Clinical and Biological Correlates of Neurotoxicity Associated with CAR T-cell Therapy in Patients with B-cell Acute Lymphoblastic Leukemia

Acute Symptomatic Seizures During CAR T-Cell Therapy for Hematologic Malignancies: Tri-Site Mayo Clinic Experience

BACKGROUND AND OBJECTIVES

Chimeric antigen receptor T-cell (CAR T-cell) therapy is associated with neurotoxicity, which may include acute symptomatic seizures (ASySs). Specific risk factors and short-term and long-term outcomes of ASyS associated with CAR T-cell therapy have not been well investigated.

METHODS

This retrospective cohort study evaluated incidence and risk factors for ASyS during CAR T-cell therapy. We included patients treated at Mayo Clinic in Minnesota, Florida, and Arizona who underwent CAR T-cell therapy for hematologic malignancies from October 2019 to November 2023. Pretreatment demographics, clinical information, type of CAR T-cell therapy, neuroimaging, laboratories during treatment, and clinical features during admission were analyzed. Data on treatment and prevalence of seizures, EEG, and survival at the last follow-up were assessed. T-tests and nonparametric testing were performed on categorical and continuous data, respectively. Multivariable analysis was also performed.

RESULTS

We included 180 patients (mean age 62.3 years, 57.2% women) with 8 (4.4%) developing ASyS at a mean of 8.0 ± 5.3 days after therapy. Earlier onset of cytotoxic release syndrome (odds ratio [OR] 1.81, 95% CI 0.62-2.99, p = 0.007), higher grade immune effector cell-associated neurotoxicity syndrome (ICANS) (OR -1.43, 95% CI -1.86 to -1.00, p < 0.001), focal neurologic deficits (OR 7.15, 95% CI 1.60-32.14, p = 0.007), and cefepime (OR 0.58, 95% CI 0.51-0.65, p = 0.022) exposure were significantly associated with a higher risk of ASyS. A multivariable model accounting for age and sex fit best using the lowest minimum immune effector cell encephalopathy score and highest ICANS grade (R2 = 0.555, χ2 = 28.507, p < 0.001). ASyS was associated with death at the last follow-up (OR 0.48, 95% CI 0.41-0.56, p = 0.007), although short-term outcomes were not affected by ASyS. Nonprotocolized antiseizure medication (ASM) prophylaxis did not affect ASyS incidence.

DISCUSSION

This study suggests a low risk of ASyS because of CAR T-cell therapy, with certain risk factors that may be predictive of ASyS and lack of a definitive and direct association of ASyS with outcomes. The current approach to ASM prophylaxis should be reconsidered when ICANS is encountered. This study is limited by its retrospective nature and the use of ASM prophylaxis in all patients with ICANS, which requires further study to assess its necessity.

Novel Neurocognitive Testing Tool for Early Neurotoxicity Detection Following Anti-CD19 and Anti-BCMA Chimeric Antigen Receptor (CAR) T-cell Therapy: A Pilot Study

BACKGROUND

Immune effector cell-associated neurotoxicity syndrome (ICANS) can be a severe, life-threatening toxicity following CAR T-cell therapy. While currently evaluated by the immune effector cell-associated encephalopathy (ICE) score, not all patients have changes in their ICE score and not all signs and symptoms of neurotoxicity are captured.

METHODS

We conducted a prospective, single center cohort pilot study to evaluate a novel, rapid neurocognitive assessment tool (CART-NS) in detecting early, subtle neurotoxicity prior to the onset of ICANS and any deterioration in the ICE score. CART-NS includes 8 abbreviated forms of neurocognitive tests and 2 symptom questionnaires. Following baseline measurements, CART-NS was administered at 8-hour intervals during the first 30 days after CAR T-cell infusion.

RESULTS

Performance on all measures was significantly lower when patients developed Grade 1 or 2 ICANS (P < .05). Performance on Oral Symbol Digit, Stroop, and the Paced Visual Serial Addition Test was lower between Day 0 and +3 in patients who developed ICANS and persisted even after clinical resolution. Early changes in the Stroop test (AUC = 0.857, 95% CI 0.628-1.000) were most predictive of ICANS onset when measured during the first 36 hour following CAR T-cell infusion. Significant elevations in CRP, G-CSF, GM-CSF, IFNγ, IL-10, IL-15, IL-27, and MIG/CXCL-9 were associated with ICANS development.

CONCLUSION

Brief neurocognitive testing can be feasibly applied for the early detection of ICANS after CAR T-cell therapy, predict which patients may go on to develop ICANS in the first 30 days, and overcome limitations of the ICE assessment tool.

CAR-T cell therapy in rheumatic diseases: a review article

CAR-T cell therapy, a pioneering immune-modulating treatment that was initially designed for hematologic malignancies, is now being considered a potential treatment for autoimmune and rheumatic diseases. This method involves genetically engineering T cells to express chimeric antigen receptors (CARs), allowing them to target specific antigens associated with pathogenic immune cells. The review covers the possibility of CAR-T therapy in the treatment of autoimmune diseases like systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc). The therapy's ability to maintain remission by targeting autoreactive B cells in the course of disease has been an important aspect of studies involving SLE. In refractory RA, CAR-T cells also demonstrate a potential therapeutic modality in selectively killing immune cells driving the disease process. For SSc, CAR-T therapy may represent a novel therapeutic approach because it targets the dysregulated activity of B cells as well as the fibrotic processes that drive the disease pathology. Emerging evidence suggests potential applications in conditions such as Sjögren's syndrome and dermatomyositis. While CAR-T therapy promises accuracy, persistence, and the potential for long-term remission, many problems remain, including the risk of cytokine release syndrome, immune toxicity, and treatment affordability. The development of CAR-Tregs and advanced gene-editing techniques may increase the specificity and safety of therapy. In addition, clinical trials and long-term studies should be conducted to establish the efficacy, safety, and economic feasibility of this innovative approach. This review underscores the transformative potential of CAR-T therapy in the management of rheumatic diseases, particularly in refractory cases. Offering targeted immunomodulation with a minimum of systemic immune suppression, CAR-T therapy could redefine therapeutic paradigms and offer hope for improved outcomes in autoimmune diseases.

Neurotoxic complications of chimeric antigen receptor (CAR) T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy has revolutionised the treatment of haematological malignancies and has demonstrated efficacy in early trials for solid tumours, neurological and rheumatological autoimmune diseases. However, CAR-T is complicated in some patients by neurotoxicity syndromes including immune-effector cell-associated neurotoxicity syndrome, and the more recently described movement and neurocognitive treatment-emergent adverse events, and tumour inflammation-associated neurotoxicity. These neurotoxic syndromes remain poorly understood and are associated with significant morbidity and mortality. A multidisciplinary approach, including neurologists, haematologists and oncologists, is critical for the diagnosis and management of CAR-T neurotoxicity. This approach will be of increasing importance as the use of CAR-T expands, its applications increase and as novel neurotoxic syndromes emerge.

Siltuximab for the treatment of early complications after chimeric antigen receptor T-cell therapy for acute lymphoblastic leukemia in children, adolescents, and young adults

BACKGROUND

Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) are complications associated with CAR T-cell therapy. Siltuximab directly binds interleukin-6 (IL-6) and may be safe and effective as first-line therapy for CRS or ICANS.

METHODS

A retrospective study was conducted on pediatric, adolescent and young adult (AYA) patients treated with siltuximab after CAR T-cell therapy for B-ALL.

RESULTS

A total of 118 patients treated were included: 97 patients developed CRS (82%), and 26 patients (22%) developed ICANS. Sixty-five of those that developed CRS (55%), received treatment. In 46/65 (71%), tocilizumab was administered as anti-IL-6 drug, and 19/65 (29%) patients received siltuximab to treat tocilizumab-refractory CRS (n = 13, 68%), or as first-line CRS treatment (n = 6, 32%). Nine patients treated with siltuximab (47%) developed ICANS. With a median follow-up of 12.1 months, 7 patients remained alive.

CONCLUSIONS

To the best of our knowledge, we present the largest reported cohort of patients treated with siltuximab for CRS following CAR T-cell therapy for B-ALL. Siltuximab's safety profile and its inhibition of IL-6 effects suggest that it should be investigated as first-line therapy in prospective clinical trials.

