Tisagenlecleucel in adult relapsed or refractory follicular lymphoma: the phase 2 ELARA trial

Approved CAR-T therapies have reproducible efficacy and safety in clinical practice

CAR-T cell therapy has established itself as a highly effective treatment for hematological malignancies. There are currently six commercial CAR-T products that have been FDA approved for diseases such as B-ALL, LBCL, MCL, FL, MM, and CLL/SLL. "Real-world" studies allow us to evaluate outcomes from the general population to determine their efficacy and safety compared to those who were included in the original trials. Based on several well conducted "Real-world" studies that represent diverse populations, we report that outcomes from the original trials that led to the approval of these therapies are comparable to those in practice.

Outpatient administration of CAR T-cell therapies using a strategy of no remote monitoring and early CRS intervention

ABSTRACT

Recent studies demonstrating the feasibility of outpatient chimeric antigen receptor (CAR)-modified T-cell therapy administration are either restricted to CARs with 41BB costimulatory domains or use intensive at-home monitoring. We report outcomes of outpatient administration of all commercially available CD19- and B-cell maturation antigen (BCMA)-directed CAR T-cell therapy using a strategy of no remote at-home monitoring and an early cytokine release syndrome (CRS) intervention strategy. Patients with hematologic malignancies who received CAR T-cell therapy in the outpatient setting during 2022 to 2023 were included. Patients were seen daily in the cancer center day hospital for the first 7 to 10 days and then twice weekly through day 30. The primary end point was to determine 3-, 7-, and 30-day post-CAR T-cell infusion hospitalizations. Early CRS intervention involved administering tocilizumab as an outpatient for grade ≥1 CRS. Fifty-eight patients received outpatient CAR T-cell infusion (33 myeloma, 24 lymphoma, and 1 acute lymphoblastic leukemia). Of these, 17 (41%), 16 (38%), and 9 patients (21%) were admitted between days 0 to 3, 4 to 7, and 8 to 30 after CAR T-cell infusion, respectively. The most common reason for admission was CAR T-cell-related toxicities (33/42). Hospitalization was prevented in 15 of 35 patients who received tocilizumab for CRS as an outpatient. The nonrelapse mortality rates were 1.7% at 1 month and 3.4% at 6 months. In conclusion, we demonstrate that the administration of commercial CAR T-cell therapies in an outpatient setting is safe and feasible without intensive remote monitoring using an early CRS intervention strategy.

Safety and efficacy of odronextamab in patients with relapsed or refractory follicular lymphoma

BACKGROUND

Odronextamab, a CD20×CD3 bispecific antibody that engages cytotoxic T cells to destroy malignant B cells, has demonstrated encouraging activity across multiple subtypes of relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma.

PATIENTS AND METHODS

This phase II study (ELM-2; NCT03888105) evaluated odronextamab in patients with R/R follicular lymphoma (FL) after ≥2 lines of systemic therapy. Patients received intravenous odronextamab in 21-day cycles, with step-up dosing in Cycle 1 to help mitigate the risk of cytokine release syndrome (CRS), until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by independent central review.

RESULTS

Among 128 patients evaluated, 95% completed Cycle 1, and 85% completed ≥4 cycles. At 20.1 months' efficacy follow-up, ORR was 80.0% and complete response rate was 73.4%. Median duration of complete response was 25.1 months. Median progression-free survival was 20.7 months, and median overall survival was not reached. Discontinuation of odronextamab due to adverse events (AEs) occurred in 16% of patients. The most common treatment-emergent AEs were CRS (56%; grade ≥3 1.7% [1/60] with 0.7/4/20 mg step-up), neutropenia (39%), and pyrexia (38%).

CONCLUSIONS

Odronextamab achieved high complete response rates with generally manageable safety in patients with heavily pretreated R/R FL.

Bispecific antibodies and autologous chimeric antigen receptor T cell therapies for treatment of hematological malignancies

In recent years, the therapeutic landscape for hematological malignancies has markedly advanced, particularly since the inaugural approval of autologous chimeric antigen receptor T cell (CAR-T) therapy in 2017 for relapsed/refractory acute lymphoblastic leukemia (ALL). Autologous CAR-T therapy involves the genetic modification of a patient's T cells to specifically identify and attack cancer cells, while bispecific antibodies (BsAbs) function by binding to both cancer cells and immune cells simultaneously, thereby triggering an immune response against the tumor. The subsequent approval of various CAR-T therapies and BsAbs have revolutionized the treatment of multiple hematological malignancies, highlighting high response rates and a subset of patients achieving prolonged disease control. This review explores the mechanisms underlying autologous CAR-T therapies and BsAbs, focusing on their clinical application in multiple myeloma, ALL, and non-Hodgkin lymphoma. We provide comprehensive insights into their individual efficacy, limitations concerning broad application, and the potential of combination therapies. These upcoming strategies aim to propel the field forward, paving the way for safer and more effective therapeutic interventions in hematological malignancies.

