Associations of granulocyte colony-stimulating factor with toxicities and efficacy of chimeric antigen receptor T-cell therapy in relapsed or refractory B-cell acute lymphoblastic leukemia

Few studies have reported the associations of granulocyte colony-stimulating factor (G-CSF) with cytokine release syndrome (CRS), neurotoxic events (NEs) and efficacy after chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We present a retrospective study of 67 patients with R/R B-ALL who received anti-CD19 CAR T-cell therapy, 41 (61.2%) patients received G-CSF (G-CSF group), while 26 (38.8%) did not (non-G-CSF group). Patients had similar duration of grade 3-4 neutropenia between the two groups. The incidences of CRS and NEs were higher in G-CSF group, while no differences in severity were found. Further stratified analysis showed that the incidence and severity of CRS were not associated with G-CSF administration in patients with low bone marrow (BM) tumor burden. None of the patients with low BM tumor burden developed NEs. However, there was a significant increase in the incidence of CRS after G-CSF administration in patients with high BM tumor burden. The duration of CRS in patients who used G-CSF was longer. There were no significant differences in response rates at 1 and 3 months after CAR T-cell infusion, as well as overall survival (OS) between the two groups. In conclusion, our results showed that G-CSF administration was not associated with the incidence or severity of CRS in patients with low BM tumor burden, but the incidence of CRS was higher after G-CSF administration in patients with high BM tumor burden. The duration of CRS was prolonged in G-CSF group. G-CSF administration was not associated with the efficacy of CAR T-cell therapy.

Improving cell reinfusion to enhance the efficacy of chimeric antigen receptor T-cell therapy and alleviate complications

Adoptive cell therapy (ACT) is a rapidly expanding area within the realm of transfusion medicine, focusing on the delivery of lymphocytes to trigger responses against tumors, viruses, or inflammation. This area has quickly evolved from its initial promise in immuno-oncology during preclinical trials to commercial approval of chimeric antigen receptor (CAR) T-cell therapies for leukemia and lymphoma (Jun and et al., 2018) [1]. CAR T-cell therapy has demonstrated success in treating hematological malignancies, particularly relapsed/refractory B-cell acute lymphoblastic leukemia and non-Hodgkin's lymphoma (Qi and et al., 2022) [2]. However, its success in treating solid tumors faces challenges due to the short-lived presence of CAR-T cells in the body and diminished T cell functionality (Majzner and Mackall, 2019) [3]. CAR T-cell therapy functions by activating immune effector cells, yet significant side effects and short response durations remain considerable obstacles to its advancement. A prior study demonstrated that the therapeutic regimen can induce systemic inflammatory reactions, such as cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), tumor lysis syndrome (TLS), off-target effects, and other severe complications. This study aims to explore current research frontiers in this area.

Nursing Considerations for Cytokine Release Syndrome in Relapsed/Refractory Multiple Myeloma: Experience with Teclistamab from the MajesTEC-1 Study

OBJECTIVES

Cytokine release syndrome (CRS) is a systemic inflammatory response that is commonly observed as a class effect of T-cell-redirecting therapies. This article provides important practical guidance for nurses relating to the diagnosis, monitoring, and management of CRS in patients receiving teclistamab, based on experience from the MajesTEC-1 clinical trial and real-life nursing practice.

METHODS

MajesTEC-1 is a phase 1/2 study of teclistamab in heavily pretreated patients with relapsed/refractory multiple myeloma. To mitigate the risk of high-grade CRS, patients were carefully monitored for early signs and symptoms of CRS (including fever, which must have fully resolved before teclistamab administration).

RESULTS

A survey of nurses from several of the study sites provided additional real-life insights into nursing best practices for managing CRS from four academic institutions in three countries.

CONCLUSIONS

In MajesTEC-1, 72% of patients treated with teclistamab experienced CRS, the majority of which was low grade. All cases resolved and none led to treatment discontinuation. Real-life supportive measures for CRS are generally aligned with those outlined in the study.

IMPLICATIONS FOR NURSING PRACTICE

Because nurses are on the frontline of patient care, they play a crucial role in promptly recognizing the signs and symptoms of CRS and responding with timely and appropriate supportive treatment. This review provides important practical guidance for nurses on diagnosis, monitoring, and management of CRS in patients receiving teclistamab, based on experience from the MajesTEC-1 trial and real-life nursing practice.

A novel safer CD19CAR with shRNA interference of IFN-γ can reduce multiple cytokine levels without significantly compromising its killing efficacy

Cytokine release syndrome (CRS) is a great challenge for the application of anti-CD19 CAR-T cell therapy. The aim of this study was to investigate the effect of knocking down interferon gamma (IFN-γ) by shRNA as a potential strategy to reduce the cytokine storms. A newly designed short hairpin interference RNA of IFN-γ (shIFN-γ) in CD19CAR gene was constructed. Several cellular model systems of approach using Nalm-6 cell lines including Nalm-6CD19pos and Nalm-6CD19neg with or without monocytes and endothelial cells were used to analyze the different levels of cytokines after shIFN-γ-anti-CD19CAR-T cell targeted therapy. The activity of this novel CD19CAR-T was evaluated both in vitro and in NSG mouse model. The killing efficacy of shIFN-γ-anti-CD19CAR-T at the E:T ratio of 2:1 was similar to that of regular anti-CD19CAR-T at the E:T ratio of 1:1. The IFN-γ level in the shIFN-γ-anti-CD19CAR-T cell group was (2673.1 ± 307.4) pg/ml at the E:T ratio of 2:1 which was significantly lower than that ((8261.5 ± 345.5) pg/ml) in the regular anti-CD19CAR-T group at the E:T ratio of 1:1. Cytotoxicity experiments in vitro showed significantly reduced concentrations of IFN-γ, IL-6 and TNFα in the shIFN-γ-anti-CD19CAR-T cell group compared to regular anti-CD19CAR-T cell group. Both regular anti-CD19CAR and shIFN-γ-CD19CAR-T exerted bystander killing effect in vitro. We conclude that shIFN-γ-anti-CD19CAR-T cells can reduce the generation of cytokine storms without significantly compromising their therapeutic efficacy in the preclinical setting. In mouse model, 3 × 106 shIFN-γ-anti-CD19CAR-T cells/mouse generated the similar killing efficacy to that with 2 × 106 regular anti-CD19CAR-T cells/mouse.

Mosunetuzumab Safety Profile in Patients With Relapsed/Refractory B-cell Non-Hodgkin Lymphoma: Clinical Management Experience From a Pivotal Phase I/II Trial

BACKGROUND

Mosunetuzumab is a CD20xCD3 T-cell engaging bispecific antibody approved in Europe and the United States for relapsed/refractory (R/R) follicular lymphoma (FL) after ≥ 2 prior therapies.

MATERIALS AND METHODS

We present interim safety data from the mosunetuzumab GO29781 (NCT02500407) phase I/II dose-escalation study in R/R non-Hodgkin lymphoma (NHL), focusing on FL.

RESULTS

Overall, 218 patients with R/R NHL, including 90 with R/R FL, received a median of eight 21-day cycles of intravenous mosunetuzumab with step-up dosing in Cycle (C) 1 (C1 Day [D] 1, 1 mg; C1D8, 2 mg; C1D15/C2D1, 60 mg; C3D1 and onwards, 30 mg). Cytokine release syndrome (CRS) was the most common adverse event (AE), occurring in 39.4% (NHL) and 44.4% (FL) of patients. Events occurred predominantly during C1 at the first loading dose; the majority were grade 1/2. CRS events were managed at the investigator's discretion with supportive care, steroids, and tocilizumab, based on protocol management guidelines. Immune effector cell-associated neurotoxicity syndrome was uncommon, reported in 0.9% (NHL) and 1.1% (FL) of patients. Neutropenia occurred in 27.5% (NHL) and 28.9% (FL) of patients (mostly grade 3/4) and could be effectively managed using granulocyte colony-stimulating factor. Tumor lysis syndrome occurred in 0.9% (NHL) and 1.1% (FL) of patients (all grade 3/4 with CRS; all resolved).

CONCLUSION

Mosunetuzumab monotherapy as treatment for R/R B-cell NHL, including FL, was associated with low rates of severe AEs (including CRS) and is suitable for outpatient administration in the community setting. Adapted protocol guidance for the management of select AEs during mosunetuzumab treatment is included.

Clinical Impact of Cytokine Release Syndrome on Prolonged Hematotoxicity after Chimeric Antigen Receptor T Cell Therapy: KyoTox A-Score, a Novel Prediction Model

Prolonged hematotoxicity is the most common long-term adverse event in chimeric antigen receptor T cell therapy (CAR-T). To evaluate the impact on prolonged cytopenia of inflammatory status after CAR T infusion, we performed a single-center retrospective study and analyzed patients with B cell lymphomas after CAR-T. Among 90 patients analyzed at 90 days after infusion, the cumulative incidence was 57.5% for prolonged neutropenia, 36.7% for anemia, and 49.8% for thrombocytopenia. Patients who experienced cytokine release syndrome (CRS) had significantly higher incidence and longer duration of prolonged cytopenia. In addition, we found that among patients with grade 1 CRS, those with a longer duration of CRS-related symptoms (>5 days; grade 1b in modified CRS grading [m-CRS]) had a significantly higher incidence and longer duration of prolonged cytopenia than those whose CRS-related symptoms resolved within 5 days (grade 1a m-CRS). Multivariate analysis revealed that a higher m-CRS grade (grade 1b or 2; hazard ratio [HR], 2.42), higher peak CRP (≥10 mg/dL; HR, 1.66), longer duration of elevated CRP (≥10 days; HR, 1.83), and a decrease in serum inorganic phosphorus concentration (≥30% from baseline; HR, 1.95) were associated with significantly higher cumulative incidence of prolonged neutropenia, as well as anemia and thrombocytopenia. Using these factors, we developed a new predictive scoring model for prolonged hematotoxicity, the KyoTox a-score, which can successfully stratify the incidence and duration of cytopenia independent of the existing model, CAR-HEMATOTOX, which is based on laboratory data at lymphodepletion. Thus, this newly developed post-CAR-T inflammation-dependent score is accurate and useful for predicting prolonged hematotoxicity.