Unveiling Cognitive Impairment in Older Adults with Cancer on Systemic Anticancer Therapy: A Comprehensive Review

Cancer-related cognitive impairment significantly affects cancer management and decision-making. While the exact mechanisms underlying cancer-related cognitive dysfunction remain complex and multifaceted, different factors have been identified that may help predict which patients are at increased risk for cognitive decline. In this article, we provide a comprehensive overview of systemic cancer therapy-induced cognitive impairment in older adults, including signs and symptoms, diagnosis, and management. In addition, we discuss the evidence available on the impact of endocrine therapy, cytotoxic chemotherapy, immunotherapy and targeted agents on cognition in this population.

A viral infection prediction model for patients with r/r B-cell malignancies after CAR-T therapy: a retrospective analysis

Background

Chimeric antigen receptor T cell (CAR-T) therapy for relapsed/refractory (r/r) B cell acute lymphoblastic leukemia (B-ALL) and B cell non-Hodgkin lymphoma (B-NHL) patients has shown promising effects, but side effects such as viral infections have been observed.

Methods

A total of 45 patients with r/r B-ALL and r/r B-NHL were included in this retrospective study. Patient demographics were recorded, with the primary endpoint being viral infection within 3 months post CAR-T treatment. Univariate and multivariate logistic regression analyses and least absolute shrinkage and selection operator (LASSO) regression analysis were used to analyze independent factors. The patients were divided into a training cohort of 28 and a validation cohort of 17 to construct a prediction model based on determined independent factors. The model's discrimination and calibration were assessed using the receiver operating characteristic curve (ROC), calibration plot, and decision curve analysis (DCA curve).

Results

The univariate and multivariate logistic regression analyses of the 43 patients showed that low baseline lymphocyte ratio was an independent risk factor and using granulocyte colony-stimulating factor (G-CSF) early was a protective factor for viral infection after CAR-T therapy in patients with B-ALL and B-NHL. Based on that, the area under the ROC curve (AUC) of the training cohort and validation cohort was 0.935 (95% CI 0.837-1.000) and 0.869 (95%CI 0.696-1.000), respectively, showing excellent predictive value.

Conclusions

We established a nomogram to predict the factors' influence on viral infection after CAR-T therapy and found that the ratio of baseline lymphocytes and using G-CSF early or lately were able to predict viral infection after CAR-T therapy in r/r B-ALL and B-NHL.

Brain MRI changes in children and young adults with B-cell acute lymphoblastic leukemia following chimeric antigen receptor T-cell therapy

OBJECTIVE

To evaluate brain MRI findings in children and young adults after chimeric antigen receptor (CAR) T-cell therapy for B-cell acute lymphoid leukemia (B-ALL) and associate results with clinical and neurological symptoms.

METHODS

We reviewed pre- and post-CAR-T cell therapy brain MRIs of B-ALL patients aged 25 years or younger who underwent therapy between April 2015 and October 2023 at a single institution. MRI abnormalities were categorized as no change, exacerbation of preexisting lesion, or newly developed lesion. Clinical CAR-mediated toxicities, including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) grades, were recorded. Patients were grouped into those with and without 'exacerbated/new lesion,' and clinical and neurological symptoms were compared using Fisher's exact test.

RESULTS

Sixteen patients with pre- and post-CAR brain MRIs (median age 16 years [interquartile range, 11-21]; 9 males, 7 females) were included in the analysis. Post-CAR brain abnormalities were observed in 81% (13/16) of patients, including white matter (WM) signal changes (12/16), leptomeningeal enhancement (1/16), and cerebellar embolic infarction (1/16). Of the post-CAR WM lesions, 50% (6/12) were exacerbated, 33% (4/12) were newly developed, and 17% (2/12) remained unchanged compared to pre-CAR brain MRI. No difference in CRS (p = 0.079) or ICANS grades (p > 0.99) was observed between patients with and without 'exacerbated/new lesions'.

CONCLUSION

Children and young adults with B-ALL can develop brain MRI abnormalities after CAR T-cell therapy, predominantly WM signal changes. These brain abnormalities did not show an association with higher CRS or ICANS grade.

KEY POINTS

Question Brain MRI findings after chimeric antigen receptor (CAR) T-cell therapy for B-cell acute lymphoid leukemia (B-ALL) and their association with clinical and neurological symptoms are not well understood. Findings Brain MRI abnormalities, mostly white matter changes, were seen in 81% of patients but were not associated with CAR-mediated toxicities. Clinical relevance Brain MRI abnormalities, commonly observed post-CAR T-cell therapy, do not correlate with the severity of CAR-related toxicities, aiding in the clinical management and monitoring of these patients.

Mitigation and Management of Common Toxicities Associated with the Administration of CAR-T Therapies in Oncology Patients

Chimeric antigen receptor T-cell (CAR-T) therapies are one of the main approaches among targeted cellular therapies. Despite the potential benefit and durable responses observed in some patients receiving CAR-T therapies, serious and potentially fatal toxicities remain a major challenge. The most common CAR-T-associated toxicities include cytokine release syndrome (CRS), neurotoxicity, cytopenias, and infections. While CRS and neurotoxicity are generally managed with tocilizumab and corticosteroids, respectively, high-grade toxicities can be life-threatening. Close postinfusion monitoring and assessment of clinical laboratory parameters, patient-related and clinical risk factors (e.g., age, tumor burden, comorbidities, baseline laboratory parameters, and underlying abnormalities), and therapy-related risk factors (e.g., CAR-T type, dose, and CAR-T-induced toxicity) are effective strategies to mitigate the toxicities. Clinical laboratory parameters, including various cytokines, have been identified for CRS (interleukin [IL]-1, IL-2, IL-5, IL-6, IL-8, IL-10, C-reactive protein [CRP], interferon [IFN]-γ, ferritin, granulocyte-macrophage colony-stimulating factor [GM-CSF], and monocyte chemoattractant protein-1), neurotoxicity (IL-1, IL-2, IL-6, IL-15, tumor necrosis factor [TNF]-α, GM-CSF, and IFN-γ), cytopenias (IL-2, IL-4, IL-6, IL-10, IFN-γ, ferritin, and CRP), and infections (IL-8, IL-1β, CRP, IFN-γ, and procalcitonin). CAR-T-associated toxicities can be monitored and treated to mitigate the risk to patients. Assessment of alterations in clinical laboratory parameter values that are correlated with CAR-T-associated toxicities may predict development and/or severity of a given toxicity, which can improve patient management strategies and ultimately enable the patients to better tolerate these therapies.

Immunotherapy-related neurotoxicity in the central nervous system of children with cancer

Significant gaps remain in our understanding of immunotherapy-related neurotoxicity in pediatric patients, largely because much of our knowledge comes from studies in adults. Accurately identifying the adverse effects of immunotherapy in children is also challenging, owing to variations in terminology and grading systems. Moreover, the manifestation of immunotherapy-related neurotoxicity differs greatly across different diseases, various modalities, dosages, and delivery methods. Combining immunotherapy with other treatments might improve outcomes but introduces new complexities and potential for increased toxicities. Additionally, pediatric patients with intracranial malignancy have unique responses to immunotherapies and distinct neurotoxicity compared to those with extracranial malignancy. Consequently, we must enhance our understanding of the pathophysiology, prevalence, severity, and management of immunotherapy's neurotoxic effects in this vulnerable group. This review consolidates the current knowledge of immunotherapy-related neurotoxicity in pediatric oncology, highlighting various types of neurotoxicity including cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), and tumor inflammation-associated neurotoxicity (TIAN), among others. Furthermore, we examine the unique features of neurotoxicity associated with adoptive cellular therapy (ACT), antibody-based therapies, immune checkpoint inhibitors (ICIs), oncolytic viruses (OV), and cancer vaccines.