PostFocus: automated selective post-acquisition high-throughput focus restoration using diffusion model for label-free time-lapse microscopy

MOTIVATION

High-throughput time-lapse imaging is a fundamental tool for efficient living cell profiling at single-cell resolution. Label-free phase-contrast video microscopy enables noninvasive, nontoxic, and long-term imaging. The tradeoff between speed and throughput, however, implies that despite the state-of-the-art autofocusing algorithms, out-of-focus cells are unavoidable due to the migratory nature of immune cells (velocities >10 μm/min). Here, we propose PostFocus to (i) identify out-of-focus images within time-lapse sequences with a classifier, and (ii) deploy a de-noising diffusion probabilistic model to yield reliable in-focus images.

RESULTS

De-noising diffusion probabilistic model outperformed deep discriminative models with a superior performance on the whole image and around cell boundaries. In addition, PostFocus improves the accuracy of image analysis (cell and contact detection) and the yield of usable videos.

AVAILABILITY AND IMPLEMENTATION

Open-source code and sample data are available at: https://github.com/kwu14victor/PostFocus.

Finding Your CAR: The Road Ahead for Engineered T Cells

Adoptive cellular therapy using chimeric antigen receptors (CARs) has transformed immunotherapy by engineering T cells to target specific antigens on tumor cells. As the field continues to advance, pathology laboratories will play increasingly essential roles in the complicated multi-step process of CAR T-cell therapy. These include detection of targetable tumor antigens by flow cytometry or immunohistochemistry at the time of disease diagnosis and the isolation and infusion of CAR T cells. Additional roles include: i) detecting antigen loss or heterogeneity that renders resistance to CAR T cells as well as identifying alternative targetable antigens on tumor cells, ii) monitoring the phenotype, persistence, and tumor infiltration properties of CAR T cells and the tumor microenvironment for factors that predict CAR T-cell therapy success, and iii) evaluating side effects and biomarkers of CAR T-cell cytotoxicity such as cytokine release syndrome. This review highlights existing technologies that are applicable to monitoring CAR T-cell persistence, target antigen identification, and loss. Also discussed are emerging technologies that address new challenges such as how to put a brake on CAR T cells. Although pathology laboratories have already provided companion diagnostic tests important in immunotherapy (eg, programmed death-ligand 1, microsatellite instability, and human epidermal growth factor receptor 2 testing), it draws attention to the exciting new translational research opportunities in adoptive cellular therapy.

Nanomaterials Boost CAR-T Therapy for Solid Tumors

T cell engineering, particularly via chimeric antigen receptor (CAR) modifications for enhancing tumor specificity, has shown efficacy in treating hematologic malignancies. The extension of CAR-T cell therapy to solid tumors, however, is impeded by several challenges: The absence of tumor-specific antigens, antigen heterogeneity, a complex immunosuppressive tumor microenvironment, and physical barriers to cell infiltration. Additionally, limitations in CAR-T cell manufacturing capacity and the high costs associated with these therapies restrict their widespread application. The integration of nanomaterials into CAR-T cell production and application offers a promising avenue to mitigate these challenges. Utilizing nanomaterials in the production of CAR-T cells can decrease product variability and lower production expenses, positively impacting the targeting and persistence of CAR-T cells in treatment and minimizing adverse effects. This review comprehensively evaluates the use of various nanomaterials in the production of CAR-T cells, genetic modification, and in vivo delivery. It discusses their underlying mechanisms and potential for clinical application, with a focus on improving specificity and safety in CAR-T cell therapy.

Lisocabtagene maraleucel in follicular lymphoma: the phase 2 TRANSCEND FL study

An unmet need exists for patients with relapsed/refractory (R/R) follicular lymphoma (FL) and high-risk disease features, such as progression of disease within 24 months (POD24) from first-line immunochemotherapy or disease refractory to both CD20-targeting agent and alkylator (double refractory), due to no established standard of care and poor outcomes. Chimeric antigen receptor (CAR) T cell therapy is an option in R/R FL after two or more lines of prior systemic therapy, but there is no consensus on its optimal timing in the disease course of FL, and there are no data in second-line (2L) treatment of patients with high-risk features. Lisocabtagene maraleucel (liso-cel) is an autologous, CD19-directed, 4-1BB CAR T cell product. The phase 2 TRANSCEND FL study evaluated liso-cel in patients with R/R FL, including 2L patients who all had POD24 from diagnosis after treatment with anti-CD20 antibody and alkylator ≤6 months of FL diagnosis and/or met modified Groupe d'Etude des Lymphomes Folliculaires criteria. Primary/key secondary endpoints were independent review committee-assessed overall response rate (ORR)/complete response (CR) rate. At data cutoff, 130 patients had received liso-cel (median follow-up, 18.9 months). Primary/key secondary endpoints were met. In third-line or later FL (n = 101), ORR was 97% (95% confidence interval (CI): 91.6‒99.4), and CR rate was 94% (95% CI: 87.5‒97.8). In 2L FL (n = 23), ORR was 96% (95% CI: 78.1‒99.9); all responders achieved CR. Cytokine release syndrome occurred in 58% of patients (grade ≥3, 1%); neurological events occurred in 15% of patients (grade ≥3, 2%). Liso-cel demonstrated efficacy and safety in patients with R/R FL, including high-risk 2L FL. ClinicalTrials.gov identifier: NCT04245839 .