Reduced Cytokine Release Syndrome and Improved Outcomes with Earlier Immunosuppressive Therapy in Haploidentical Stem Cell Transplantation

The optimal timing of immunosuppression and post-transplantation cyclophosphamide (PTCy) in haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is unknown. However, cytokine release syndrome (CRS) following haplo-HSCT is associated with worse transplantation outcomes, and the incidence of CRS may be affected by the timing of immunosuppression and PTCy. In this study, we compared CRS and other transplantation outcomes in 2 cohorts receiving different immunosuppression and PTCy schedules following haplo-HSCT. This was a retrospective cohort study of 91 patients who underwent haplo-HSCT at the Intermountain Health Blood and Marrow Transplant Program. The original or standard haplo-HSCT GVHD prophylaxis regimen included PTCy on days +3 and +4, with mycophenolate mofetil (MMF) and tacrolimus starting on day +5. The modified regimen adopted in November 2020 changed PTCy to days +3 and +5, with earlier introduction of tacrolimus and MMF, on day -1 and day 0, respectively. Grade ≥1 CRS occurred in 32% of patients in the modified regimen, in 82% of patients in the standard regimen (P <.0001), and 65% overall. Likewise, grade ≥2 CRS was lower with the modified regimen (16% versus 57%; P = .0002). The mean duration of CRS symptoms was longer with the standard regimen (3.14 days versus 1.44 days; P = .0003). The incidence of acute graft-versus-host disease grade III-IV or extensive chronic GVHD (cGVHD) at 1 year was lower in the modified regimen (6% versus 32%; P = .0068). No differences between the standard and modified regimens were seen in overall survival, relapse, or GVHD-free relapse-free survival (GRFS), although there appeared to be a trend toward improved GRFS with the modified regimen. Post hoc analysis comparing GRFS in patients with CRS and those without CRS found that CRS was associated with lower GRFS at 1 year (36% versus 63%; P = .0138). The duration of broad-spectrum antibiotic therapy was decreased by 7.5 days (P = .0017) and the time to hospital discharge was reduced by 7.1 days (P = .0241) with the modified regimen. This is the first analysis to evaluate and find a difference in CRS with early initiation of immunosuppressive therapy in haplo-HSCT. Our results suggest that this modified GVHD regimen benefits patients by reducing CRS and high-grade GVHD compared to the standard PTCy-based GVHD prophylaxis regimen in haplo-HSCT. Additionally, this novel regimen did not appear to negatively impact outcomes.

Multi-centers experience using therapeutic plasma exchange for corticosteroid/tocilizumab-refractory cytokine release syndrome following CAR-T therapy

The chimeric antigen receptor T (CAR-T) cell therapy significantly enhances the prognosis of various hematologic malignancies; however, the systemic expansion of CAR-T cells also gives rise to severe cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). Despite the successful application of corticosteroids and tocilizumab in alleviating severe CRS in most patients, there are still individuals who experience life-threatening CRS without responding to the aforementioned therapies. In our retrospective cohort, we conducted an analysis of clinical and laboratory parameters, including inflammatory cytokines, in 17 patients from three centers who underwent therapeutic plasma exchange (TPE) for refractory CRS with or without ICANS following CAR-T products treatment. Our findings demonstrate a significant improvement in both clinical symptoms and laboratory parameters subsequent to TPE treatment. The rapid decrease in temperature and levels of inflammatory indexes indicates the remarkable scavenging efficacy of TPE against cytokine storm following CAR-T therapy. In conclusion, TPE may serve as a valuable and safe adjunct to corticosteroids and tocilizumab in the management of severe CRS resulting from CAR-T cell infusion. We eagerly await further prospective studies to validate this finding.

Cytokine-based models for efficient differentiation between infection and cytokine release syndrome in patients with hematological malignancies

Although the efficacy of chimeric antigen receptor (CAR)-T cell therapy has been widely demonstrated, its clinical application is hampered by the complexity and fatality of its side effects. Cytokine release syndrome (CRS) is the most common toxicity following CAR-T cell infusion, and its symptoms substantially overlap with those of infection. Whereas, current diagnostic techniques for infections are time-consuming and not highly sensitive. Thus, we are aiming to develop feasible and efficient models to optimize the differential diagnosis in clinical practice. This study included 191 febrile patients from our center, including 85 with CRS-related fever and 106 with infectious fever. By leveraging the serum cytokine profile at the peak of fever, we generated differential models using a classification tree algorithm and a stepwise logistic regression analysis, respectively. The first model utilized three cytokines (IFN-β, CXCL1, and CXCL10) and demonstrated high sensitivity (90% training, 100% validation) and specificity (98.44% training, 90.48% validation) levels. The five-cytokine model (CXCL10, CCL19, IL-4, VEGF, and CCL20) also showed high sensitivity (91.67% training, 95.65% validation) and specificity (98.44% training, 100% validation). These feasible and accurate differentiation models may prompt early diagnosis of infections during immune therapy, allowing for early and appropriate intervention.

Modified EASIX scores predict severe CRS/ICANS in patients with acute myeloid leukemia following CLL1 CAR-T cell therapy

Chimeric antigen receptor T (CAR-T) cell therapy targeting CLL1 has been considered a potent weapon for patients with acute myeloid leukemia (AML). This study aims to evaluate the efficacy and toxicity of CLL1 CAR-T cell therapy in a larger cohort, with particular attention to cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Among the 32 patients assessed for efficacy, complete remission occurred in 71.88% (23/32) of cases and undetectable minimal residual disease in 14 patients. The CRS developed in all patients, with 8 individuals experiencing ICANS. Severe CRS and ICANS were observed in 11 and 2 patients, respectively. Furthermore, the Endothelial Activation and Stress Index (EASIX) and its derivatives measured before and after CLL1 CAR-T cell infusion were employed for predicting the severe complications. Significant differences were observed in EASIX scores on the day before lymphodepletion (Day BL, P = 0.023), -1 (P < 0.001), +1 (P < 0.001), and +3(P = 0.014); sEASIX scores on Day BL (P = 0.007), -1 (P < 0.001), +1 (P < 0.001), and +3 (P < 0.001); and mEASIX score on Day -1 (P = 0.004) between patients with mild and severe CRS/ICANS. Additionally, there was a significant difference in mEASIX scores between responders and non-responders on Day BL (P = 0.004) and Day -1 (P = 0.044). Our findings indicate that pre- and post-infusion assessments of EASIX/mEASIX/sEASIX scores serve as reliable prognostic indicators for severe CRS/ICANS and treatment response following CLL1 CAR-T cell therapy, which can assist physicians in implementing preemptive treatment strategies for potential severe complications and screening patients who are suitable candidates for CLL1 CAR-T cell therapy. EASIX/mEASIX/sEASIX scores serve as reliable prognostic indicators for severe CRS/ICANS following CLL1 CAR-T cell therapy. The preinfusion mEASIX scores of CLL1 CAR-T cells can effectively predict treatment response.

Immunomodulating Phytochemicals: An Insight Into Their Potential Use in Cytokine Storm Situations

Phytochemicals are compounds found in plants that possess a variety of bioactive properties, including antioxidant and immunomodulatory properties. Recent studies have highlighted the potential of phytochemicals in targeting specific signalling pathways involved in cytokine storm, a life-threatening clinical condition resulting from excessive immune cell activation and oversupply of proinflammatory cytokines. Several studies have documented the immunomodulatory effects of phytochemicals on immune function, including their ability to regulate essential cellular and molecular interactions of immune system cells. This makes them a promising alternative for cytokine storm management, especially when combined with existing chemotherapies. Furthermore, phytochemicals have been found to target multiple signalling pathways, including the TNF-α/NF-κB, IL-1/NF-κB, IFN-γ/JAK/STAT, and IL-6/JAK-STAT. These pathways play critical roles in the development and progression of cytokine storm, and targeting them with phytochemicals represents a promising strategy for controlling cytokine release and the subsequent inflammation. Studies have also investigated certain families of plant-related constituents and their potential immunomodulatory actions. In vivo and in vitro studies have reported the immunomodulatory effects of phytochemicals, which provide viable alternatives in the management of cytokine storm syndrome. The collective data from previous studies suggest that phytochemicals represent a potentially functional source of cytokine storm treatment and promote further exploration of these compounds as immunomodulatory agents for suppressing specific signalling cascade responses. Overall, the previous research findings support the use of phytochemicals as a complementary approach in managing cytokine storm and improving patient outcomes.