Current state and perspectives of CAR T cell therapy in central nervous system diseases

B cell-directed CAR T cell therapy has fundamentally changed the treatment of haematological malignancies, and its scope of application is rapidly expanding to include other diseases such as solid tumours or autoimmune disorders. Therapy-refractoriness remains an important challenge in various inflammatory and non-inflammatory disorders of the CNS. The reasons for therapy failure are diverse and include the limited access current therapies have to the CNS, as well as enormous inter- and intra-individual disease heterogeneity. The tissue-penetrating properties of CAR T cells make them a promising option for overcoming this problem and tackling pathologies directly within the CNS. First application of B cell-directed CAR T cells in neuromyelitis optica spectrum disorder and multiple sclerosis patients has recently revealed promising outcomes, expanding the potential of CAR T cell therapy to encompass CNS diseases. Additionally, the optimization of CAR T cells for the therapy of gliomas is a growing field. As a further prospect, preclinical data reveal the potential benefits of CAR T cell therapy in the treatment of primary neurodegenerative diseases such as Alzheimer's disease. Considering the biotechnological optimizations in the field of T cell engineering, such as extension to target different antigens or variation of the modified T cell subtype, new and promising fields of CAR T cell application are rapidly opening up. These innovations offer the potential to address the complex pathophysiological properties of CNS diseases. To use CAR T cell therapy optimally to treat CNS diseases in the future while minimizing therapy risks, further mechanistic research and prospective controlled trials are needed to assess seriously the disease and patient-specific risk-benefit ratio.

Symptoms of Hematologic Tumors Patients after CAR-T Therapy: A Systematic Review and Meta-Analysis

CONTEXT

Patients with hematologic neoplasms after Chimeric antigen receptor T-cell (CAR-T) therapy have multiple syndromes, with corresponding symptoms.

OBJECTIVES

The review aimed to integrate the severity and incidences of symptoms in these patients, and to investigate the difference of the symptoms among different geographic locations, types of hematological tumors, evaluating instruments, and evaluating time, to provide a theoretical basis for symptom management.

METHODS

A literature search of PubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Internet, SinoMed, VIP, and WANFANG DATA was performed for studies reporting symptom scores or symptom incidences of these patients published before November 9, 2023. Heterogeneity between studies was assessed by Higgins' I2. A random effects model was used for studies with I2 > 50%. Methodological quality of included studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklist.

RESULTS

Eight studies were included. Among the reported symptoms, sleep disturbance, fatigue and depression were of higher severity, with the standardized scores exceeding 50. Sadness, problem with concentration, problem with memory, cough and nausea were the top five symptoms in incidence, which exceeded 50%. The symptom scores and incidences assessed by the patient-reported outcomes were higher. Within 90 days of CAR-T infusion, these patients reported a significantly higher severity and incidence of multiple symptoms.

CONCLUSION

Patients with hematologic neoplasms treated by CAR-T suffer from multiple symptoms, including depression, fatigue, and so on. Instruments used to evaluate symptoms and the evaluating time may influence the outcome of symptom assessment.

Critical care considerations of chimeric antigen receptor (CAR) T-cell therapy

Chimeric Antigen Receptor (CAR) T-cell therapies represents a major advancement in the treatment of refractory hematologic malignancies, with high remission rates for relapsed B-cell lymphomas and leukemias. However, it is associated with a broad spectrum of potentially life-threatening toxicities, many of which require intensive care unit (ICU) management. Key complications include Cytokine Release Syndrome (CRS) and Immune Effector Cell-associated Neurotoxicity Syndrome (ICANS), as well as severe infections, Immune Effector Cell-associated Hematotoxicity (ICAHT), coagulopathies, and organ dysfunctions resulting from the intense inflammatory response induced by CAR T-cells. Approximately one third of patients undergoing CAR T-cell therapy require ICU admission. Among those patients, CRS is the leading indication. ICANS and sepsis are other major causes of admission to the ICU. This review provides a comprehensive overview of ICU considerations for managing CAR T-cell-related toxicities, covering criteria for ICU admission, approaches to grading and treating complications, and interdisciplinary recommendations to optimize patient outcomes. Enhanced awareness and early intervention are critical in reducing ICU mortality and improving overall survival in patients receiving CAR T-cell therapy.

Simple and early prediction of severe CAR-T-related adverse events after Axi-cel infusion by initial high fever

Chimeric antigen receptor T-cell (CAR-T)-related adverse events (CAR-AEs), such as immune effector cell-associated neurotoxicity syndrome (ICANS) and cytokine release syndrome (CRS), can be life-threatening and may require high-dose steroids. Identifying patients at high risk for severe CAR-AEs in a simplified way is crucial for early therapeutic intervention. This retrospective study analyzed 44 patients treated with axicabtagene ciloleucel (Axi-cel) to identify predictive factors for severe CAR-AEs. We found that grade ≥ 3 ICANS, hemophagocytic syndrome, and ICU admission were associated with a greater need for high-dose steroids, which we defined as events associated with high-dose steroids (EHS). The incidence of EHS was significantly higher in patients who developed an initial fever (≥ 38.6 °C) within 24 h of CAR-T infusion (p < 0.001). Progression-free survival (PFS) was significantly shorter in patients with EHS compared to those without EHS (p < 0.001). Additionally, patients who developed a fever within 24 h and those with a peak fever of ≥ 38.6 °C both tended to have higher peak CAR-T counts compared to other patients. Our findings suggest that an initial fever (≥ 38.6 °C) within 24 h of Axi-cel infusion may predict severe CAR-AEs requiring high-dose steroids, and that EHS is associated with worse PFS.

Cytokine-mediated increase in endothelial-leukocyte interaction mediates brain capillary plugging during CAR T cell neurotoxicity

CD19-directed CAR T cells treat cancer, but also cause immune effector cell associated neurotoxicity syndrome (ICANS). Despite strong epidemiologic links between cytokine release syndrome and ICANS, it is uncertain how elevated systemic cytokines and activated immune cells cause brain dysfunction. We previously showed that leukocytes plug brain capillaries in an immunocompetent mouse model of CD19-CAR neurotoxicity. Here, we used the same model to explore how integrin activation and endothelial adhesion molecule expression contribute to capillary plugging. In vivo two-photon imaging revealed increased expression of ICAM-1 on brain capillaries, with spatially restricted VCAM-1 increases. TNF, IFN-γ, and IL-1β at concentrations equivalent to CAR T cell patient blood levels upregulated ICAM-1 and VCAM-1 in brain microendothelial cells. In mice, CAR T cells strongly upregulated VLA-4 (integrin α4β1) affinity to VCAM-1, but not affinity of LFA-1 (integrin αLβ2) to ICAM-1. Blocking integrin α4 but not integrin αL improved ICANS behavior in mice. In human CAR T cell patients, increased soluble ICAM-1 and VCAM-1 are associated with ICANS, and integrin α4 but not integrin αL is upregulated in CAR T cells after infusion. Our study highlights that cytokine-driven upregulation of endothelial-leukocyte adhesion may be sufficient to induce neurovascular dysfunction in CAR T cell patients.

Infections in Patients with Solid Tumors Undergoing Adoptive Cellular Therapy

Adoptive cellular therapy (ACT) is an increasingly widely used treatment approach for malignancy. While infectious complications of ACT have been well described in patients with hematologic malignancies, limited data are available on the epidemiology of infections in patients with solid tumors. The purpose of this study was to describe the epidemiology of infections occurring within the first 180 days in adult patients with solid tumors treated with ACT and to identify risk factors predisposing these patients to infection. Data on 132 adult patients with solid tumors undergoing ACT between August 2014 and November 2021 at Memorial Sloan Kettering Cancer Center were collected. Infections were documented from the day of ACT infusion through day 180 postinfusion. Overall, 28 of 132 patients (21.2%) experienced 33 infections within the first 30 days of ACT, and 17 of 131 surviving patients (13%) were diagnosed with 24 infections between day 31 and day 180. Infection-related mortality was low. The majority of infections were bacterial. While male gender, older age, Eastern Cooperative Oncology Group (ECOG) performance status (PS) at time of ACT infusion, tocilizumab receipt, and cytokine release syndrome treated with tocilizumab were associated with shorter time to first infection on univariable analysis, only ECOG PS and tocilizumab receipt remained independent risk factors in the multivariable analysis. The proportion of patients with solid tumors experiencing early or late infections after ACT was lower compared to that reported among patients with B cell malignancies after chimeric antigen receptor T cell therapy. Most observed infections were primarily bacterial with low infection-related mortality; the incidence of viral and fungal infections was low. Based on the low frequency and timing of infections relative to neutropenia, antibacterial and antifungal prophylaxis are not likely to be beneficial. ECOG PS ≥2 and tocilizumab receipt were identified as significant predictors for infection after ACT, likely signaling an individual's debilitated state that predisposes to infection. Additional work to parse out confounders is needed to better identify risk factors for infection.