Safety and activity of lenalidomide in combination with obinutuzumab in patients with relapsed indolent non-Hodgkin lymphoma: a single group, open-label, phase 1/2 trial

Background

Rituximab and lenalidomide is a preferred option for relapsed indolent B cell non-Hodgkin lymphoma. Obinutuzumab may be a superior combination partner with lenalidomide given enhanced antibody dependent cellular cytotoxicity and phagocytosis compared to rituximab. Our aim was to determine the recommended phase 2 dose, safety, and activity of lenalidomide in combination with fixed dose of obinutuzumab in relapsed and refractory indolent B cell non-Hodgkin lymphoma.

Methods

In this single-arm, open-label, phase 1/2 trial, we enrolled patients with relapsed or refractory WHO Grade 1-3A follicular lymphoma, marginal zone lymphoma and small lymphocytic lymphoma and adequate performance status (ECOG 0-2) at the MD Anderson Cancer Center. We excluded patients with evidence of ongoing transformation to aggressive lymphoma. During phase 1, 1000 mg intravenous obinutuzumab was administered with three predefined levels of oral lenalidomide in a 3 + 3 dose escalation design to establish lenalidomide 20 mg as the recommended phase 2 dose. During phase 2, patients received induction therapy with six 28-day cycles of lenalidomide 20 mg with intravenous obinutuzumab 1000 mg. In accordance with our prior experience with lenalidomide plus rituximab, patients who were responding to the combination could receive up to 6 additional cycles (up to 12 cycles in total) of combination therapy. Dosing of obinutuzumab was continued in all responding patients after cycle 6 every 2 months for a total of 30 months from the start of therapy. The decision of number of cycles of combination therapy beyond 6 was at discretion of the investigator and was included to allow individualisation of therapy to maximise response while minimising exposure. The co-primary objectives were to evaluate the safety and overall response, defined as the proportion of patients who achieved a complete or partial response in relapsed and refractory indolent non-Hodgkin lymphoma at the end of induction therapy, according to Cheson and colleagues (2007 criteria). The secondary endpoints were complete response after induction therapy and time to event endpoints including time to progression, progression free survival, and overall survival. Analyses were intent to treat in the efficacy cohort and per-treated in the safety population in all patients who received at least one dose of either investigational agent. This trial is registered with ClinicalTrials.gov, NCT01995669.

Findings

Between June 03, 2014, and 07 March 2019, we completed planned enrolment, and 66 patients started therapy including 9 patients in phase 1 and 57 patients in phase 2. All patients were evaluated for safety and the 60 patients treated at the recommended phase 2 dose of lenalidomide 20 mg were evaluable for activity. Grade 3-4 haematological toxicities included neutropenia 21% (14/66) and thrombocytopenia 11% (7/66) with no cases of febrile neutropenia. Grade 3-4 non-haematological toxicities included lung infection 8% (5/66), fatigue 8% (5/66) and rash 6% (4/66). By Cheson 2007 criteria, 90% (54/60, 95% CI: 79-96) achieved an overall response at the end of induction meeting the prespecified activity endpoint. Complete responses were seen in 33% (20/60, 95% CI: 22-47) at the end of induction. Median progression free survival, time to progression and overall survival have not been reached after median follow-up of 41.7 months. Estimated 4-year progression free survival rates were 55% (95% CI: 42-73), time to progression of 56% (95% CI: 43-74) and overall survival of 84% (95% CI: 74-95).

Interpretation

Our findings suggest that oral lenalidomide with obinutuzumab is safe and highly active in patients with relapsed and refractory indolent B cell non-Hodgkin lymphoma and is associated with prolonged remission duration. The study is limited by the lack of a control arm leading to cross-trial comparisons to evaluate activity. Future randomised trials comparing this regime to rituximab and lenalidomide are warranted.

Funding

Genentech and an MD Anderson Core grant.

Epcoritamab monotherapy in patients with relapsed or refractory follicular lymphoma (EPCORE NHL-1): a phase 2 cohort of a single-arm, multicentre study

BACKGROUND

A standard of care and optimal duration of therapy have not been established for patients with multiply relapsed or refractory follicular lymphoma. The aim of this study was to evaluate epcoritamab, a novel CD3 × CD20 bispecific antibody, in the third-line and later setting of follicular lymphoma.