Taming the cytokine storm: small molecule inhibitors targeting IL-6/IL-6α receptor

Given the increasing effectiveness of immune-based therapies, management of their associated toxicities is of utmost importance. Cytokine release syndrome (CRS), characterized by elevated levels of cytokine, poses a significant challenge following the administration of antibodies and CAR-T cell therapies. CRS also contributes to multiple organ dysfunction in severe viral infections, notably in COVID-19. Given the pivotal role of IL-6 cytokine in initiating CRS, it has been considered a most potential therapeutic target to mitigate hyperactivated immune responses. While monoclonal antibodies of IL-6 show promise in mitigating cytokine storm, concerns about immunotoxicity persist, and small molecule IL-6 antagonists remain unavailable. The present study employed sophisticated computational techniques to identify potential hit compounds as IL-6 inhibitors, with the aim of inhibiting IL-6/IL-6R protein-protein interactions. Through ligand-based pharmacophore mapping and shape similarity in combination with docking-based screening, we identified nine hit compounds with diverse chemical scaffolds as potential binders of IL-6. Further, the MD simulation of 300 ns of five virtual hits in a complex with IL-6 was employed to study the dynamic behavior. To provide a more precise prediction, binding free energy was also estimated. The identified compounds persistently interacted with the residues lining the binding site of the IL-6 protein. These compounds displayed low binding energy during MMPBSA calculations, substantiating their strong association with IL-6. This study suggests promising scaffolds as potential inhibitors of IL-6/IL-6R protein-protein interactions and provides direction for lead optimization.

The critical role of endothelial cell in the toxicity associated with chimeric antigen receptor T cell therapy and intervention strategies

Chimeric antigen receptor (CAR)-T cell therapy has shown promising results in patients with hematological malignancies. However, many patients still have poor prognoses or even fatal outcomes due to the life-threatening toxicities associated with the therapy. Moreover, even after improving the known influencing factors (such as number or type of CAR-T infusion) related to CAR-T cell infusion, the results remain unsatisfactory. In recent years, it has been found that endothelial cells (ECs), which are key components of the organization, play a crucial role in various aspects of immune system activation and inflammatory response. The levels of typical markers of endothelial activation positively correlated with the severity of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxic syndrome (ICANS), suggesting that ECs are important targets for intervention and toxicity prevention. This review focuses on the critical role of ECs in CRS and ICANS and the intervention strategies adopted.

Nurses' roles in CAR-T therapy for B-cell malignancies and managing associated cytokine release syndrome

Introduction

In recent times, significant innovations have been made in cancer immunotherapy. These innovations have yielded positive outcomes, including a substantial improvement in the clinical outcomes of cancer patients, especially in the B-cell setting involving patients with B-cell malignancies.

Method

This paper explores oncology nurses' actual and expanded roles in utilizing chimeric antigen receptor T-cell (CAR-T) therapy.

Result

CAR-T therapy is an exciting innovation in cancer treatment. However, this therapy is often associated with some mild to life-threatening side effects and toxicities, including cytokine release syndrome (CRS). Unfortunately, nurses lack adequate standardized guidelines for monitoring and managing patients with CRS. This paper explains oncology nurses' actual and expanded roles in utilizing CAR-T therapy in treating B-cell malignancies based on experience and published data.

Discussion

Nurses' responsibilities for patients experiencing CAR-T toxicities with a particular focus on CRS during treatment are discussed.

Five Cases of Cytokine Release Syndrome in Patients Receiving Cytotoxic Chemotherapy Together With Nivolumab Plus Ipilimumab: A Case Report

We conducted a phase 3 clinical trial to compare the efficacy of platinum-based combination chemotherapy together with nivolumab plus ipilimumab relative to that of platinum-based combination chemotherapy together with pembrolizumab in previously untreated patients with advanced NSCLC. The trial was terminated prematurely after treatment of 295 patients because of a high proportion of treatment-related deaths, three of which were due to cytokine release syndrome (CRS), in the nivolumab plus ipilimumab treatment arm. In addition, we encountered two cases of CRS that were effectively managed, for a total of five cases (3.4%) among the 148 patients in the nivolumab plus ipilimumab arm. We here provide details of these five cases. Although patient background and timing of CRS onset differed, fever was observed before the emergence of CRS in all five cases. Oncologists should thus be aware that the development of fever during treatment of patients with nivolumab plus ipilimumab may herald the onset of CRS.

Features and outcomes of patients admitted to the ICU for chimeric antigen receptor T cell-related toxicity: a French multicentre cohort

BACKGROUND

Chimeric antigen receptor T-cell (CAR-T) therapy is increasingly used in patients with refractory haematological malignancies but can induce severe adverse events. We aimed to describe the clinical features and outcomes of patients admitted to the intensive care unit (ICU) after CAR-T therapy.

METHODS

This retrospective observational cohort study included consecutive adults admitted to either of two French ICUs in 2018-2022 within 3 months after CAR-T therapy.

RESULTS

Among 238 patients given CAR-T therapy, 84 (35.3%) required ICU admission and were included in the study, a median of 5 [0-7] days after CAR-T infusion. Median SOFA and SAPSII scores were 3 [2-6] and 39 [30-48], respectively. Criteria for cytokine release syndrome were met in 80/84 (95.2%) patients, including 18/80 (22.5%) with grade 3-4 toxicity. Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 46/84 (54.8%) patients, including 29/46 (63%) with grade 3-4 toxicity. Haemophagocytic lymphohistiocytosis was diagnosed in 15/84 (17.9%) patients. Tocilizumab was used in 73/84 (86.9%) patients, with a median of 2 [1-4] doses. Steroids were given to 55/84 (65.5%) patients, including 21/55 (38.2%) given high-dose pulse therapy. Overall, 23/84 (27.4%) patients had bacterial infections, 3/84 (3.6%) had fungal infections (1 invasive pulmonary aspergillosis and 2 Mucorales), and 2 (2.4%) had cytomegalovirus infection. Vasopressors were required in 23/84 (27.4%), invasive mechanical ventilation in 12/84 (14.3%), and dialysis in 4/84 (4.8%) patients. Four patients died in the ICU (including 2 after ICU readmission, i.e., overall mortality was 4.8% of patients). One year after CAR-T therapy, 41/84 (48.9%) patients were alive and in complete remission, 14/84 (16.7%) were alive and in relapse, and 29/84 (34.5%) had died. These outcomes were similar to those of patients never admitted to the ICU.

CONCLUSION

ICU admission is common after CAR-T therapy and is usually performed to manage specific toxicities. Our experience is encouraging, with low ICU mortality despite a high rate of grade 3-4 toxicities, and half of patients being alive and in complete remission at one year.

Severe cytokine release syndrome induced by immune checkpoint inhibitors in cancer patients - A case report and review of the literature

Cytokine release syndrome (CRS) can be induced by immune checkpoint inhibitors (ICIs). Although the incidence of CRS is low, it is often underreported. Here, we report two severe CRS cases and summarize and review 51 patients with ICI-induced CRS to explore the possible contributing factors to the disease prognosis and provide assistance for therapy. Our analysis found that the population with ICI-induced CRS consists mainly of male patients with an average age of 61.74 years. The primary malignant tumor type was lung cancer, and the clinical stage of most patients was stage IV. Notably, patients who experience a longer time to CRS onset, higher IL-6 levels, and lower platelet counts may be more likely to develop severe CRS. Cardiovascular, respiratory, neurological, and coagulation toxicities are more common in higher-grade CRS and may serve as markers for patient experiencing ICU admission, oxygen supplementation, hypotension, high-dose vasopressors usage, and intubation.

Melatonin as an immunomodulator in CD19-targeting CAR-T cell therapy: managing cytokine release syndrome

BACKGROUND

Chimeric antigen receptor CAR-T cell therapies have ushered in a new era of treatment for specific blood cancers, offering unparalleled efficacy in cases of treatment resistance or relapse. However, the emergence of cytokine release syndrome (CRS) as a side effect poses a challenge to the widespread application of CAR-T cell therapies. Melatonin, a natural hormone produced by the pineal gland known for its antioxidant and anti-inflammatory properties, has been explored for its potential immunomodulatory effects. Despite this, its specific role in mitigating CAR-T cell-induced CRS remains poorly understood.

METHODS

In this study, our aim was to investigate the potential of melatonin as an immunomodulatory agent in the context of CD19-targeting CAR-T cell therapy and its impact on associated side effects. Using a mouse model, we evaluated the effects of melatonin on CAR-T cell-induced CRS and overall survival. Additionally, we assessed whether melatonin administration had any detrimental effects on the antitumor efficacy and persistence of CD19 CAR-T cells.

RESULTS

Our findings demonstrate that melatonin effectively mitigated the severity of CAR-T cell-induced CRS in the mouse model, leading to improved overall survival outcomes. Remarkably, melatonin administration did not compromise the antitumor effectiveness or persistence of CD19 CAR-T cells, indicating its compatibility with therapeutic goals. These results suggest melatonin's potential as an immunomodulatory compound to alleviate CRS without compromising the therapeutic benefits of CAR-T cell therapy.

CONCLUSION

The study's outcomes shed light on melatonin's promise as a valuable addition to the existing treatment protocols for CAR-T cell therapies. By attenuating CAR-T cell-induced CRS while preserving the therapeutic impact of CAR-T cells, melatonin offers a potential strategy for optimizing and refining the safety and efficacy profile of CAR-T cell therapy. This research contributes to the evolving understanding of how to harness immunomodulatory agents to enhance the clinical application of innovative cancer treatments.