In Situ Bioconjugation of Synthetic Peptides onto Universal Chimeric Antigen Receptor T Cells for Targeted Cancer Immunotherapies

The recent development of modular universal chimeric antigen receptor (CAR) T-cell platforms that use bifunctional adaptor intermediates to redirect engineered T-cell effector function has greatly expanded the capabilities of adoptive T-cell therapy, enabling safer and more comprehensive cancer treatment. However, universal CAR receptor systems rely on unstable transient recognition of tag-coupled intermediates for T-cell activation, and the array of targeting intermediates has been limited to antibodies and small molecules. Addressing these shortcomings, we engineered universal CAR T-cell receptors that can be covalently modified with synthetic biomaterials in vivo by accelerated SpyCatcher003-SpyTag003 chemistry for cancer-cell targeting. SpyCatcher003-modified CARs, nicknamed DB5 CARs, displayed fast, low-nanomolar reaction kinetics with a synthetic αvβ6-binding peptide that incorporates a SpyTag003 peptide via branched peptide synthesis to comprise a bifunctional intermediate. Prearming DB5 CAR T cells or prelabeling target cells with the bifunctional peptide produced selective CD4+ and CD8+ CAR T-cell responses against αvβ6+ cancer cells in vitro. Furthermore, the synthetic targeting intermediate showed robust DB5 CAR T-cell arming in vivo and selectively reduced αvβ6+ tumor progression in a dual flank xenograft model. We demonstrate the versatility and therapeutic potential of "Cyborg" CAR T-cell therapies that utilize synthetic biomaterials to direct CAR T-cell activity via highly selective bioconjugation that occurs in vivo.

Results From First-in-Human Phase I Study of a Novel CD19-1XX Chimeric Antigen Receptor With Calibrated Signaling in Large B-Cell Lymphoma

PURPOSE

We designed a CD19-targeted chimeric antigen receptor (CAR) comprising a calibrated signaling module, termed 1XX, that differs from that of conventional CD28/CD3ζ and 4-1BB/CD3ζ CARs. Preclinical data demonstrated that 1XX CARs generated potent effector function without undermining T-cell persistence. We hypothesized that 1XX CAR T cells may be effective at low doses and elicit minimal toxicities.

METHODS

In this first-in-human, phase I, dose escalation and expansion clinical trial, patients with relapsed or refractory large B-cell lymphoma received 19(T2)28z-1XX CAR T cells at four dose levels (DLs), ranging from 25 to 200 × 106.

RESULTS

Twenty-eight patients underwent apheresis and received CAR T cells. Sixteen and 12 patients were treated in the dose escalation and expansion cohorts, respectively. The overall response rate (ORR) was 82% and complete response (CR) rate was 71% in the entire cohort. The lowest dose of 25 × 106 was selected for dose expansion. In 16 patients treated at this DL, 88% achieved ORR and 75% CR. With the median follow-up of 24 months, the 1-year event-free survival was 61% (95% CI, 45 to 82) and 14 patients remain in continuous CR beyond 12 months. In all cohorts, grade ≥3 cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome rates were low at 4% and 7%, respectively. 1XX CAR T-cell products contain a higher proportion of CD8 T cells with memory features, and CAR T-cell persistence has been detected beyond 1-2 years in patients with ongoing remission.

CONCLUSION

The calibrated potency of the 1XX CAR affords excellent efficacy at low cell doses with favorable toxicity profiles and may benefit the treatment of other hematologic malignancies, solid tumors, and autoimmunity.

Comprehensive Review of Early and Late Toxicities in CAR T-Cell Therapy and Bispecific Antibody Treatments for Hematologic Malignancies

Chimeric antigen receptor T-cell (or CAR-T) therapy and bispecific antibodies (BsAbs) have revolutionized the treatment of hematologic malignancies, offering new options for relapsed or refractory cases. However, these therapies carry risks of early complications, such as cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), and delayed issues like graft-versus-host disease (GVHD), infections, and secondary cancers. Effective management requires early diagnosis using advanced biomarkers and imaging, along with prompt interventions involving immunosuppressants, corticosteroids, and cytokine inhibitors. A multidisciplinary approach is essential, integrating hematologists, oncologists, and infectious disease specialists, with emerging strategies like targeted biologics and personalized medicine showing promise in balancing efficacy with toxicity management. Ongoing research is critical to refine diagnostics and treatments, ensuring that these therapies not only extend survival but also improve patients' quality of life. This review provides critical insights for healthcare professionals to quickly recognize and treat complications of CAR-T and BsAbs therapies. By focusing on early detection through biomarkers and imaging and outlining timely therapeutic interventions, it aims to equip the multidisciplinary care team with the knowledge necessary to manage the challenges of these advanced treatments effectively, ultimately optimizing patient outcomes.

Emerging therapies in Multiple Myeloma: Leveraging immune checkpoint inhibitors for improved outcomes

BACKGROUND:

Multiple Myeloma is a hematological malignancy characterized by the proliferation of clonal plasma cells and associated with severe clinical manifestations. Despite advancements in diagnosis and management, Multiple Myeloma remains incurable, necessitating further research into more effective therapies.

AIM:

The primary objective of this review is to provide an informative and critical summary of the Multiple Myeloma microenvironment, and emerging revolutionary therapeutic approaches with potential combination therapy to improve the quality of life for Multiple Myeloma patients.

EMERGING APPROACHES:

Recent advancements in immunotherapy, particularly immune checkpoint inhibitors (ICIs), have shown improvements in immune response against Multiple Myeloma. ICIs target inhibitory pathways such as PD-1/PD-L1 and CTLA-4, potentially overcoming tumor-induced immunosuppression. Combination therapies integrate ICIs with proteasome inhibitors, immunomodulators, and monoclonal antibodies to enhance the anti-tumor immune response. Additionally, Chimeric Antigen Receptor T-cell (CAR-T) therapy has demonstrated effectiveness against Multiple Myeloma, particularly when coupled with ICIs to decrease resistance and relapse.

CHALLENGES:

Although the efficacy of ICIs in treating Multiple Myeloma has been hindered by the complexity of the tumor microenvironment and immune evasion mechanisms, this challenge has led to the exploration of combination therapies. Potential side effects are still a big challenge for newly recognized ICIs and combination treatment.

FUTURE DIRECTIONS:

Investigations of new immune checkpoints and the development of targeted therapies against these markers are in progress, creating possibilities for more personalized and effective treatment strategies. Continuous research and robust clinical trials are needed to comprehend the complex dynamics of the Multiple Myeloma microenvironment to develop revolutionary therapeutic targets.

CAR-T therapy toxicities: the importance of macrophages in their development and possible targets for their management

CAR-T cell therapies have risen to prominence over the last decade, and their indications are increasing with several products approved as early as second line in Large B Cell non-Hodgkin Lymphomas. Their major toxicities are the cytokine release syndrome (CRS) and the Immune-effector Cell Associated Neurotoxicity Syndrome (ICANS). These entities involve a hyperinflammatory cascade which is amplified through the mononuclear phagocytic system (MPS). Herein, we review the immune mediated adverse events related to CAR therapy, including their pathophysiologies, and current therapies. In particular, we discuss the emerging role of the MPS in both the toxicity and efficacy of CAR-T therapy, and possible avenues for the modulation of the MPS to optimize efficacy while minimizing toxicity.

Siltuximab for chimeric antigen receptor T-cell therapy-related CRS and ICANS: a multicenter retrospective analysis

ABSTRACT

Chimeric antigen receptor T-cell (CAR-T) therapies are effective in many hematologic malignancies; however, adverse events including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) can affect a significant number of patients. Those who develop refractory CRS or ICANS have few treatment options. Siltuximab, a monoclonal antibody binding circulating interleukin-6, has been proposed to have clinical activity in both CRS and ICANS. We conducted a multicenter retrospective analysis of siltuximab treatment for CRS and ICANS after CAR-T therapy in a real-world cohort from 6 academic centers. Fifty-four patients were evaluated. Sixteen patients had CRS previously treated with tocilizumab and 17 patients had ICANS previously treated with steroids. Of the patients with CRS at the time of siltuximab, 75% had improvement in CRS grade. Of the patients with ICANS at the time of siltuximab, 60% had improvement in ICANS grade. To our knowledge, this is the largest cohort of patients treated with siltuximab for CRS and/or ICANS after CAR-T therapies. Siltuximab appeared to be effective for both CRS and ICANS, including previously treated toxicities. These data support the use of siltuximab in CRS and ICANS as well as provide rationale for future prospective studies.