METHODS

EPCORE NHL-1 is a multicohort, single-arm, phase 1-2 trial conducted at 88 sites across 15 countries. Here, we report the primary analysis of patients with relapsed or refractory follicular lymphoma in the phase 2 part of the trial, which included the pivotal (dose expansion) cohort and the cycle 1 optimisation cohort. Eligible patients were aged 18 years or older, had relapsed or refractory CD20+ follicular lymphoma (grade 1-3A), an Eastern Cooperative Oncology Group performance status of up to 2, and had received at least two previous lines of therapy (including an anti-CD20 monoclonal antibody and an alkylating agent or lenalidomide). Patients were treated with subcutaneous epcoritamab 48 mg in 28-day cycles: weekly in cycles 1-3, biweekly in cycles 4-9, and every 4 weeks until disease progression or unacceptable toxicity. To mitigate the risk and severity of cytokine release syndrome, in the pivotal cohort, cycle 1 consisted of a step-up dosing regimen of a 0·16-mg priming dose on day 1 and a 0·80-mg intermediate dose on day 8, followed by subsequent 48-mg full doses and prophylactic prednisolone 100 mg; in the cycle 1 optimisation cohort, a second intermediate dose of 3 mg on day 15, adequate hydration, and prophylactic dexamethasone 15 mg were evaluated during cycle 1 to further reduce risk and severity of cytokine release syndrome. Primary endpoints were independently reviewed overall response rate for the pivotal cohort and the proportion of patients with grade 2 or worse and any-grade cytokine release syndrome for the cycle 1 optimisation cohort. Analyses were done in all enrolled patients who had received at least one dose of epcoritamab. This study is registered with ClinicalTrials.gov, NCT03625037, and is ongoing.

FINDINGS

Between June 19, 2020, and April 21, 2023, 128 patients (median age 65 years [IQR 55-72]; 49 [38%] female and 79 [62%] male) were enrolled and treated in the pivotal cohort (median follow-up 17·4 months [IQR 9·1-20·9]). The overall response rate was 82·0% (105 of 128 patients; 95% CI 74·3-88·3), with a complete response rate of 62·5% (80 of 128; 95% CI 53·5-70·9). The most common grade 3-4 treatment-emergent adverse event was neutropenia in 32 (25%) of 128 patients. Grade 1-2 cytokine release syndrome was reported in 83 (65%) of 128 patients; grade 3 cytokine release syndrome was reported in two (2%). Immune effector cell-associated neurotoxicity syndrome was reported in eight (6%) of 128 patients (five [4%] grade 1; three [2%] grade 2). Between Oct 25, 2022, and Jan 8, 2024, 86 patients (median age 64 years [55-71]; 37 [43%] female and 49 [57%] male) were enrolled and treated in the cycle 1 optimisation cohort. The incidence of cytokine release syndrome was 49% (42 of 86 patients; eight [9%] grade 2; none of grade 3 or worse), with no reported immune effector cell-associated neurotoxicity syndrome.

INTERPRETATION

Epcoritamab monotherapy showed clinically meaningful activity in patients with multiply relapsed or refractory follicular lymphoma, and had a manageable safety profile.

FUNDING

Genmab and AbbVie.

Quality of Life Evaluation in Patients with Follicular Cell Lymphoma: A Real-World Study in Europe and the United States

INTRODUCTION

Follicular lymphoma (FL) is an indolent subtype of non-Hodgkin's lymphoma (NHL), characterized by a long natural course of remissions/relapses. We aimed to evaluate real-world quality of life (QoL) in patients with FL, by line of therapy (LOT), and across countries.

METHODS

Data were drawn from the Adelphi FL Disease Specific Programme™, a cross-sectional survey of physicians and their patients in Europe [France, Germany, Italy, Spain, the United Kingdom (UK)], and the United States (US) from June 2021 to January 2022. Patients provided demographics and patient-reported outcomes via the European Organisation for Research and Treatment of Cancer QoL questionnaire (EORTC QLQ-C30). Bivariate analysis assessed QoL versus NHL, across LOT [first line (1L), second line (2L), third line or later (3L+)] and country.

RESULTS

Patients (n = 401) had a mean [standard deviation (SD)] age of 66.0 (9.24) years, 58.1% were male, and 41.9%/22.9% were Ann Arbor stage III/IV. Patients with FL mean EORTC global health status (GHS)/QoL, nausea/vomiting, pain, dyspnea, appetite loss, and diarrhea scores were statistically significantly worse (p < 0.05) versus the NHL reference values. Mean (SD) GHS/QoL worsened from 1L [56.5 (22.21)] to 3L+ [50.4 (20.11)]. Physical and role functioning, fatigue, pain, dyspnea, and diarrhea scores also significantly worsened across later LOTs (p < 0.05). Across all functional domains, mean scores were significantly lower (p < 0.05) and almost all symptom scores (excluding diarrhea) were significantly higher (p < 0.05) for European versus US patients.

CONCLUSIONS

Patients with FL at later LOTs had significantly worse scores in most QoL aspects than earlier LOTs. European patients had significantly lower functioning and higher symptom burden than in the US. These real-world findings highlight the need for novel FL therapies that alleviate patient burden, positively impacting QoL.

Diagnosis, management and follow-up of follicular lymphoma: a consensus practice statement from the Australasian Lymphoma Alliance

Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma subtype, accounting for 15-20% of all lymphoma diagnoses. Although typically slow-growing and responsive to frontline therapies, advanced-stage FL remains incurable with current treatments and typically follows a chronic relapsing/remitting course with increasingly shorter responses to subsequent lines of therapy. Outcomes are highly variable; some patients experience prolonged first remissions that may approximate a 'functional cure'. By contrast, a significant minority of patients experience disease progression shortly after frontline treatment resulting in high rates of lymphoma-related mortality. Reflecting on the heterogeneous natural history of FL, clinical practice varies widely, particularly in controversial areas, including appropriate disease staging, selection of management strategies and duration of clinical follow-up. This position statement presents an evidence-based synthesis of the literature for application in Australasian practice.