Value of inflammatory response and oxidative damage in the diagnosis of infections in severe alcoholic hepatitis

Severe alcoholic hepatitis is the most lethal complication in alcohol dependent patients. The concurrence of infections in these patients is very frequent. Both produce a systemic inflammatory response syndrome (SIRS), secondary to intense release of inflammatory cytokines, which can complicate the diagnosis. In our study, Interleukin (IL)-6 and IL-10 levels are higher in patients with SIRS (p<0.001 and p = 0.033, respectively). IL-4, IL-6, Interferon-gamma (IFNγ), Tumor necrosis factor alpha (TNFα) and IL-17 levels correlate with liver function, as estimated by MELD-Na (p = 0.018, p = 0.008, p = 0.009, p = 0.016 and p = 0.006, respectively). Malondialdehyde (MDA), a product of lipid peroxidation and marker of cell damage, also correlates with liver function (p = 0.002), but not with SIRS or infections. Only elevated IL-6 correlates independently with the presence of infections (RR=1.023 IC 95% 1.000-1.047), so it may be useful for the correct diagnosis in these patients. Values greater than 30 pg/mL have a sensitivity: 86.7% and specificity: 94.7% for the diagnosis of infections.

Relapsing cytokine release syndrome in a patient with metastatic renal cell carcinoma treated with pembrolizumab and axitinib therapy

As immune checkpoint inhibitors become more widely available, the optimal management of immune-related adverse events (irAEs) is becoming increasingly important. Although irAEs are diverse, reports on cytokine release syndrome are rare. Here, we report a case of a 48-year-old man with relapsing cytokine release syndrome after receiving pembrolizumab and axitinib combination therapy for metastatic renal cell carcinoma. During dose reduction of prednisolone for immune-related hepatitis on day 33 after starting pembrolizumab plus axitinib, the patient suddenly developed abdominal pain, and a few hours later became hypotensive and poorly oxygenated. Despite the use of a ventilator and high doses of catecholamines, blood pressure and oxygenation could not be maintained. Extracorporeal membrane oxygenation and intra-aortic balloon pumping were also administered. The cytokine release syndrome (CRS) was treated with tocilizumab, and his general condition improved. Lower-grade CRS relapsed four times despite a moderate dose of oral prednisolone with mycophenolate mofetil or tacrolimus. After gradual reduction in prednisolone over 5 months, the patient was discharged from the hospital. Partial remission of renal cell carcinoma continued for 21 months, and salvage radical nephrectomy was performed. The patient remained disease-free without the need for further treatment 9 months after surgery.

INSPIRED Symposium Part 3: Prevention and Management of Pediatric Chimeric Antigen Receptor T Cell-Associated Emergent Toxicities

Chimeric antigen receptor (CAR) T cell (CAR-T) therapy has emerged as a revolutionary cancer treatment modality, particularly in children and young adults with B cell malignancies. Through clinical trials and real-world experience, much has been learned about the unique toxicity profile of CAR-T therapy. The past decade brought advances in identifying risk factors for severe inflammatory toxicities, investigating preventive measures to mitigate these toxicities, and exploring novel strategies to manage refractory and newly described toxicities, infectious risks, and delayed effects, such as cytopenias. Although much progress has been made, areas needing further improvements remain. Limited guidance exists regarding initial administration of tocilizumab with or without steroids and the management of inflammatory toxicities refractory to these treatments. There has not been widespread adoption of preventive strategies to mitigate inflammation in patients at high risk of severe toxicities, particularly children. Additionally, the majority of research related to CAR-T toxicity prevention and management has focused on adult populations, with only a few pediatric-specific studies published to date. Given that children and young adults undergoing CAR-T therapy represent a unique population with different underlying disease processes, physiology, and tolerance of toxicities than adults, it is important that studies be conducted to evaluate acute, delayed, and long-term toxicities following CAR-T therapy in this younger age group. In this pediatric-focused review, we summarize key findings on CAR-T therapy-related toxicities over the past decade, highlight emergent CAR-T toxicities, and identify areas of greatest need for ongoing research.

Cytokine Release Syndrome More than Two Years after Pembrolizumab Introduction: A Case Report

A 71-year-old man with advanced lung adenocarcinoma was treated with carboplatin, pemetrexed, and pembrolizumab in June 2020. Pemetrexed and pembrolizumab maintenance therapy were continued until November 2022. A fever and severe fatigue occurred in December 2022; however, the cause of the infection was inconclusive based on the patient's symptoms, imaging findings, and culture tests. Although the patient was administered antibiotics, his general condition worsened. Considering the possible diagnosis of immune-related cytokine release syndrome (CRS), the patient was administered prednisolone (1 mg/kg/day) and showed improvement. In conclusion, CRS can occur even long after the initial administration of immune checkpoint inhibitor therapy.

[Effect of early tocilizumab intervention on patients with cytokine release syndrome following chimeric antigen receptor T cell therapy]

Objective: This study aimed to evaluate the effect of early tocilizumab intervention to relieve cytokine release syndrome (CRS) following chimeric antigen receptor T cell (CAR-T) therapy. Methods: Twenty-two patients with acute lymphoblastic leukemia who received tocilizumab to relieve CRS response after CAR-T cell infusion in our research center from October 2015 to July 2021 were retrospectively analyzed. According to the timing of tocilizumab intervention, patients were divided into the conventional and early intervention groups. Patients who received tocilizumab treatment after sustained high fever for 4 h were included in the early intervention group. The clinical data, CRS grade, and event-free survival (EFS) between the two groups were evaluated. Results: Compared with patients who used tocilizumab after severe CRS, no patients in the early intervention group died from CRS, and there was no increased risk of neurotoxicity. Eleven patients (84.62%) achieved complete remission with minimal residual lesions. The median EFS of patients in the early intervention and conventional groups was 2 (95% CI 0-5) and 7 (95% CI 3-11) months, respectively. Conclusion: Early tocilizumab intervention in patients with CRS reduces severe CRS and provides a more optimized therapeutic strategy for CRS caused by CAR-T cell therapy.

Early and Late Toxicities of Chimeric Antigen Receptor T-Cells

As chimeric antigen receptor (CAR) T-cell therapy is increasingly integrated into clinical practice across a range of malignancies, identifying and treating inflammatory toxicities will be vital to success. Early experiences with CD19-targeted CAR T-cell therapy identified cytokine release syndrome and neurotoxicity as key acute toxicities and led to unified initiatives to mitigate the influence of these complications. In this section, we provide an update on the current state of CAR T-cell-related toxicities, with an emphasis on emerging acute toxicities affecting additional organ systems and considerations for delayed toxicities and late effects.

Significance of alkaline Phosphatase After Chimeric Antigen Receptor T Cell Therapy in Multiple Myeloma

BACKGROUND

The inexpensive and readily available biomarkers for cytokine release syndrome (CRS) grading and prognosis assessment in chimeric antigen receptor (CAR)-T therapy are currently lacking. This study examined the significance of alkaline phosphatase (ALP) after CAR-T therapy in patients with relapsed/refractory multiple myeloma (MM).

METHODS

This cohort study included 27 patients with relapsed/refractory MM who were treated with CAR-T cells between December 2017 and October 2021. Patients were classified into 2 groups: normal ALP group (peak ALP <125 U/L, n = 10) and high ALP group (peak ALP ≥125 U/L, n = 17).

RESULTS

Within 1 month of CAR-T cell infusion, the incidence of ALP increases was 63%. We found that ALP levels began to rise in the second week, peaked in the third and fourth weeks, and began to decline in the second month. Moreover, the ALP levels in previous chemotherapy-responsive period were significantly lower than those after CAR-T therapy. Statistical analysis found that patients with increased ALP exhibited higher alanine aminotransferase and aspartate aminotransferase levels, higher and longer CAR-T cell proliferation, more serious CRS, higher cytokine and ferritin levels, and higher initial response rates. In addition, the duration of ALP increase was parallel to the duration of CAR-T expansion. Multivariable Cox-regression analysis showed that peak ALP was the independent predictor for progression-free survival (PFS) (HR = 0.029, 95% CI: 0.002-0.369).

CONCLUSIONS

Our results suggest that the ALP levels after CAR-T therapy could serve as a suitable biomarker for monitoring CAR-T cell proliferation, CRS grading, and prognosis in patients with MM.

Cytokine release syndrome was an independent risk factor associated with hypoalbuminemia for patients with relapsed/refractory hematological malignancies after CAR-T cell therapy

BACKGROUND & AIMS

This study aims to assess the nutritional status of patients during the different phases of the Chimeric Antigen Receptor (CAR)-T cell therapy and to identify prominent risk factors of hypoalbuminemia in patients after CAR-T treatment. The clinical consequences of malnutrition in cancer patients have been highlighted by growing evidence from previous clinical studies. Given CAR-T cell therapy's treatment intensity and possible side effects, it is important to provide patients with sufficient medical attention and support for their nutritional well-being.

METHODS

This study was conducted from May 2021 to December 2021 among patients undergoing CAR-T cell therapy at the Bone Marrow Transplantation Center in The First Affiliated Hospital of Zhejiang University School of Medicine. Logistic regression analysis was performed to investigate the risk factors associated with hypoalbuminemia. Participants were divided into the cytokine release syndrome (CRS) group (n = 60) and the non-CRS group (n = 11) to further analyze the relationship between hypoalbuminemia and CRS.

RESULTS

CRS (OR = 13.618; 95% CI = 1.499-123.709; P = 0.013) and baseline albumin (ALB) (OR = 0.854; 95% CI = 0.754-0.967; P = 0.020) were identified as the independent clinical factors associated with post-CAR-T hypoalbuminemia. According to the nadir of serum albumin, hypoalbuminemia occurred most frequently in patients with severe CRS (78.57%). The nadir of serum albumin (r =  - 0.587, P < 0.001) and serum albumin at discharge (r =  - 0.315, P = 0.01) were negatively correlated for the duration of CRS. Furthermore, patients with hypoalbuminemia deserved longer hospitalization (P = 0.04).