Advances in Vaccines, Checkpoint Blockade, and Chimeric Antigen Receptor-Based Cancer Immunotherapeutics

Increase in cancer cases and research driven by understanding its causes, facilitated development of novel targeted immunotherapeutic strategies to overcome nonspecific cytotoxicity associated with conventional chemotherapy and radiotherapy. These target specific immunotherapeutic regimens have been evaluated for their efficacy, including: (1) vaccines harnessing tumor specific/associated antigens, (2) checkpoint blockade therapy using monoclonal antibodies against PD1, CTLA-4 and others, and (3) adoptive cell transfer approaches viz. chimeric antigen receptor (CAR)-cell-based therapies. Here, we review recent advancements on these target specific translational immunotherapeutic strategies against cancer/s and concerned limitations.

Evaluation of central nervous system involvement in patients undergoing chimeric antigen receptor-engineered T-cell therapy by magnetic resonance imaging

Chimeric antigen receptor-engineered (CAR) T-cell therapy is an effective immunotherapy for aggressive hematologic cancers. However, it can lead to complications such as immune effector cell-associated neurotoxicity syndrome (ICANS), or complications related to the immunosuppressive status of these patients. The role of imaging in this context is essential to help in ICANS diagnosis and to rule out other potential diagnosis, such as central nervous system infections. Two cases are presented to illustrate this clinical problem. CASE 1: describes a 38-year-old patient with diffuse large B-cell lymphoma who developed ICANS after CAR T-cell therapy. MRI revealed signs of leukoencephalopathy. Case 2 involves a 57-year-old patient with mantle-cell lymphoma who presented neurologic symptoms -clinically suggestive of ICANS- after CAR-T therapy. MRI showed signs indicative of limbic encephalitis. These two cases highlight the importance of MRI in clinical practice after CAR T-Cell Therapy underscoring the role of MRI in the diagnosis of complications in patients with neuropsychiatric symptoms.

Extracorporeal cytokine adsorption as therapeutic option for immune effector cell-associated neurotoxicity syndrome

With the rising number of patients receiving chimeric antigen receptor T-cells, the treatment of this therapy's complications is of growing concern to intensivists and neurologists. We used extracorporeal cytokine adsorption as an add-on therapy in a patient suffering from immune effector cell-associated neurotoxicity syndrome. Interleukin-6 level, which as a readily available parameter is generally used to evaluate course of disease, was rapidly reduced using this method. The patient made a full recovery and is still in hematological remission.

Utility of CSF IL-6 monitoring in managing ICANS associated with Epcoritamab treatment: a case report and literature review

Immune effector cell-associated neurotoxicity syndrome (ICANS) is a serious complication observed in patients receiving advanced immunotherapies such as bispecific antibodies and CAR-T cell therapies. Although the Immune Effector Cell-Associated Encephalopathy (ICE) score is commonly used to assess ICANS severity, its diagnostic accuracy can be compromised by factors such as concomitant medications, underlying comorbidities, and other external influences. This case report discusses a patient with diffuse large B-cell lymphoma who developed ICANS while receiving Epcoritamab. Notably, elevated interleukin-6 (IL-6) levels in the cerebrospinal fluid (CSF) correlated with the patient's clinical course of neurotoxicity. In contrast to conventional scoring systems, which can be affected by unrelated factors, CSF IL-6 levels appeared to more directly reflect the severity and progression of ICANS. These findings are consistent with similar reports from patients treated with CAR-T cells, suggesting that CSF IL-6 may serve as a reliable marker for ICANS progression. Further research that systematically measures CSF IL-6 in diverse clinical contexts could help validate its role as a biomarker, enhancing diagnostic precision and guiding optimal management strategies for ICANS.

Neuropsychiatric manifestations following chimeric antigen receptor T cell therapy for cancer: a systematic review of clinical outcomes and management strategies

BACKGROUND

Chimeric antigen receptor (CAR)-T cell therapy has emerged as a transformative modality in the treatment of patients with cancer. However, it is increasingly evident that this therapeutic approach is not without its challenges. The unique nature of CAR-T cells as living drugs introduces a distinct set of side effects. As the application of CAR-T cell therapy expands to treat a broader range of diseases, it becomes increasingly important to devise effective strategies for handling the associated toxicities. Challenges in treating patients with CAR-T cells include addressing complications such as cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and cytopenias. This comprehensive review seeks to systematically identify, categorize and elucidate all previously described neurological and psychological side effects associated with CAR-T cell therapy, shedding light on the pertinent laboratory findings that underscore these phenomena.

METHODS

PubMed, Springer Link, and ScienceDirect were systematically searched for empirical studies on adult patients with cancer receiving CAR-T cell therapy for hemato-oncological malignancies. Quality assessment was conducted using Version 2 of the Cochrane risk-of-bias tool (RoB 2) for randomized trials and adherence to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) checklist for observational studies. The synthesis of findings was conducted via a narrative approach, consolidating the diverse array of data into a coherent framework.

RESULTS

From an initial pool of 2,276 citations, 546 studies met the inclusion criteria, exhibiting a rich tapestry of heterogeneity in terms of study characteristics and patient samples. The incidence of neuropsychological symptoms varied notably across different CAR-T cell products and hematological malignancies. Among the most frequently reported neuropsychological symptoms were aphasia, attention deficits, impaired consciousness, and disorientation, alongside a constellation of other symptoms including confusion, cognitive impairment, memory loss, writing difficulties, fatigue, headache, agitation, tremor, seizures, and psychomotor retardation. Early intervention strategies, including corticosteroids and tocilizumab, have shown the potential to reduce the intensity of neuropsychological symptoms and prevent their progression to critical complications.

CONCLUSION

These insights underscore the imperative of extending neuropsychological assessments beyond the conventional Immune Effector Cell-Associated Encephalopathy score framework.

CAR-T cell therapy for the treatment of adult high-grade gliomas

Treatment for malignant primary brain tumors, including glioblastoma, remains a significant challenge despite advances in therapy. CAR-T cell immunotherapy represents a promising alternative to conventional treatments. This review discusses the landscape of clinical trials for CAR-T cell therapy targeting brain tumors, highlighting key advancements like novel target antigens and combinatorial strategies designed to address tumor heterogeneity and immunosuppression, with the goal of improving outcomes for patients with these aggressive cancers.

Targeting pivotal amino acids metabolism for treatment of leukemia

Metabolic reprogramming is a crucial characteristic of cancer, allowing cancer cells to acquire metabolic properties that support their survival, immune evasion, and uncontrolled proliferation. Consequently, targeting cancer metabolism has become an essential therapeutic strategy. Abnormal amino acid metabolism is not only a key aspect of metabolic reprogramming but also plays a significant role in chemotherapy resistance and immune evasion, particularly in leukemia. Changes in amino acid metabolism in tumor cells are typically driven by a combination of signaling pathways and transcription factors. Current approaches to targeting amino acid metabolism in leukemia include inhibiting amino acid transporters, blocking amino acid biosynthesis, and depleting specific amino acids to induce apoptosis in leukemic cells. Different types of leukemic cells rely on the exogenous supply of specific amino acids, such as asparagine, glutamine, arginine, and tryptophan. Therefore, disrupting the supply of these amino acids may represent a vulnerability in leukemia. This review focuses on the pivotal role of amino acids in leukemia metabolism, their impact on leukemic stem cells, and their therapeutic potential.

Evolving strategies for addressing CAR T-cell toxicities

The field of chimeric antigen receptor (CAR) T-cell therapy has grown from a fully experimental concept to now boasting a multitude of treatments including six FDA-approved products targeting various hematologic malignancies. Yet, along with their efficacy, these therapies come with side effects requiring timely and thoughtful interventions. In this review, we discuss the most common toxicities associated with CAR T-cells to date, highlighting risk factors, prognostication, implications for critical care management, patient experience optimization, and ongoing work in the field of toxicity mitigation. Understanding the current state of the field and standards of practice is critical in order to improve and manage potential toxicities of both current and novel CAR T-cell therapies as they are applied in the clinic.