Infusion and delivery strategies to maximize the efficacy of CAR-T cell immunotherapy for cancers

Chimeric antigen receptor (CAR) T-cell therapy has achieved substantial clinical outcomes for tumors, especially for hematological malignancies. However, extending the duration of remission, reduction of relapse for hematological malignancies and improvement of the anti-tumor efficacy for solid tumors are challenges for CAR-T cells immunotherapy. Besides the endeavors to enhance the functionality of CAR-T cell per se, optimization of the infusion and delivery strategies facilitates the breakthrough of the hurdles that limited the efficacy of this cancer immunotherapy. Here, we summarized the infusion and delivery strategies of CAR-T cell therapies under pre-clinical study, clinical trials and on-market status, through which the improvements of safety and efficacy for hematological and solid tumors were analyzed. Of note, novel infusion and delivery strategies, including local-regional infusion, biomaterials bearing the CAR-T cells and multiple infusion technique, overcome many limitations of CAR-T cell therapy. This review provides hints to determine infusion and delivery strategies of CAR-T cell cancer immunotherapy to maximize clinical benefits.

Fueling CARs: metabolic strategies to enhance CAR T-cell therapy

CAR T cells are widely applied for relapsed hematological cancer patients. With six approved cell therapies, for Multiple Myeloma and other B-cell malignancies, new insights emerge. Profound evidence shows that patients who fail CAR T-cell therapy have, aside from antigen escape, a more glycolytic and weakened metabolism in their CAR T cells, accompanied by a short lifespan. Recent advances show that CAR T cells can be metabolically engineered towards oxidative phosphorylation, which increases their longevity via epigenetic and phenotypical changes. In this review we elucidate various strategies to rewire their metabolism, including the design of the CAR construct, co-stimulus choice, genetic modifications of metabolic genes, and pharmacological interventions. We discuss their potential to enhance CAR T-cell functioning and persistence through memory imprinting, thereby improving outcomes. Furthermore, we link the pharmacological treatments with their anti-cancer properties in hematological malignancies to ultimately suggest novel combination strategies.

Subsequent Malignancies After CD19-Targeted Chimeric Antigen Receptor T Cells in Patients With Lymphoma

Chimeric antigen receptor (CAR) T cells are an established treatment for B cell non-Hodgkin lymphomas (B-NHL). With the remarkable success in improving survival, understanding the late effects of CAR T cell therapy is becoming more relevant. The aim of this study is to determine the incidence of subsequent malignancies in adult patients with B-NHL. We retrospectively studied 355 patients from 2 different medical centers treated with four different CAR T cell products from 2016 to 2022. The overall cumulative incidence for subsequent malignancies at 36 months was 14% (95% CI: 9.2%, 19%). Subsequent malignancies were grouped into 3 primary categories: solid tumor, hematologic malignancy, and dermatologic malignancy with cumulative incidences at 36 months of 6.1% (95% CI: 3.1%-10%), 4.5% (95% CI: 2.1%-8.1%) and 4.2% (95% CI: 2.1%-7.5%) respectively. Notably, no cases of T cell malignancies were observed. In univariable analysis, increasing age was associated with higher risk for subsequent malignancy. While the overall benefits of CAR T products continue to outweigh their potential risks, more studies and longer follow ups are needed to further demonstrate the risks, patterns, and molecular pathways that lead to the development of subsequent malignancies.

License for a CAR T: Examining patient eligibility

Chimeric antigen receptor (CAR) T-cell therapy has transformed the treatment landscape of lymphoma and is now approved by the FDA for multiple indications. Given that the indications for CAR T-cell therapy are expanding, a larger patient population will be eligible to receive this treatment in the coming years. Pivotal clinical trials leading to FDA approval of CAR T-cell products required patients to have adequate organ function and good performance status. In the real world, however, the patient population eligible for CAR T-cell therapy includes patients who are older, frail, have poor performance status, and have multiple comorbidities. Studies have shown that CAR T-cell therapy is relatively safe and tolerable in such frail patients, however, there is no agreed upon consensus or guidelines to assess eligibility for CAR T-cell therapy at this moment. Gaining further insight into such patient populations will be vital in order to safely provide and expand access to CAR T-cell therapy.

Clinical Practice Recommendations for Hematopoietic Cell Transplantation and Cellular Therapies in Follicular Lymphoma: A Collaborative Effort on Behalf of the American Society for Transplantation and Cellular Therapy and the European Society for Blood and Marrow Transplantation

Follicular lymphoma (FL) is the most common indolent B-cell non-Hodgkin lymphoma (NHL), accounting for nearly one-third of all NHL. The therapeutic landscape for patients with FL has significantly expanded over the past decade, but the disease continues to be considered incurable. Hematopoietic cell transplantation (HCT) is potentially curative in some cases. Recently, the emergence of chimeric antigen receptor T-cell therapy (CAR-T) for patients with relapsed/refractory (R/R) FL has yielded impressive response rates and long-term remissions, but definitive statement on the curative potential of CAR-T is currently not possible due to limited patient numbers and relatively short follow up. A consensus on the contemporary role, optimal timing, and sequencing of HCT (autologous or allogeneic) and cellular therapies in FL is needed. As a result, the American Society of Transplantation and Cellular Therapy (ASTCT) Committee on Practice Guidelines endorsed this effort to formulate consensus recommendations to address this unmet need. The RAND-modified Delphi method was used to generate 15 consensus statements/recommendations. These clinical practice recommendations will help guide clinicians managing patients with FL. Of note, the use of bispecific antibodies in R/R FL was not in the scope of this project.