CONCLUSIONS

CRS was identified as a significant risk factor associated with post-CAR-T hypoalbuminemia. An obvious decline in serum albumin was observed as the grade and duration of CRS increase. However, further research is still needed to elucidate the mechanisms of CRS-associated hypoalbuminemia.

Laryngeal edema as a symptom of local cytokine release syndrome after BCMA-targeting CAR-T therapy for relapsed and refractory multiple myeloma

Cytokine release syndrome (CRS) can be a major side effect of chimeric antigen receptor T-cell (CAR-T) therapy, and may occasionally become life-threatening in patients with factors such as high tumor burden or poor performance status. Among the many CRS events observed in B-cell maturation antigen (BCMA)-targeting CAR-T therapy, local symptoms (also called local CRS) are poorly understood due to their low frequency. Here, we present the case of a 54-year-old woman with refractory multiple myeloma exhibiting laryngeal edema as a local CRS. Before CAR-T therapy, she was diagnosed with progressive disease indicated by a left thyroid mass. After local irradiation, she received the BCMA-targeting CAR-T agent idecabtagene vicleucel (ide-cel). On day 2, the patient developed CRS, which resolved on treatment with tocilizumab. However, on day 4, laryngeal edema worsened, and was judged to be a local CRS. Intravenous dexamethasone rapidly reduced this edema. In conclusion, laryngeal edema rarely occurs as a local CRS, and to the best of our knowledge, has never been reported after ide-cel infusion. Dexamethasone was effective for reducing the local reaction that persisted after treatment of systemic symptoms with tocilizumab.

Update on Immunotherapy Cardiotoxicity: Checkpoint Inhibitors, CAR T, and Beyond

OPINION STATEMENT

Immunotherapy is an innovative approach to cancer treatment that involves using the body's immune system to fight cancer. The landscape of immunotherapy is constantly evolving, as new therapies are developed and refined. Some of the most promising approaches in immunotherapy include immune checkpoint inhibitors (ICIs): these drugs target proteins on the surface of T-cells that inhibit their ability to attack cancer cells. By blocking these proteins, checkpoint inhibitors allow T-cells to recognize and destroy cancer cells more effectively. CAR T-cell therapy: this therapy involves genetically modifying a patient's own T-cells to recognize and attack cancer cells. CAR T-cell therapy exhibits favorable response in many patients with refractory hematological cancers with growing clinical trials in solid tumors. Immune system modulators: these drugs enhance the immune system's ability to fight cancer by stimulating the production of immune cells or inhibiting the activity of immune-suppressing cells. While immunotherapy has shown great promise in the treatment of cancer, it can also pose significant cardiac side effects. Some immunotherapy drugs like ICIs can cause myocarditis, which can lead to chest pain, shortness of breath, and heart failure. Other cardiac side effects of ICIs include arrhythmias, pericarditis, vasculitis, and accelerated atherosclerosis. It is important for patients receiving immunotherapy to be monitored closely for these side effects, as prompt treatment can help prevent serious complications. Patients should also report any symptoms to their healthcare providers right away, so that appropriate action can be taken. CAR T-cell therapy can also illicit an exaggerated immune response creating cytokine release syndrome (CRS) that may precipitate cardiovascular events: arrhythmias, myocardial infarction, and heart failure. Overall, while immune modulating therapy is a promising and expanding approach to cancer treatment, it is important to weigh the potential benefits against the risks and side effects, especially in patients with high risk for cardiovascular complications.

Complete spectrum of adverse events associated with chimeric antigen receptor (CAR)-T cell therapies

Chimeric antigen receptor (CAR)-T cell therapies have been approved by FDA to treat relapsed or refractory hematological malignancies. However, the adverse effects of CAR-T cell therapies are complex and can be challenging to diagnose and treat. In this review, we summarize the major adverse events, including cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), and CAR T-cell associated HLH (carHLH), and discuss their pathophysiology, symptoms, grading, and diagnosis systems, as well as management. In a future outlook, we also provide an overview of measures and modifications to CAR-T cells that are currently being explored to limit toxicity.

Cytokine release syndrome after bronchoalveolar lavage

BACKGROUND

Immunosuppressed bone marrow transplant patients with pulmonary infiltrates routinely undergo bronchoscopy with bronchoalveolar lavage (BAL) to investigate potential etiologies. Cytokine release syndrome after BAL is unreported in the literature in general and in this patient population.

CASE PRESENTATION

We report on an allogeneic bone marrow transplant patient with non-infectious organizing pneumonia of the lungs who developed delayed and rapidly progressive shock and hypoxia post-procedure over the course of 12 h resulting in intensive care unit admission for supportive care. BAL was characterized by a marked lymphocytic, cytotoxic T cell infiltrate on pathology and flow cytometry without clear evidence of infection. The patient's clinical status improved quickly only after the initiation of high dose intravenous steroids and returned to baseline as an outpatient.

CONCLUSION

The patient's clinical data and course suggest a cytotoxic T cell response from the lung and BAL as the etiology. With an increasing number of cellular therapies for cancer entering the clinic, the potential for unusual but morbid complications from routine bronchoscopy should be considered.

Preliminary assessment of cardiotoxicity in chimeric antigen receptor T cell therapy: a systematic review and meta-analysis

As a novel anticancer therapy, chimeric antigen receptor T (CAR T) cell therapy may lead to cardiotoxic reactions. However, the exact incidence remains unclear. Our study aimed to preliminarily assess the prevalence of cardiotoxicity after CAR T cell treatment using a systematic review and meta-analysis. PubMed, Embase, Web of Science, and Cochrane databases were searched for potentially relevant studies. All types of relevant clinical studies were screened and assessed for risk bias. In most instances, random-effect models were used for data analysis, and heterogeneity between studies was evaluated. Standard quality assessment tools were used to assess quality. The study was registered with PROSPERO (CRD42022304611). Eight eligible studies comprising 3567 patients, including seven observational studies and one controlled study, were identified. The incidence of cardiovascular events was 16.7% [95% confidence interval (CI) 0.138-0.200, P < 0.01)]. Arrhythmia was the most common disorder, with an incidence of 6.5% (95% CI 0.029-0.115, P < 0.01). The occurrence of cardiotoxicity was associated with cytokine release syndrome (CRS), with a prevalence of 18.7% (95% CI 0.107-0.315, P < 0.01). Moreover, such adverse reactions were more common when CRS > 2 (OR = 0.07, 95% CI 0.02-0.29, P < 0.01). The risk of cardiotoxicity was not notably higher in patients receiving CAR T cell therapy than in those receiving traditional anticancer treatment. However, sufficient attention should be paid to this. And further evidence from large-scale clinical trials are needed.

CAR-T cell therapy: Where are we now, and where are we heading?

Chimeric antigen receptor (CAR)-T-cell therapies have exhibited remarkable efficacy in the treatment of hematologic malignancies, with 9 CAR-T-cell products currently available. Furthermore, CAR-T cells have shown promising potential for expanding their therapeutic applications to diverse areas, including solid tumors, myocardial fibrosis, and autoimmune and infectious diseases. Despite these advancements, significant challenges pertaining to treatment-related toxic reactions and relapses persist. Consequently, current research efforts are focused on addressing these issues to enhance the safety and efficacy of CAR-T cells and reduce the relapse rate. This article provides a comprehensive overview of the present state of CAR-T-cell therapies, including their achievements, existing challenges, and potential future developments.

[Síndrome hemofagocítico linfohistiocitario secundario a Dengue en una paciente de 6 años: reporte de caso]

Background

Dengue fever is a mosquito-borne infectious disease endemic in over 100 countries around the world. Among the complications that dengue can cause the Hemophagocytic Lymphohistiocytosis is one of great concern for its severity and complex diagnosis.

Case report

Hereby we document a case of this disease expressed on a previously healthy 6-year-old female patient whose dengue infection was so severe that needed intensive care management with vasoactive drugs and diuretics. After a short period of wellness began newly with fever, pancytopenia, hepatitis, and inflammatory response symptoms.

Conclusions

A Dengue associated Hemophagocytic Lymphohistiocytosis syndrome was suspected and treated with intravenous corticosteroids on a 3-day scheme at no signs of malignancy with excellent response. The health care professionals must know about this not novel entity in order to reach an efficient diagnosis and treatment mostly, but not only, those in tropical and sub-tropical regions of the word were dengue virus is endemic.

Practical guidelines for the management of adverse events of the T cell engager bispecific tebentafusp

Tebentafusp is a new T cell receptor bispecific fusion protein and the first approved treatment option for human leucocyte antigen-A*02:01 (HLA-A*02:01) metastatic uveal melanoma, with a proven benefit in overall survival versus the investigator's choice. As a first-in-class therapeutic option, this Immune mobilising monoclonal T cell receptor Against Cancer (ImmTAC) is associated with a new adverse event (AE) profile. Based on clinical experience, a national expert group discussed recommendations for tebentafusp treatment, focusing on AE management. Further topics included prerequisites for initiating tebentafusp treatment, appropriate treatment setting, and patient selection criteria. To provide guidance for treating physicians, the resulting recommendations are summarised including a model standard operating procedure for AE management. Patients in good clinical condition and with a low tumour burden are good candidates for tebentafusp treatment, particularly if treated as early as possible after the diagnosis of metastatic disease. The safety profile of tebentafusp is manageable and includes two major pathologies: cytokine release syndrome (CRS) and skin-related events. Postdose monitoring should thus focus on pyrexia and hypotension as the first symptoms of cytokine release. To minimise the risk of hypotension associated with CRS, patients should receive intravenous fluids before starting treatment. The monitoring of liver values is crucial, as patients may experience an increase in transaminases, which can even manifest as tumour lysis syndrome.