The advent of chimeric antigen receptor T Cell therapy in recalibrating immune balance for rheumatic autoimmune disease treatment

CAR-T cell therapy, a cutting-edge cellular immunotherapy with demonstrated efficacy in treating hematologic malignancies, also exhibits significant promise for addressing autoimmune diseases. This innovative therapeutic approach holds promise for achieving long-term remission in autoimmune diseases, potentially offering significant benefits to affected patients. Current targets under investigation for the treatment of these conditions include CD19, CD20, and BCMA, among others. However, CAR-T therapy faces difficulties such as time-consuming cell manufacturing, complex and expensive process, and the possibility of severe adverse reactions complicating the treatment, etc. This article examines CAR-T therapy across various rheumatic autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren's syndrome (SS), systemic sclerosis (SSc), antisynthetase syndrome (ASS), and ANCA-associated vasculitis (AAV), highlighting both therapeutic advancements and ongoing challenges.

A Pathologist's Guide to Non-clinical Safety Assessment of Adoptive Cell Therapy Products

Through two decades of research and development, adoptive cell therapies (ACTs) have revolutionized treatment for hematologic malignancies. Many of the seven US Food and Drug Administration (FDA)-approved products are proven to be a curative last line of defense against said malignancies. The ACTs, known more commonly as chimeric antigen receptor (CAR) T-cells, utilize engineered lymphocytes to target and destroy cancer cells in a patient-specific, major histocompatibility complex (MHC)-independent manner, acting as "living drugs" that adapt to and surveil the body post-treatment. Despite their efficacy, CAR T-cell therapies present unique challenges in preclinical safety assessment. The safety and pharmacokinetics of CAR T-cells are influenced by numerous factors including donor and recipient characteristics, product design, and manufacturing processes that are not well-predicted by existing in vitro and in vivo preclinical safety models. The CAR therapy-mediated toxicities in clinical settings primarily arise from unintended targeting of non-tumor cells, potential tumorigenicity, and severe immune activation syndromes like cytokine release syndrome and immune effector cell-associated neurotoxicity. Addressing these issues necessitates a deep understanding of CAR target expression in normal tissues, inclusive of the spatial microanatomical distribution, off-target screening, and a deep understanding CAR cell manufacturing practices and immunopathology.

Management of Toxicities Associated with BCMA, GPRC5D, and FcRH5-Targeting Bispecific Antibodies in Multiple Myeloma

PURPOSE OF REVIEW

The introduction of bispecific antibodies is one of the most significant recent advances in the treatment of relapsed/refractory multiple myeloma. This review will summarize the management of the toxicities associated with newly approved T cell-engaging bispecific antibodies and those which may be approved in the near future.

RECENT FINDINGS

Numerous trials have shown that bispecific antibodies can be both effective and tolerable when adverse events are properly managed. Cytokine release syndrome and increased infections are observed across all bispecific antibodies. Additional adverse events are target-specific, such as the more severe hypogammaglobulinemia and infections of BCMA bispecific antibodies and the dysgeusia, nail dystrophy, and skin changes of GPRC5D bispecific antibodies. Bispecific antibodies will surely become a mainstay of multiple myeloma therapy given their efficacy and accessibility. Their unique toxicities must be carefully considered and managed to ensure they are utilized safely.

Therapeutic potential of EVs loaded with CB2 receptor agonist in spinal cord injury via the Nrf2/HO-1 pathway

BACKGROUND

Spinal cord injury (SCI) poses a challenge due to limited treatment options. Recently, the effect and mechanism of Exo-loaded cannabinoid receptor type 2 (CB2) agonist AM1241(Exo + AM1241) have been applied in other inflammatory diseases but not in SCI.

METHODS

The SCI model was set up using C57BL/6 mice, followed by the treatment of Exo, AM1241, and Exo + AM1241. We assessed the effects of the following treatments on motor function recovery using BMS, and evaluated histological changes, apoptosis activity, inflammation, and oxidative stress in the SCI mice model. Additionally, the effect of following treatments on spinal cord neural stem cells (NSCs) was evaluated under lipopolysaccharides (LPS) induced inflammatory and oxidative models and, glutamate (Gluts) induced cell apoptosis models.

RESULT

Our results demonstrated that Exo + AM1241 treatment significantly improved motor function recovery, after SCI by decreasing proinflammatory cytokines, and suppressing astrocyte/microglia (GFAP/Iba1) activation in the injury zone. Additionally, this treatment reduces pro-apoptotic proteins (Bax and caspase 3), increases the levels of the anti-apoptotic protein Bcl-2, enhances antioxidant defenses by boosting SOD and GSH, and lowers oxidative stress markers such as MDA. It also activates the Nuclear factor erythroid-2 (Nrf2) related factor 2 signaling pathway, thereby enhancing tissue protection against damage and cell death.

Novel immunotherapeutic approaches in gastric cancer

Gastric cancer is a malignant tumor that ranks third in cancer-related deaths worldwide. Early-stage gastric cancer can often be effectively managed through surgical resection. However, the majority of cases are diagnosed in advanced stages, where outcomes with conventional radiotherapy and chemotherapy remain unsatisfactory. Immunotherapy offers a novel approach to treating molecularly heterogeneous gastric cancer by modifying the immunosuppressive tumor microenvironment. Immune checkpoint inhibitors and adoptive cell therapy are regarded as promising modalities in cancer immunotherapy. Food and Drug Administration-approved programmed death-receptor inhibitors, such as pembrolizumab, in combination with chemotherapy, have significantly extended overall survival in gastric cancer patients and is recommended as a first-line treatment. Despite challenges in solid tumor applications, adoptive cell therapy has demonstrated efficacy against various targets in gastric cancer treatment. Among these approaches, chimeric antigen receptor-T cell therapy research is the most widely explored and chimeric antigen receptor-T cell therapy targeting claudin18.2 has shown acceptable safety and robust anti-tumor capabilities. However, these advancements primarily remain in preclinical stages and further investigation should be made to promote their clinical application. This review summarizes the latest research on immune checkpoint inhibitors and adoptive cell therapy and their limitations, as well as the role of nanoparticles in enhancing immunotherapy.

Cytokines in hematopoietic cell transplantation and related cellular therapies

Cytokines are pleiotropic molecules involved in hematopoiesis, immune responses, infections, and inflammation. They play critical roles in hematopoietic cell transplantation (HCT) and immune effector cell (IEC) therapies, mediating both therapeutic and adverse effects. Thus, cytokines contribute to the immunopathology of graft-versus-host disease (GVHD), cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). This review examines cytokine functions in these contexts, their influence on engraftment and immune recovery post-transplantation, and their role in mediating toxicities. We focus on current and potential uses of cytokines to enhance engraftment and potentiate IEC therapies, as well as strategies to mitigate cytokine-mediated complications using cytokine blockers (e.g., tocilizumab, anakinra) and JAK inhibitors (e.g., ruxolitinib). We discuss new insights into GVHD physiology that have led to novel treatments, such as CSF1R blockade, which is effective in refractory chronic GVHD.

CAR-T Cells for the Treatment of Central Nervous System Tumours: Known and Emerging Neurotoxicities

The advent of chimeric antigen receptor (CAR)-T cells has recently changed the prognosis of relapsing/refractory diffuse large B-cell lymphomas, showing response rates as high as 60 to 80%. Common toxicities reported in the pivotal clinical trials include the cytokine release syndrome (CRS) and the Immune effector Cell-Associated Neurotoxicity Syndrome (ICANS), a stereotyped encephalopathy related to myeloid cell activation and blood-brain barrier dysfunction, presenting with a distinctive cascade of dysgraphia, aphasia, disorientation, attention deficits, vigilance impairment, motor symptoms, seizures, and diffuse brain oedema. The tremendous oncological efficacy of CAR-T cells observed in systemic B-cell malignancies is leading to their growing use in patients with primary or secondary central nervous system (CNS) lymphomas and in patients with solid tumours, including several CNS cancers. Early studies conducted in adult and paediatric patients with solid CNS tumours reported a distinct profile of neurotoxicity referred to as Tumour inflammation-associated neurotoxicity (TIAN), corresponding to local inflammation at the tumour site manifesting with focal neurological deficits or mechanical complications (e.g., obstructive hydrocephalus). The present review summarises available data on the efficacy and safety of CAR-T cells for solid and haematological CNS malignancies, emphasising known and emerging phenotypes, ongoing challenges, and future perspectives.