Current understanding and management of CAR T cell-associated toxicities

Chimeric antigen receptor (CAR) T cell therapy has revolutionized the treatment of several haematological malignancies and is being investigated in patients with various solid tumours. Characteristic CAR T cell-associated toxicities such as cytokine-release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) are now well-recognized, and improved supportive care and management with immunosuppressive agents has made CAR T cell therapy safer and more feasible than it was when the first regulatory approvals of such treatments were granted in 2017. The increasing clinical experience with these therapies has also improved recognition of previously less well-defined toxicities, including movement disorders, immune effector cell-associated haematotoxicity (ICAHT) and immune effector cell-associated haemophagocytic lymphohistiocytosis-like syndrome (IEC-HS), as well as the substantial risk of infection in patients with persistent CAR T cell-induced B cell aplasia and hypogammaglobulinaemia. A more diverse selection of immunosuppressive and supportive-care pharmacotherapies is now being utilized for toxicity management, yet no universal algorithm for their application exists. As CAR T cell products targeting new antigens are developed, additional toxicities involving damage to non-malignant tissues expressing the target antigen are a potential hurdle. Continued prospective evaluation of toxicity management strategies and the design of less-toxic CAR T cell products are both crucial for ongoing success in this field. In this Review, we discuss the evolving understanding and clinical management of CAR T cell-associated toxicities.

Overcoming the challenges of primary resistance and relapse after CAR-T cell therapy

INTRODUCTION

While CAR T-cell therapy has led to remarkable responses in relapsed B-cell hematologic malignancies, only 50% of patients ultimately have a complete, sustained response. Understanding the mechanisms of resistance and relapse after CAR T-cell therapy is crucial to future development and improving outcomes.

AREAS COVERED

We review reasons for both primary resistance and relapse after CAR T-cell therapies. Reasons for primary failure include CAR T-cell manufacturing problems, suboptimal fitness of autologous T-cells themselves, and intrinsic features of the underlying cancer and tumor microenvironment. Relapse after initial response to CAR T-cell therapy may be antigen-positive, due to CAR T-cell exhaustion or limited persistence, or antigen-negative, due to antigen-modulation on the target cells. Finally, we discuss ongoing efforts to overcome resistance to CAR T-cell therapy with enhanced CAR constructs, manufacturing methods, alternate cell types, combinatorial strategies, and optimization of both pre-infusion conditioning regimens and post-infusion consolidative strategies.

EXPERT OPINION

There is a continued need for novel approaches to CAR T-cell therapy for both hematologic and solid malignancies to obtain sustained remissions. Opportunities for improvement include development of new targets, optimally combining existing CAR T-cell therapies, and defining the role for adjunctive immune modulators and stem cell transplant in enhancing long-term survival.

Long-term Remissions Following CD20-Directed Chimeric Antigen Receptor-Adoptive T-cell Therapy

Chimeric antigen receptor (CAR) T-cell therapy produces high response rates in refractory B-cell non-Hodgkin lymphoma, but long-term data are minimal to date. In this study, we present long-term follow-up of a pilot trial testing a CD20-targeting third-generation CAR in patients with relapsed B-cell lymphomas following cyclophosphamide-only lymphodepletion. Two of the three patients in the trial, with mantle cell lymphoma and follicular lymphoma, had remissions lasting more than 7 years, though they ultimately relapsed. The absence of B-cell aplasia in both patients suggested a lack of functional CAR T-cell persistence, leading to the hypothesis that endogenous immune responses were responsible for these long-term remissions. Correlative immunologic analyses supported this hypothesis, with evidence of new humoral and cellular antitumor immune responses proximal to clinical response time points. Collectively, our results suggest that CAR T-cell therapy may facilitate epitope spreading and endogenous immune response formation in lymphomas. Significance: Two of three patients treated with CD20-targeted CAR T-cell therapy had long-term remissions, with evidence of endogenous antitumor immune response formation. Further investigation is warranted to develop conditions that promote epitope spreading in lymphomas.