Tocilizumab for Cytokine Release Syndrome Management After Haploidentical Hematopoietic Cell Transplantation With Post-Transplantation Cyclophosphamide-Based Graft-Versus-Host Disease Prophylaxis

Cytokine release syndrome (CRS) is a common complication after haploidentical hematopoietic cell transplantation (HaploHCT). Severe CRS after haploHCT leads to higher risk of non-relapse mortality (NRM) and worse overall survival (OS). Tocilizumab (TOCI) is an interleukin-6 receptor inhibitor and is commonly used as first-line for CRS management after chimeric antigen receptor T cell therapy, but the impact of TOCI administration for CRS management on Haplo HCT outcomes is not known. In this single center retrospective analysis, we compared HCT outcomes in patients treated with or without TOCI for CRS management after HaploHCT with post-transplantation cyclophosphamide- (PTCy-) based graft-versus-host disease (GvHD) prophylaxis. Of the 115 patients eligible patients who underwent HaploHCT at City of Hope between 2019 to 2021 and developed CRS, we identified 11 patients who received tocilizumab for CRS management (TOCI). These patients were matched with 21 patients who developed CRS but did not receive tocilizumab (NO-TOCI) based on age at the time of HCT (≤64 years or >65 years or older), conditioning intensity (myeloablative versus reduced-intensity/nonmyeloablative), and CRS grading (1, 2, versus 3-4). Instead of 22 controls, we chose 21 patients because there was only 1 control matched with 1 TOCI treatment patient in 1 stratum. With only 11 patients in receiving tocilizumab for CRS treatment, matching with 21 patients who developed CRS but did not receive tocilizumab, we had 80% power to detect big differences (hazard ratio [HR] = 3.4 or higher) in transplantation outcomes using a 2-sided 0.05 test. The power would be reduced to about 20% to 30% if the difference was moderate (HR = 2.0) using the same test. No CRS-related deaths were recorded in either group. Median time to neutrophil engraftment was 21 days (range 16-43) in TOCI and 18 days (range 14-23) in NO-TOCI group (HR = 0.55; 95% confidence interval [CI] = 0.28-1.06, P = .08). Median time to platelet engraftment was 34 days (range 20-81) in TOCI and 28 days (range 12-94) in NO-TOCI group (HR = 0.56; 95% CI = 0.25-1.22, P = .19). Cumulative incidences of day 100 acute GvHD grades II-IV (P = .97) and grades III-IV (P = .47) were similar between the 2 groups. However, cumulative incidence of chronic GvHD at 1 year was significantly higher in patients receiving TOCI (64% versus 24%; P = .05). Rates of NRM (P = .66), relapse (P = .83), disease-free survival (P = .86), and overall survival (P = .73) were similar at 1 year after HCT between the 2 groups. Tocilizumab administration for CRS management after HaploHCT appears to be safe with no short-term adverse effect and no effect on relapse rate. However, the significantly higher cumulative incidence of chronic GvHD, negates the high efficacy of PTCy on GvHD prophylaxis in this patient population. Therefore using tocilizumab for CRS management in the HaploHCT population with PTCy maybe kept only for patients with severe CRS. The impact on such approach on long term outcome in HaploHCT with PTCy will need to be evaluated in a larger retrospective study or a prospective manner.

Harnessing the potential of CAR-T cell therapy: progress, challenges, and future directions in hematological and solid tumor treatments

Traditional cancer treatments use nonspecific drugs and monoclonal antibodies to target tumor cells. Chimeric antigen receptor (CAR)-T cell therapy, however, leverages the immune system's T-cells to recognize and attack tumor cells. T-cells are isolated from patients and modified to target tumor-associated antigens. CAR-T therapy has achieved FDA approval for treating blood cancers like B-cell acute lymphoblastic leukemia, large B-cell lymphoma, and multiple myeloma by targeting CD-19 and B-cell maturation antigens. Bi-specific chimeric antigen receptors may contribute to mitigating tumor antigen escape, but their efficacy could be limited in cases where certain tumor cells do not express the targeted antigens. Despite success in blood cancers, CAR-T technology faces challenges in solid tumors, including lack of reliable tumor-associated antigens, hypoxic cores, immunosuppressive tumor environments, enhanced reactive oxygen species, and decreased T-cell infiltration. To overcome these challenges, current research aims to identify reliable tumor-associated antigens and develop cost-effective, tumor microenvironment-specific CAR-T cells. This review covers the evolution of CAR-T therapy against various tumors, including hematological and solid tumors, highlights challenges faced by CAR-T cell therapy, and suggests strategies to overcome these obstacles, such as utilizing single-cell RNA sequencing and artificial intelligence to optimize clinical-grade CAR-T cells.

Treatment of cytokine release syndrome-induced vascular endothelial injury using mesenchymal stem cells

Cytokine release syndrome (CRS) is an acute systemic inflammatory reaction in which hyperactivated immune cells suddenly release a large amount of cytokines, leading to exaggerated inflammatory responses, multiple organ dysfunction, and even death. Although palliative treatment strategies have significantly reduced the overall mortality, novel targeted treatment regimens with superior therapy efficacy are urgently needed. Vascular endothelial cells (ECs) are important target cells of systemic inflammation, and their destruction is considered to be the initiating event underlying many serious complications of CRS. Mesenchymal stem/stromal cells (MSCs) are multipotent cells with self-renewing differentiation capacity and immunomodulatory properties. MSC transplantation can effectively suppress the activation of immune cells, reduce the bulk release of cytokines, and repair damaged tissues and organs. Here, we review the molecular mechanisms underlying CRS-induced vascular endothelial injury and discuss potential treatments using MSCs. Preclinical studies demonstrate that MSC therapy can effectively repair endothelium damage and thus reduce the incidence and severity of ensuing CRS-induced complications. This review highlights the therapeutic role of MSCs in fighting against CRS-induced EC damage, and summarizes the possible therapeutic formulations of MSCs for improved efficacy in future clinical trials.

Allogenic mesenchymal stromal cells and their extracellular vesicles in COVID-19 induced ARDS: a randomized controlled trial

BACKGROUND AND AIMS

The main causes of death in patients with severe Coronavirus disease-2019 (COVID-19) are acute respiratory distress syndrome (ARDS) and multiorgan failure caused by a severe inflammatory cascade. Novel treatment strategies, such as stem-cell-based therapy and their derivatives can be used to relieve inflammation in these cases. In this study, we aimed to evaluate the safety and efficacy of therapy using mesenchymal stromal cells (MSCs) and their derived extracellular vesicles in COVID-19 patients.

MATERIALS AND METHODS

COVID-19 patients with ARDS were included in this study and allocated into two study and control groups using block randomization. While all patients received recommended treatment based on guidelines from the national advisory committee for COVID-19 pandemic, the two intervention groups received two consecutive injections of MSCs (100 × 10⁶ cells) or one dose of MSCs (100 × 10⁶ cells) followed by one dose of MSC-derived extracellular vesicles (EVs). Patients were assessed for safety and efficacy by evaluating clinical symptoms, laboratory parameters, and inflammatory markers at baseline and 48 h after the second intervention.

RESULTS

A total number of 43 patients (the MSC alone group = 11, MSC plus EV group = 8, and control group = 24) were included in the final analysis. Mortality was reported in three patients in the MSC alone group (RR: 0.49; 95% CI 0.14-1.11; P = 0.08); zero patient in the MSC plus EV group (RR: 0.08; 95% CI 0.005-1.26; P = 0.07) and eight patients in the control group. MSC infusion was associated with a decrease in inflammatory cytokines such as IL-6 (P = 0.015), TNF-α (P = 0.034), IFN-γ (P = 0.024), and CRP (P = 0.041).

CONCLUSION

MSCs and their extracellular vesicles can significantly reduce the serum levels of inflammatory markers in COVID-19 patients, with no serious adverse events. Trial registration IRCT, IRCT registration number: IRCT20200217046526N2. Registered 13th April 2020, http://www.irct.ir/trial/47073 .

Infections occurring following IL6 blockade for the management of cytokine release syndrome in onco-hematology patients

BACKGROUND

Cytokine release syndrome (CRS) is a common adverse event of CAR T cell or bispecific antibody (bsAb) therapy. Anti-IL6/IL6R drugs are used in the management of auto-immune diseases. Some reports showed increased risk of bacterial infection in this context. In onco-hematology, there are few data about the occurrence of infection after administration of an anti-IL6/IL6R for CRS.

METHODS

We retrospectively reviewed all consecutive patients treated in Gustave Roussy Cancer Campus between 2018 and 2021, who received anti-IL6/IL6R for CRS due to bsAb in phase I clinical trials or adoptive cellular therapy (ACT). We constituted a control group including all the patients treated in the same clinical trials or standard of care ACT, naïve of anti-IL6/IL6R.

RESULTS

Fifty-two patients have been included. In the anti-IL6/IL6R group (n = 26), five patients developed a grade 2 to 5 infection within a month after anti-IL6/IL6R treatment, including two grade 5 infections. In the control group (n = 26), only one patient had a grade 3 infection. The two patients who had grade 5 infections were treated for diffuse large B cell lymphoma (DLBCL), one with bsAb and the other with CAR T cell. Fifty percent (3/6) of DLBCL patients who received an anti-IL6/IL6R presented an infection, one of which was a grade 5. In solid tumor patients treated with bsAb and anti-IL6/IL6R, only one patient (/9, 11%) developed a grade 2 viral infection.