EEG features and synek scale indicate severity of neurotoxicity in adult patients treated with CD19 CAR T-cell therapy

Patients who develop chimeric antigen receptor (CAR) T-cell-related immune effector cell-associated neurotoxicity syndrome (ICANS) frequently undergo evaluation with electroencephalography (EEG). We hypothesize that EEG features and Synek scale score, a measure of degree of EEG abnormality, are associated with ICANS severity. Here, we performed a retrospective review of 125 adult patients at Memorial Sloan Kettering Cancer Center (MSKCC) who received CAR-T cell therapy from 2010 to 2019, including 53 patients with B-acute lymphoblastic leukemia treated with 1928z CAR T cells (NCT01044069) and 72 patients with large B-cell lymphoma (LBCL) treated with the commercial CAR T products axicabtagene ciloleucel or tisagenlecleucel. We collected video EEG monitoring (27 with B-ALL and 20 with LBCL) and recorded daily EEG features, Synek scores, and ICANS grade for 47 eligible patients. Synek scale and ICANS grade were positively correlated (correlation coefficient 0.47, 95% CI: 0.31-0.60). This was further corroborated in the univariable model associating high Synek scale (3 or 4) with high ICANS grade (OR = 15.2; 95%CI:7.8-29.7, p < 0.0001). EEG features such as discontinuity, absence of posterior dominant rhythm, and presence of generalized sharp waves were statistically significantly associated with higher ICANS grade in univariable models. In the multivariable model, discontinuity (OR = 4.2 (95%CI:1.3-13.8, p = 0.02) and absence of posterior dominant rhythm (OR = 10.5 (95%CI:4.6-23.9, p < 0.0001) were statistically associated with higher ICANS grade. Overall, EEG discontinuity and absence of posterior dominant rhythm were independently associated with higher severity of neurotoxicity. Further, our data suggest that Synek Scale, may be a severity marker for neurotoxicity.

Multicellular Cancer-Stroma Spheres (CSS) for In Vitro Assessment of CAR-T Cell-Associated Toxicity

CAR-T therapy has revolutionized the field of oncology, offering a promising treatment option for cancer patients. However, the significant morbidity associated with therapy-related toxicity presents a major challenge to its widespread use. Despite extensive research into the underlying mechanisms of CAR-T therapy-related toxicity, there are still many unknowns. Furthermore, the lack of adequate in vitro models for assessing immunotoxicity and neurotoxicity further complicates the development of safer cellular therapies. Previously in our laboratory, we developed cancer-stroma spheres (CSS) composed of prostate adenocarcinoma PC3 cells and mesenchymal stem cells (MSC). Herein we present evidence that multicellular CSS could serve as a valuable in vitro model for toxicity studies related to CAR-T therapy. CSS containing CD19-overexpressing PC3M cells exhibited increased secretion of CAR-T cell toxicity-associated IL-8, MCP-1, and IP-10 in the presence of anti-CD19 CAR-T cells, compared to spheres derived from single cell types.

Clinical features, pathophysiology, and management of acute myelopathy following CAR T-cell therapy

ABSTRACT

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of patients with relapsed or refractory hematologic malignancies, but it comes with unique toxicities, notably cytokine release syndrome and ICANS (immune effector cell-associated neurotoxicity syndrome). As experience with CAR T-cell therapy grows, distinct and infrequent neurologic complications are becoming increasingly evident. Recently, reports of acute myelopathy after the administration of CAR T-cell therapies have been accumulating. Despite the establishment of consensus guidelines for managing ICANS, there remains limited guidance on the appropriate investigations and treatments for this rare complication. In this manuscript, we delve into the clinical features, pathophysiology, and strategies for the optimal management of acute myelitis after CAR T-cell therapy and draw insights from reported cases in the literature.

Optimizing CAR-T cell therapy for solid tumors: current challenges and potential strategies

Chimeric antigen receptor (CAR)-T cell therapy demonstrates substantial efficacy in various hematological malignancies. However, its application in solid tumors is still limited. Clinical studies report suboptimal outcomes such as reduced cytotoxicity of CAR-T cells and tumor evasion, underscoring the need to address the challenges of sliding cytotoxicity in CAR-T cells. Despite improvements from fourth and next-generation CAR-T cells, new challenges include systemic toxicity from continuously secreted proteins, low productivity, and elevated costs. Recent research targets genetic modifications to boost killing potential, metabolic interventions to hinder tumor progression, and diverse combination strategies to enhance CAR-T cell therapy. Efforts to reduce the duration and cost of CAR-T cell therapy include developing allogenic and in-vivo approaches, promising significant future advancements. Concurrently, innovative technologies and platforms enhance the potential of CAR-T cell therapy to overcome limitations in treating solid tumors. This review explores strategies to optimize CAR-T cell therapies for solid tumors, focusing on enhancing cytotoxicity and overcoming application restrictions. We summarize recent advances in T cell subset selection, CAR-T structural modifications, infiltration enhancement, genetic and metabolic interventions, production optimization, and the integration of novel technologies, presenting therapeutic approaches that could improve CAR-T cell therapy's efficacy and applicability in solid tumors.

Chimeric antigen receptor T cell therapy for autoimmune disease

Infusion of T cells engineered to express chimeric antigen receptors (CARs) that target B cells has proven to be a successful treatment for B cell malignancies. This success inspired the development of CAR T cells to selectively deplete or modulate the aberrant immune responses that underlie autoimmune disease. Promising results are emerging from clinical trials of CAR T cells targeting the B cell protein CD19 in patients with B cell-driven autoimmune diseases. Further approaches are being designed to extend the application and improve safety of CAR T cell therapy in the setting of autoimmunity, including the use of chimeric autoantibody receptors to selectively deplete autoantigen-specific B cells and the use of regulatory T cells engineered to express antigen-specific CARs for targeted immune modulation. Here, we highlight important considerations, such as optimal target cell populations, CAR construct design, acceptable toxicities and potential for lasting immune reset, that will inform the eventual safe adoption of CAR T cell therapy for the treatment of autoimmune diseases.

Rational Protein Engineering to Enhance MHC-Independent T-cell Receptors

Chimeric antigen receptor (CAR)-based therapies have pioneered synthetic cellular immunity but remain limited in their long-term efficacy. Emerging data suggest that dysregulated CAR-driven T-cell activation causes T-cell dysfunction and therapeutic failure. To re-engage the precision of the endogenous T-cell response, we designed MHC-independent T-cell receptors (miTCR) by linking antibody variable domains to T-cell receptor constant chains. Using predictive modeling, we observed that this standard "cut and paste" approach to synthetic protein design resulted in myriad biochemical conflicts at the hybrid variable-constant domain interface. Through iterative modeling and sequence modifications, we developed structure-enhanced miTCRs which significantly improved receptor-driven T-cell function across multiple tumor models. We found that 41BB costimulation specifically prolonged miTCR T-cell persistence and enabled improved leukemic control in vivo compared with classic CAR T cells. Collectively, we have identified core features of hybrid receptor structure responsible for regulating function. Significance: Improving the durability of engineered T-cell immunotherapies is critical to enhancing efficacy. We used a structure-informed design to evolve improved miTCR function across several models. This work underscores the central role of synthetic receptor structure in T-cell function and provides a framework for improved receptor engineering.