Polatuzumab vedotin, venetoclax, and an anti-CD20 monoclonal antibody in relapsed/refractory B-cell non-Hodgkin lymphoma

The Phase 2 portion of this study evaluated safety and efficacy of polatuzumab vedotin 1.8 mg/kg and venetoclax 800 mg, plus fixed-dose obinutuzumab 1000 mg or rituximab 375 mg/m2 in patients with relapsed/refractory (R/R) follicular lymphoma (FL) or diffuse large B-cell lymphoma (DLBCL), respectively. Patients with complete response (CR) or partial response (PR)/stable disease (FL) or CR/PR (DLBCL) at end of induction (EOI; six 21-day cycles) received post-induction therapy with venetoclax and obinutuzumab or rituximab, respectively. Primary endpoint was CR rate at EOI. Safety-evaluable populations included 74 patients (FL cohort; median age 64 years; progression of disease within 24 months on first-line treatment, 25.7%; FL International Prognostic Index 3-5, 54.1%; ≥2 previous therapies, 74.3%) and 57 patients (DLBCL cohort; median age 65 years; International Prognostic Index 3-5, 54.4%; ≥2 previous therapies, 77.2%). The most common non-hematologic adverse events (mostly Grades 1-2) in the FL and DLBCL cohorts were diarrhea (55.4% and 47.4%, respectively) and nausea (47.3% and 36.8%); neutropenia was the most common Grades 3-4 toxicity (39.2% and 52.6%). Efficacy-evaluable populations included patients treated at the recommended Phase 2 dose (FL, n = 49; DLBCL, n = 48). CR rates at EOI were 59.2% (FL) and 31.3% (DLBCL); median progression-free survival was 22.8 months (95% confidence interval [CI], 14.5-not evaluable) and 4.6 months (95% CI, 3.6-8.1), respectively. Polatuzumab vedotin plus venetoclax and obinutuzumab/rituximab had acceptable safety in patients with R/R FL or DLBCL, with promising response rates in R/R FL, including high-risk patients.

Efficacy and safety of MIL62, a novel glycoengineered type Ⅱ anti-CD20 monoclonal antibody, combined with lenalidomide in patients with relapsed/refractory follicular lymphoma or marginal zone lymphoma: a multicentre, single-arm, phase 1b/2 trial

Background

MIL62, a novel glycoengineered type Ⅱ anti-CD20 monoclonal antibody, with a nearly completely afucosylated N-glycans in Fc region, has demonstrated superior activity compared with rituximab and obinutuzumab in vitro and in vivo, respectively.

Methods

This multicentre, single-arm, phase 1b/2 trial aimed to explore the efficacy, pharmacokinetics, and safety of MIL62 combined with lenalidomide in patients with relapsed/refractory (R/R) follicular lymphoma (FL) or marginal zone lymphoma (MZL). Eligible patients included those who had histopathologically confirmed CD20 positive FL (grade 1-3a) or MZL and failed to be treated with rituximab. Patients received intravenously infused MIL62 1000 mg (cycle 1: day 1, 15; cycles 2-8: day 1, cycles 10 and 12: day 1) combined with oral lenalidomide (once a day, days 2-22, the initial dose was 10 mg, and the maximum dose was 20 mg) for 12 cycles, 28 days as a cycle. The primary endpoint was objective response rate (ORR) assessed by investigator per Lugano 2014 criteria every 3 cycles. This study was registered in ClinicalTrials.gov (NCT04110301).

Findings

Between November 22, 2019 and December 22, 2020, 54 patients were enrolled from 11 hospitals in China and received study treatment. Fifty patients were included in the efficacy analysis set, and 43 patients (86%, 95% CI: 73, 94) achieved objective response, meeting the pre-specified primary endpoint. Disease control rate was 96% (48/50, 95% CI: 86, 100), proportion of patients with duration of response (DoR) > 6 months was 77% (33/43). The median follow-up for survival was 12.3 months (IQR 12.0-12.6). The 1-year progression-free survival rate was 72% (95% CI: 57, 83), 9-month DoR rate was 74% (95% CI: 58, 85), and 1-year overall survival rate was 98% (95% CI: 85, 100). Most common TRAEs were neutropenia (93%, 50/54), leukopenia (85% 46/54), thrombocytopenia (61% 33/54), lymphopenia (32% 17/54), and alanine aminotransferase increased (20% 11/54).

Interpretation

MIL62 combined with lenalidomide showed promising efficacy in patients with R/R FL and MZL. A multicentre, randomized, open-label, phase Ⅲ trial of MIL62 combined with lenalidomide versus lenalidomide in anti-CD20 monoclonal antibody refractory FL patients is ongoing (NCT04834024).

Funding

Beijing Mabworks Biotech Co. Ltd, Beijing China and the National Science and Technology Major Project for Key New Drug Development (2017ZX09304015).

Moving T-Cell Therapies into the Standard of Care for Patients with Relapsed or Refractory Follicular Lymphoma: A Review

