase serum antibody longevity are of great interest for maximizing efficacy. We have previously shown that a delayed fractional (DFx) dosing schedule (0-1-6 month) - using AS01B-adjuvanted RH5.1 malaria antigen - substantially improves serum IgG durability as compared with monthly dosing (0-1-2 month; NCT02927145). However, the underlying mechanism and whether there are wider immunological changes with DFx dosing were unclear. Here, PfRH5-specific Ig and B cell responses were analyzed in depth through standardized ELISAs, flow cytometry, systems serology, and single-cell RNA-Seq (scRNA-Seq). Data indicate that DFx dosing increases the magnitude and durability of circulating PfRH5-specific B cells and serum IgG1. At the peak antibody magnitude, DFx dosing was distinguished by a systems serology feature set comprising increased FcRn binding, IgG avidity, and proportion of G2B and G2S2F IgG Fc glycans, alongside decreased IgG3, antibody-dependent complement deposition, and proportion of G1S1F IgG Fc glycan. Concomitantly, scRNA-Seq data show a higher CDR3 percentage of mutation from germline and decreased plasma cell gene expression in circulating PfRH5-specific B cells. Our data, therefore, reveal a profound impact of DFx dosing on the humoral response and suggest plausible mechanisms that could enhance antibody longevity, including improved FcRn binding by serum Ig and a potential shift in the underlying cellular response from circulating short-lived plasma cells to nonperipheral long-lived plasma cells.

Efficacy and safety of cilta-cel in patients with progressive multiple myeloma after exposure to other BCMA-targeting agents

B-cell maturation antigen (BCMA)-targeting therapies, including bispecific antibodies (BsAbs) and antibody-drug conjugates (ADCs), are promising treatments for multiple myeloma (MM), but disease may progress after their use. CARTITUDE-2 is a phase 2, multicohort study evaluating the safety and efficacy of cilta-cel, an anti-BCMA chimeric antigen receptor T therapy, in various myeloma patient populations. Patients in cohort C progressed despite treatment with a proteasome inhibitor, immunomodulatory drug, anti-CD38 antibody, and noncellular anti-BCMA immunotherapy. A single cilta-cel infusion was given after lymphodepletion. The primary end point was minimal residual disease (MRD) negativity at 10-5. Overall, 20 patients were treated (13 ADC exposed; 7 BsAb exposed; 1 in the ADC group also had prior BsAb exposure). Sixteen (80%) were refractory to prior anti-BCMA therapy. At a median follow-up of 11.3 months (range, 0.6-16.0), 7 of 20 (35%) patients were MRD negative (7 of 10 [70.0%] in the MRD-evaluable subset). Overall response rate (95% confidence interval [CI]) was 60.0% (36.1-80.9). Median duration of response and progression-free survival (95% CI) were 11.5 (7.9-not estimable) and 9.1 (1.5-not estimable) months, respectively. The most common adverse events were hematologic. Cytokine release syndrome occurred in 12 (60%) patients (all grade 1-2); 4 had immune effector cell-associated neurotoxicity syndrome (2 had grade 3-4); none had parkinsonism. Seven (35%) patients died (3 of progressive disease, 4 of adverse events [1 treatment related, 3 unrelated]). Cilta-cel induced favorable responses in patients with relapsed/refractory MM and prior exposure to anti-BCMA treatment who had exhausted other therapies. This trial was registered at www.clinicaltrials.gov as NCT04133636.

A Novel BCMA Immunohistochemistry Assay Reveals a Heterogenous and Dynamic BCMA Expression Profile in Multiple Myeloma

B-cell maturation antigen (BCMA) is a promising target for the treatment of multiple myeloma (MM) because the expression of this protein is largely limited to B-cell sets, plasma cells, MM, and other B-cell malignancies. Early studies assessing BCMA protein expression and localization have used insufficiently qualified immunohistochemistry assays, which have reported broad ranges of BCMA expression. As a result, our understanding of BCMA tissue expression derived from these data is limited, specifically the prevalence of BCMA expression on the cell surface/membrane, which has mechanistic relevance to the antimyeloma activity of several novel biotherapeutics. Here, we report on the qualification and application of a novel anti-BCMA immunohistochemistry antibody, 805G12. This antibody shows robust detection of BCMA in formalin-fixed, decalcified bone marrow tissue and provides key insights into membrane BCMA expression. The clone 805G12, which was raised against an intracellular C-terminal domain peptide of membrane BCMA, exhibited increased sensitivity and superior specificity across healthy and diseased tissue compared with the frequently referenced commercial reagent AF193. The new clone also demonstrated a broad range of expression of BCMA in MM and diffuse large B-cell lymphoma specimens. Additionally, cross-reactivity with closely related tumor necrosis factor receptor family members was observed with AF193 but not with 805G12. Furthermore, via established 805G12 and other independent BCMA assays, it was concluded that proteolytic processing by γ-secretase contributes to the levels of BCMA localized to the plasma membrane. As BCMA-directed therapeutics emerge to address the need for more effective treatment in the relapsed or refractory MM disease setting, the implementation of a qualified assay would ensure that reliable and consistent data on BCMA surface expression are used to inform clinical trial decisions and patient responses.

Species Differences in Blood Lymphocyte Responses After Spinal Cord Injury

People with spinal cord injury (SCI) get recurrent infections, such as urinary tract infections (UTIs) and pneumonias, that cause mortality and worsen neurological recovery. Over the past decades, researchers have proposed that post-SCI lymphopenia and decreased lymphocyte function increase susceptibility to infections and worsen neurological outcome in humans, leading to a condition called SCI-induced immune depression syndrome (SCI-IDS). In this review, we explore how SCI affects blood lymphocyte homeostasis and function in humans and rodents. Understanding how SCI affects blood lymphocytes will help the management of recurrent infections in spinal cord injured people and shed light on the clinical translation of findings in animal models to humans.

Effect of Daratumumab combined with Chemotherapy on Immune Function in Patients with Relapsed/Refractory Multiple Myeloma and Observation of its Clinical Efficacy

Objective

To evaluate the clinical efficacy and immune function of Daratumumab combined with chemotherapy in patients with relapsed/refractory multiple myeloma (RRMM).

Methods

Eighty patients with RRMM treated in Xingtai People's Hospital from January, 2020 to December, 2021 were randomly divided into two groups. Patients in the study group were treated with Daratumumab combined with PAD regimen, while patients in the control group were provided with PAD regimen alone. Further comparison was performed on the therapeutic effects, adverse drug reactions, the levels of T lymphocyte subsets CD3+, CD4+, CD8+ and CD4+/CD8+, the positive expression rate of CD38 and the expression level of Notch-1 on the membrane of plasma cells between the two groups.

Results

The overall response rate in the study group (67.50%) was significantly better than that in the control group (45.00%). There was no significant difference in the incidence of adverse reactions between the two groups. After treatment, the reviewed levels of CD3+, CD4+ and CD4+/CD8+ were obviously higher in the study group than those in the control group, while the positive expression rate of CD38 and the expression level of Notch one on the membrane of plasma cells were both lower than those in the control group (p<0.05).

Conclusion

Daratumumab combined with a PAD regimen is a safe and effective approach that has a definite curative effect on patients with RRMM, which can improve immune function significantly and result in no significant increase in adverse reactions.