Tocilizumab Prophylaxis Following Axicabtagene Ciloleucel in Relapsed or Refractory Large B-Cell Lymphoma

Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved in patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL). Most patients treated with axi-cel experience cytokine release syndrome (CRS) and/or adverse neurologic events (NEs). To explore potential approaches for reducing CAR T-cell-related toxicities with axi-cel, several safety expansion cohorts were added to the pivotal ZUMA-1 trial. ZUMA-1 Cohort 3 was an exploratory safety cohort that investigated the use of the IL-6 receptor-blocking antibody tocilizumab and anticonvulsant levetiracetam as prophylaxis against CRS and NEs in patients treated with axi-cel. Patients with R/R LBCL were enrolled in Cohort 3 and received conditioning chemotherapy on d -5 through -3 followed by a single infusion of axi-cel (2 × 106 cells/kg) on d 0. Prophylactic tocilizumab (8 mg/kg) was administered 48 h after axi-cel infusion. Primary endpoints were incidence and severity of CRS and NEs. Key secondary endpoints included the incidence of adverse events, objective response rate (ORR), duration of response, progression-free survival, overall survival (OS), and biomarker analyses (eg, circulating CAR T cells, cytokines, chemokines). Forty-two patients were enrolled in Cohort 3, 38 of whom received axi-cel. In the 24-month analysis, any-grade CRS and NEs occurred in 92% and 87% of patients, and Grade ≥3 CRS and NEs occurred in 3% and 42% of patients, respectively. One Grade 5 NE (cerebral edema) occurred. With 24-mo minimum follow-up, the ORR was 63%, and 39.5% of patients had ongoing response. With 48-month follow-up, median OS was 34.8 mo (95% CI, 5.4-not estimable). CAR T-cell expansion in ZUMA-1 Cohort 3 was comparable with pivotal Cohorts 1 and 2. Consistent with tocilizumab-mediated inhibition of IL-6R, serum IL-6 levels were increased relative to Cohorts 1 and 2. Grade ≥3 NEs were associated with elevated IL-6 levels, proinflammatory cytokines, and myeloid cells in the cerebrospinal fluid. Based on these findings, prophylactic tocilizumab is not recommended to prevent CAR T-cell-related adverse events, and beneficial effects of prophylactic levetiracetam remain uncertain in patients with R/R LBCL.

Advancements of engineered live oncolytic biotherapeutics (microbe/virus/cells): Preclinical research and clinical progress

The proven efficacy of immunotherapy in fighting tumors has been firmly established, heralding a new era in harnessing both the innate and adaptive immune systems for cancer treatment. Despite its promise, challenges such as inefficient delivery, insufficient tumor penetration, and considerable potential toxicity of immunomodulatory agents have impeded the advancement of immunotherapies. Recent endeavors in the realm of tumor prophylaxis and management have highlighted the use of living biological entities, including bacteria, oncolytic viruses, and immune cells, as a vanguard for an innovative class of live biotherapeutic products (LBPs). These LBPs are gaining recognition for their inherent ability to target tumors. However, these LBPs must contend with significant barriers, including robust immune clearance mechanisms, cytotoxicity and other in vivo adverse effects. Priority must be placed on enhancing their safety and therapeutic indices. This review consolidates the latest preclinical research and clinical progress pertaining to the exploitation of engineered biologics, spanning bacteria, oncolytic viruses, immune cells, and summarizes their integration with combination therapies aimed at circumventing current clinical impasses. Additionally, the prospective utilities and inherent challenges of the biotherapeutics are deliberated, with the objective of accelerating their clinical application in the foreseeable future.

New avenues for cancer immunotherapy: Cell-mediated drug delivery systems

Cancer research has become increasingly complex over the past few decades as knowledge of the heterogeneity of cancer cells, their proliferative ability, and their tumor microenvironments has become available. Although conventional therapies remain the most compelling option for cancer treatment to date, immunotherapy is a promising way to harness natural immune defenses to target and kill cancer cells. Cell-mediated drug delivery systems (CDDSs) have been an active line of research for enhancing the therapeutic efficacy and specificity of cancer immunotherapy. These systems can be tailored to different types of immune cells, allowing immune evasion and accumulation in the tumor microenvironment. By enabling the targeted delivery of therapeutic agents such as immune stimulants, cytokines, antibodies, and antigens, CDDSs have improved the survival of some patients with cancer. This review summarizes the research status of CDDSs, with a focus on their underlying mechanisms of action, biology, and clinical applications. We also discuss opportunities and challenges for implementation of CDDSs into mainstream cancer immunotherapy.

Cancer Therapy-Induced Encephalitis

Encephalitis associated with cancer therapies is a rare but serious complication that can significantly impact patients' quality of life and it requires prompt identification and management. Over the past two decades, immunotherapy-particularly immune checkpoint inhibitors-has become a cornerstone of cancer treatment, with up to half of metastatic cancer patients in economically developed countries now receiving these therapies. The widespread adoption of immunotherapy has led to improved survival rates and long-term remissions, even in patients with advanced metastatic disease. However, as immune modulators, these therapies can trigger a range of immune-related adverse events, including a variety of novel neurological toxicities. Among these, encephalitis is of particular concern due to its potential severity, which can compromise treatment outcomes. This review aims to provide a comprehensive overview of the literature on this condition, highlighting optimal diagnostic strategies and management approaches to mitigate the risk of significant morbidity, while also comparing encephalitis induced by immunotherapy with that caused by traditional chemotherapies and targeted oncologic treatments.

Effect of 5-Aza-2'-deoxycytidine on T-cell acute lymphoblastic leukemia cell biological behaviors and PTEN expression

Objective

We currently face a sharp increase of T-cell acute lymphoblastic leukemia (T-ALL) incidence and a challenge of unmasking its complex etiology. The deoxycytidine analog 5-Aza-2'-deoxycytidine (5-Aza-dC) is currently the most common nucleoside methyltransferase inhibitor. The objective of this study was to clarify the role of 5-Aza-dC in T-ALL cell biological behaviors and phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression.

Material and Methods

T-ALL cell lines were divided into the experimental group with 5-Aza-dC solution treatment, and the control group without treatment. PTEN methylation was detected using methylation-specific polymerase chain reaction (MS-PCR). Following the measurement of cell proliferation, viability, apoptosis, invasion, migration, etc., quantitative reverse transcription-polymerase chain reaction (PCR) was conducted to detect PTEN, DNA methyl-transferases (DNMT1), DNMT3a, MBD2, and MeCP2 expressions; Western blot to detect PTEN, PI3K, AKT, and mTOR protein expressions. In addition, rescue experiments to inhibit and restore the expression of PTEN in different groups were performed for further identification of the results in the former parts.

Results

MS-PCR results showed that in Jurkat cells, the target band was amplified using methylated primers for the PTEN gene promoter region; moreover, at 10 μmol/L of 5-Aza-dC for 24 h, PTEN methylation was completely removed without any un-methylated band observed. The experimental group had significantly lower cell proliferation and viability rates, higher apoptosis rates, decreased cell proportion in S phase, reduced invasion and migration; increased PTEN expression, decreased DNMT1, DNMT3a, MBD2, and MeCP2 mRNA expressions; and decreased PI3K, AKT, and mTOR protein expressions than those in the control group (all P < 0.05). Furthermore, according to the rescue experiment, silenced PTEN expression weakened the beneficial roles of 5-Aza-dC treatment, and resulted in significantly higher cell proliferation and viability rates, lower apoptosis rates, increased cell proportion in S phase, increased cell invasion and migration; decreased PTEN expression, elevated DNMT1, DNMT3a, MBD2, and MeCP2 mRNA expressions, and higher PI3K, AKT, and mTOR protein expressions (all P < 0.05). While restored PTEN expression enhanced functions of 5-Aza-dC treatment, leading to obviously lower cell proliferation and viability rates, higher apoptosis rates, increased cell proportion in G1 phase, and reduced cell invasion and migration; as well as increased PTEN expression, decreased DNMT1, DNMT3a, MBD2, and MeCP2 mRNA expressions, and lower PI3K, AKT, and mTOR protein expressions (all P < 0.05).

Conclusion

Demethylation treatment with 5-Aza-dC can inhibit T-ALL cell malignant biological behaviors and enhance the sensitivity to chemotherapy agents possibly, which may be related to the inhibited expressions of DNMT1, DNMT3a, MBD2, and MeCP2, and restored expression activity of PTEN to negatively regulate the PI3K/AKT signal transduction. Our silencing and restoration of PTEN expressions further support our findings, highlighting that demethylation with 5-Aza-dC to restore the anti-tumor activity of the tumor suppressor gene PTEN may be a promising therapeutic option for treating T-ALL.