CONCLUSION

It seems that the use of anti-IL6/IL6R in CRS secondary to bsAb administration in solid tumors patients does not significantly increase the risk of infection, as opposed to DLBCL patients where secondary infection might be a concern.

Recovery-model: A model for CAR T-cell-related thrombocytopenia in relapsed/refractory multiple myeloma

BACKGROUND

Patients with multiple myeloma (MM) treated with anti-B cell maturation antigen (BCMA) and chimeric antigen receptor (CAR) T-cell therapy tend to show delayed platelet recovery.

PATIENTS AND METHODS

This single-center retrospective observational study included a cohort of patients with MM treated with anti-BCMA CAR-T cells in ChiCTR-OPC-16009113, ChiCTR1800018137, and ChiCTR1900021153.

RESULTS

Fifty-eight patients with MM treated with anti-BCMA CAR-T cells were included. Delayed platelet recovery (platelet count not recovering to 50 × 10⁹/L within 28 days) was observed in 36 % of patients. Regression analysis identified several factors that influenced platelet recovery, and accordingly, a Recovery-Model was developed. A high Recovery-Model score indicates a greater risk of delayed platelet recovery after CAR-T cell infusion and reflects the risk of hematologic toxicity. The model's predictive biomarkers included baseline platelet count, baseline hemoglobin level, logarithm of baseline Ferritin level, and cytokine release syndrome grade. Finally, survival analysis showed a significant relationship between overall survival, delayed platelet recovery (p = 0.0457), and a high Recovery-Model score (p = 0.0011).

CONCLUSIONS

Inflammation-related factors and bone marrow reserves are associated with delayed platelet recovery. Therefore, we developed a model to predict the risk of delayed platelet recovery and hematological toxicity in relapsed/refractory patients with MM after anti-BCMA CAR-T cell treatment.

CAR t-cell therapy in BOlogNa-NEUrotoxicity TReatment and Assessment in Lymphoma (CARBON-NEUTRAL): proposed protocol and results from an Italian study

OBJECTIVE

To investigate neurotoxicity clinical and instrumental features, incidence, risk factors, and early and long-term prognosis in lymphoma patients who received CAR T-cell therapy.

METHODS

In this prospective study, consecutive refractory B-cell non-Hodgkin lymphoma patients who received CAR T-cell therapy were included. Patients were comprehensively evaluated (neurological examination, EEG, brain MRI, and neuropsychological test) before and after (two and twelve months) CAR T-cells. From the day of CAR T-cells infusion, patients underwent daily neurological examinations to monitor the development of neurotoxicity.

RESULTS

Forty-six patients were included in the study. The median age was 56.5 years, and 13 (28%) were females. Seventeen patients (37%) developed neurotoxicity, characterized by encephalopathy frequently associated with language disturbances (65%) and frontal lobe dysfunction (65%). EEG and brain FDG-PET findings also supported a predominant frontal lobe involvement. The median time at onset and duration were five and eight days, respectively. Baseline EEG abnormalities predicted ICANS development in the multivariable analysis (OR 4.771; CI 1.081-21.048; p = 0.039). Notably, CRS was invariably present before or concomitant with neurotoxicity, and all patients who exhibited severe CRS (grade ≥ 3) developed neurotoxicity. Serum inflammatory markers were significantly higher in patients who developed neurotoxicity. A complete neurological resolution following corticosteroids and anti-cytokines monoclonal antibodies was reached in all patients treated, except for one patient developing a fatal fulminant cerebral edema. All surviving patients completed the 1-year follow-up, and no long-term neurotoxicity was observed.

CONCLUSIONS

In the first prospective Italian real-life study, we presented novel clinical and investigative insights into ICANS diagnosis, predictive factors, and prognosis.

RNA silencing of GM-CSF in CAR-T cells reduces the secretion of multiple inflammatory cytokines

Chimeric antigen receptor T (CAR-T) cell therapy has become a research hotspot in the field of hematological malignancies. However, CAR-T cell therapy can lead to immunotherapy-associated side effects including cytokine release syndrome and neurotoxicity. Gene depletion of GM-CSF in CAR-T cells was found preventive against adverse effects, but additional transfections were required to produce CAR-T cells. In this study, we interrupted GM-CSF expression in CAR-T cells by inserting the GM-CSF shRNA-expression cassette in the CAR vector. Reduction of GM-CSF in CAR-T cells could decrease the level of several proinflammatory cytokines without hampering the killing capacity. The manufacture of GM-CSF knockdown CAR-T cells does not require complicated transfections, which makes it more practical and feasible for clinical application.

Impact of Preemptive Use of Tocilizumab on Chimeric Antigen Receptor T Cell Outcomes in Non-Hodgkin Lymphoma

Despite the impressive results of chimeric antigen receptor (CAR) T cell treatment for lymphomas, adverse events such as cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), and infections are major issues that can lead to intensive care unit (ICU) admission and death. Current guidelines recommend tocilizumab for treating patients with CRS grade (G) ≥2; however, the optimal timing of intervention has yet to be determined. Our institution adopted the preemptive use of tocilizumab in cases of persistent G1 CRS, defined as fever (≥38 °C) for >24 hours. This preemptive tocilizumab treatment aimed to reduce evolution to severe (G≥3) CRS, ICU admission, or death. We report on 48 prospectively collected consecutive patients with non-Hodgkin lymphoma treated with autologous CD19-targeted CAR T cells. In total, 39 patients (81%) developed CRS. CRS started as G1 in 28 patients, as G2 in patients, and as G3 in 1 patient. Tocilizumab was administered in 34 patients, including 23 patients who received "preemptive" tocilizumab and 11 patients who received tocilizumab for G2 or G3 CRS from the onset of symptoms. CRS resolved without worsening severity in 19 patients out of 23 (83%) who received preemptive tocilizumab; 4 patients (17%) progressed from G1 to G2 for the development of hypotension and quickly responded to the introduction of steroids. No patients treated with a preemptive approach developed G3 or G4 CRS. Ten out of 48 patients (21%) were diagnosed with ICANS, including 5 patients with G3 or G4. Six infectious events occurred. The overall ICU admission rate was 19%. ICANS management was the most relevant reason for ICU admission (7 patients), and no patient required ICU to manage CRS. No deaths from CAR-T toxicity were observed. Our data indicate that preemptive tocilizumab use is feasible and useful in reducing severe CRS and CRS-related ICU admission, with no impact on neurotoxicity or infection rate. Therefore, early use of tocilizumab can be considered, especially for patients at high risk of CRS.

Management of adverse events in young adults and children with acute B-cell lymphoblastic leukemia receiving anti-CD19 chimeric antigen receptor (CAR) T-cell therapy

With impressive clinical advancements in immune effector cell therapies targeting CD19, chimeric antigen receptor (CAR) T-cell therapy has emerged as a new paradigm for treating relapsed/refractory B-cell malignancies. Currently, three second-generation CAR T-cell therapies have been approved, of which only tisagenlecleucel (tisa-cel) is approved for treating children and young adults with B-cell acute lymphoblastic leukemia (ALL) with durable remission rates of approximately 60-90%. Although CAR T-cell therapies are considered to treat refractory B-ALL, they are associated with unique toxicities such as cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). The severity of CAR T-cell therapy toxicities can vary according to several clinical factors. In rare cases, severe CRS can progress to a fulminant hyperinflammatory syndrome known as hemophagocytic lymphohistiocytosis, which has a poor prognosis. The first-line treatments for CRS/ICANS include tocilizumab and corticosteroids. When severe CAR T-cell toxicity is resistant to first-line treatment, an additional approach is required to manage the persistent inflammation. In addition to CRS/ICANS, CAR T-cell therapy can cause early and delayed hematological toxicity, which can predispose patients to severe infections. The use of growth factors and anti-infective prophylaxis should follow institutional guidelines according to patient-specific risk factors. This review provides a thorough summary of updated practical recommendations for managing acute and delayed adverse effects following anti-CD19 CAR T-cell therapy in adults and children.

Apoptosis of Hematopoietic Stem Cells Contributes to Bone Marrow Suppression Following Chimeric Antigen Receptor T Cell Therapy

Chimeric antigen receptor (CAR) T cell (CAR-T) therapy represents a revolutionary treatment for patients with relapsed/refractory hematologic malignancies. However, its use can result in significant toxicities, including cytokine release syndrome (CRS), a potentially life-threatening clinical syndrome resulting from the release of proinflammatory cytokines upon T cell activation. In addition, patients who develop CRS often experience prolonged cytopenias, and those with the most severe CRS also have the longest delays in full marrow recovery. Although an association between CRS and delayed bone marrow recovery has been established, the precise mechanism underlying this phenomenon remains unknown. This study was conducted to test our hypothesis that delayed bone marrow recovery following CAR-T therapy is caused by elevation of proinflammatory cytokines, leading to apoptosis and depletion of hematopoietic stem and progenitor cells (HSPCs). SCID-beige mice bearing intraperitoneal CD19+ Raji cell tumors were treated with injection of human CD19.28z CAR T cells. Bone marrow was then harvested for analysis by flow cytometry, and HSPCs were isolated for whole-transcriptome analysis by RNA sequencing. Complete blood counts and serum cytokine levels were measured as well. A second model was developed in which SCID-beige mice were treated with murine IFN-γ (mIFN-γ), murine IL-6 (mIL-6), or both. Bone marrow was harvested, and flow cytometry assays were conducted to evaluate the degree of apoptosis and proliferation on specific HSPC populations. SCID-beige mice bearing intraperitoneal Raji cell tumors that were treated with CAR-T therapy developed CRS, with elevations of several proinflammatory cytokines, including profound elevation of human IFN-γ. Gene set enrichment analysis of RNA sequencing data revealed that genes associated with apoptosis were significantly upregulated in HSPCs from mice that developed CRS. Endothelial protein C receptor (EPCR)-negative HSCs, a subset of HSCs that is poised for terminal differentiation, was found to be specifically decreased in mice that were treated with CAR T cells. Furthermore, HSPCs were found to have increased levels of apoptosis upon treatment with mIFN-γ and mIL-6, whereas short-term HSCs and multipotent progenitors exhibited increases in proliferation with mIFN-γ treatment alone. The results from this study provide evidence that the elevation of proinflammatory cytokines following CAR-T therapy impacts the bone marrow through a combined mechanism: pluripotent HSCs that are exposed to elevated levels of IFN-γ and IL-6 undergo increased cell death, while more committed progenitor cells become more proliferative in response to elevated IFN-γ. These combined effects lead to depleted stores of repopulating HSCs and ultimately cytopenias. © 2023 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Explorations of CRISPR/Cas9 for improving the long-term efficacy of universal CAR-T cells in tumor immunotherapy

Chimeric antigen receptor (CAR) T therapy has shown remarkable success in discovering novel CAR-T cell products for treating malignancies. Despite of successful results from clinical trials, CAR-T cell therapy is ineffective for long-term disease progression. Numerous challenges of CAR-T cell immunotherapy such as cell dysfunction, cytokine-related toxicities, TGF-β resistance, GvHD risks, antigen escape, restricted trafficking, and tumor cell infiltration still exist that hamper the safety and efficacy of CAR-T cells for malignancies. The accumulated data revealed that these challenges could be overcome with the advanced CRISPR genome editing technology, which is the most promising tool to knockout TRAC and HLA genes, inhibiting the effects of dominant negative receptors (PD-1, TGF-β, and B2M), lowering the risks of cytokine release syndrome (CRS), and regulating CAR-T cell function in the tumor microenvironment (TME). CRISPR technology employs DSB-free genome editing methods that robustly allow efficient and controllable genetic modification. The present review explored the innovative aspects of CRISPR/Cas9 technology for developing next-generation/universal allogeneic CAR-T cells. The present manuscript addressed the ongoing status of clinical trials of CRISPR/Cas9-engineered CAR-T cells against cancer and pointed out the off-target effects associated with CRISPR/Cas9 genome editing. It is concluded that CAR-T cells modified by CRISPR/Cas9 significantly improved antitumor efficacy in a cost-effective manner that provides opportunities for novel cancer immunotherapies.

Chimeric antigen receptor T cells therapy in solid tumors

Chimeric antigen receptor T cells therapy (CAR-T therapy) is a class of ACT therapy. Chimeric antigen receptor (CAR) is an engineered synthetic receptor of CAR-T, which give T cells the ability to recognize tumor antigens in a human leukocyte antigen-independent (HLA-independent) manner and enables them to recognize more extensive target antigens than natural T cell surface receptor (TCR), resulting in tumor destruction. CAR-T is composed of an extracellular single-chain variable fragment (scFv) of antibody, which serves as the targeting moiety, hinge region, transmembrane spacer, and intracellular signaling domain(s). CAR-T has been developing in many generations, which differ according to costimulatory domains. CAR-T therapy has several limitations that reduce its wide availability in immunotherapy which we can summarize in antigen escape that shows either partial or complete loss of target antigen expression, so multiplexing CAR-T cells are promoted to enhance targeting of tumor profiles. In addition, the large diversity in the tumor microenvironment also plays a major role in limiting this kind of treatment. Therefore, engineered CAR-T cells can evoke immunostimulatory signals that rebalance the tumor microenvironment. Using CAR-T therapy in treating the solid tumor is mainly restricted by the difficulty of CAR-T cells infiltrating the tumor site, so local administration was developed to improve the quality of treatment. The most severe toxicity after CAR-T therapy is on-target/on-tumor toxicity, such as cytokine release syndrome (CRS). Another type of toxicity is on-target/off-tumor toxicity which originates from the binding of CAR-T cells to target antigen that has shared expression on normal cells leading to damage in healthy cells and organs. Toxicity management should become a focus of implementation to permit management beyond specialized centers.

Phase 1 Study of Safety and Preliminary Clinical Activity of JNJ-63898081, a PSMA and CD3 Bispecific Antibody, for Metastatic Castration-Resistant Prostate Cancer

INTRODUCTION

Cancer immunotherapies have limited efficacy in prostate cancer due to the immunosuppressive prostate microenvironment. Prostate specific membrane antigen (PSMA) expression is prevalent in prostate cancer, preserved during malignant transformation, and increases in response to anti-androgen therapies, making it a commonly targeted tumor associated antigen for prostate cancer. JNJ-63898081 (JNJ-081) is a bispecific antibody targeting PSMA-expressing tumor cells and CD3-expressing T cells, aiming to overcome immunosuppression and promoting antitumor activity.

PATIENTS AND METHODS

We conducted a phase 1 dose escalation study of JNJ-081 in patients with metastatic castration-resistance prostate cancer (mCRPC). Eligible patients included those receiving ≥1 prior line treatment with either novel androgen receptor targeted therapy or taxane for mCRPC. Safety, pharmacokinetics, and pharmacodynamics of JNJ-081, and preliminary antitumor response to treatment were evaluated. JNJ-081 was administered initially by intravenous (IV) then by subcutaneous (SC) route.

RESULTS

Thirty-nine patients in 10 dosing cohorts received JNJ-081 ranging from 0.3 µg/kg to 3.0 µg/kg IV and 3.0 µg/kg to 60 µg/kg SC (with step-up priming used at higher SC doses). All 39 patients experienced ≥1 treatment-emergent AE, and no treatment-related deaths were reported. Dose-limiting toxicities were observed in 4 patients. Cytokine release syndrome (CRS) was observed at higher doses with JNJ-081 IV or SC; however, CRS and infusion-related reaction (IRR) were reduced with SC dosing and step-up priming at higher doses. Treatment doses >30 µg/kg SC led to transient PSA decreases. No radiographic responses were observed. Anti-drug antibody responses were observed in 19 patients receiving JNJ-081 IV or SC.

CONCLUSION

JNJ-081 dosing led to transient declines in PSA in patients with mCRPC. CRS and IRR could be partially mitigated by SC dosing, step-up priming, and a combination of both strategies. T cell redirection for prostate cancer is feasible and PSMA is a potential therapeutic target for T cell redirection in prostate cancer.

Cytokine profiles are associated with prolonged hematologic toxicities after B-cell maturation antigen targeted chimeric antigen receptor-T-cell therapy

BACKGROUND AIMS

The considerable efficacy of B-cell maturation antigen-targeted chimeric antigen receptor (CAR)-T-cell therapy has been extensively demonstrated in the treatment of relapsed or refractory multiple myeloma. Nevertheless, in clinical practice, prolonged hematologic toxicity (PHT) extends hospital stay and impairs long-term survival.

METHODS

This retrospective study reviewed 99 patients with relapsed or refractory multiple myeloma who underwent B-cell maturation antigen CAR-T-cell therapy at our institution between April 2018 and September 2021 (ChiCTR1800017404).

RESULTS

Among 93 evaluable patients, the incidence of prolonged hematologic toxicities was high after CAR-T-cell infusion, including 38.71% (36/93) of patients with prolonged neutropenia, 22.58% (21/93) with prolonged anemia and 59.14% (55/93) with prolonged thrombocytopenia. In addition, 9.68% (9/93) of patients experienced prolonged pancytopenia. Our multivariate analyses identified that cytokine profiles were independent risk factors for PHTs, whereas a sufficient baseline hematopoietic function and high CD4/CD8 ratio of CAR-T cells were protective factors for PHTs after CAR-T-cell infusion. Subgroup analyses found that the kinetics of post-CAR-T hematologic parameters were primarily determined by the collective effects of cytokine release syndrome and baseline hematopoietic functions, and showed influential weights for the three lineages.

CONCLUSIONS

Our findings improve the understanding of the impact of cytokines on hematopoietic functions, which could contribute to the mechanism investigation and exploration of potential intervention strategies.

[Cellular kinetics and outcome of tisagenlecleucel for diffuse large B-cell lymphoma]

CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown promise as treatment of relapsed or refractory B-cell malignancies. However, the clinical utility of early CAR-T monitoring within 1 month after infusion has not been elucidated. In this study, we quantitatively measured CAR-T kinetics in peripheral blood on days 2, 4, 7, 9, 11, 14, 21, and 28 post-infusion using flow cytometry and quantitative polymerase chain reaction in 13 patients with relapsed refractory diffuse large B-cell lymphoma (DLBCL) treated with tisagenlecleucel (tisa-cel). No relationships were identified between bulk CAR-T kinetics and treatment outcomes. Interestingly, the magnitude of CD4⁺ CAR-T expansion was higher in responders than in nonresponders, while CD8⁺ CAR-T expansion was minimal in responders. Additionally, CAR-T proliferation was more pronounced in patients with cytokine release syndrome. Our results suggest that CD4⁺ CAR-T cellular kinetics within 1 month after CAR-T infusion may predict its efficacy after tisa-cel therapy in adult patients with DLBCL.