Patients with follicular lymphoma, an indolent form of non-Hodgkin lymphoma, typically experience multiple relapses over their disease course. Periods of remission become progressively shorter with worse clinical outcomes after each subsequent line of therapy. Currently, no clear standard of care/preferred treatment approach exists for patients with relapsed or refractory follicular lymphoma. As novel agents continue to emerge for treatment in the third-line setting, guidance is needed for selecting the most appropriate therapy for each patient. Several classes of targeted therapeutic agents, including monoclonal antibodies, phosphoinositide 3-kinase inhibitors, enhancer of zeste homolog 2 inhibitors, chimeric antigen receptor (CAR) T-cell therapies, and bispecific antibodies, have been approved by regulatory authorities based on clinical benefit in patients with relapsed or refractory follicular lymphoma. Additionally, antibody-drug conjugates and other immunocellular therapies are being evaluated in this setting. Effective integration of CAR-T cell therapy into the treatment paradigm after two or more prior therapies requires appropriate patient selection based on transformation status following a rebiopsy; a risk evaluation based on age, fitness, and remission length; and eligibility for CAR-T cell therapy. Consideration of important logistical factors (e.g., proximity to the treatment center and caregiver support during key periods of CAR-T cell therapy) is also critical. Overall, an individualized treatment plan that considers patient-related factors (e.g., age, disease status, tumor burden, comorbidities) and prior treatment types is recommended for patients with relapsed or refractory follicular lymphoma. Future analyses of real-world data and a better understanding of mechanisms of relapse are needed to further refine patient selection and identify optimal sequencing of therapies in this setting.

Translational insights into the genetics and immunobiology of relapsed/refractory follicular lymphoma

Although follicular lymphoma (FL) is traditionally classified as an indolent subtype of B cell non-Hodgkin lymphoma, clinical trajectories are often diverse based on unique disease biology, and many patients will eventually experience relapse of their disease. Furthermore, progression of disease within 24 months is associated with increased mortality rates for FL. In the last five years, we have witnessed an upsurge in the commercial availability of targeted therapies for relapsed/refractory (R/R) FL, including chimeric antigen receptor-T (CAR-T) products, bispecific T cell engagers (BiTEs), epigenetic modifier therapies, and next-generation Bruton tyrosine kinase (BTK) inhibitors. Furthermore, clinical trial options have increased tremendously and now include combinatorial strategies that exert synergy against malignant germinal center B cells. Here, we provide a 2024 update of novel therapeutic agents whose development has been informed by recent advances in the genetics and immunobiology of R/R FL. Specifically, we emphasize high-value targeted therapeutics, including anti-CD3 x anti-CD20 BiTEs and adoptive T cell therapies. We discuss prospects on selection and sequencing of BiTEs and CAR-T therapies for patients with R/R FL. We underscore the principles of FL pathobiology that are paving way for future drug discovery and shed insight into therapeutic targeting within nodal basins based on our increasing understanding of the FL microenvironment. Finally, we summarize how a greater knowledge of FL immunobiology can inform risk stratification and therapy selection on a personalized basis for R/R FL in 2025.

A meta-analysis to assess the risk of bleeding and thrombosis following chimeric antigen receptor T-cell therapy: Communication from the ISTH SSC Subcommittee on Hemostasis and Malignancy

BACKGROUND

Chimeric antigen receptor T-cell (CAR T-cell) therapy is increasingly utilized for treatment of hematologic malignancies. Hematologic toxicities including thrombosis and bleeding complications have been reported. Accurate estimates for thrombotic and bleeding outcomes are lacking.

OBJECTIVES

We performed a systematic review and meta-analysis in patients who received CAR T-cell therapy for an underlying hematologic malignancy with the objective to: a) assess the thrombosis and bleeding risk associated with CAR T-cell therapy, b) assess the impact of CRS and ICANS on the risks of thrombosis and bleeding, and c) assess the safety of anticoagulant or antiplatelet use in the period following treatment with CAR T-cell therapy.

METHODS

We searched MEDLINE, EMBASE, and Cochrane CENTRAL up to February 2022 for studies reporting thrombotic or bleeding outcomes in patients receiving CAR T-cell therapy. Pooled event rates were calculated using a random-effects model. We performed subgroup analyses stratified by follow-up duration, CAR T-cell target antigen, and underlying hematologic malignancy.

RESULTS

We included 47 studies with a total of 7040 patients. High heterogeneity between studies precluded reporting of overall pooled rates of thrombotic and bleeding events. In studies with follow-up duration of ≤6 months, the pooled incidence of venous thrombotic events was 2.4% (95% CI, 1.4%-3.4%; I2 = 0%) per patient-month, whereas the rate was 0.1% (95% CI, 0%-0.1%; I2 = 0%) per patient-month for studies with longer follow-up periods (>6 months). The pooled incidences of any bleeding events per patient-month in studies with follow-up duration of ≤6 months and >6 months were 1.9% (95% CI, 0.6%-3.1%; I2 = 78%) and 0.3% (95% CI: 0%-0.8%, I2 = 40%), respectively. Secondary analyses by CAR T-cell target antigen, underlying malignancy, and primary outcome of the studies did not reveal significant differences in the rates of thromboembolism, any bleeding events, or major bleeding events.

CONCLUSION

The risk of both thrombosis and bleeding following CAR T-cell therapy appears to be highest in the initial months following infusion.

Postinfusion PD-1+ CD8+ CAR T cells identify patients responsive to CD19 CAR T-cell therapy in non-Hodgkin lymphoma

ABSTRACT

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized treatment for relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). Robust biomarkers and a complete understanding of CAR T-cell function in the postinfusion phase remain limited. Here, we used a 37-color spectral flow cytometry panel to perform high dimensional single-cell analysis of postinfusion samples in 26 patients treated with CD28 costimulatory domain containing commercial CAR T cells for NHL and focused on computationally gated CD8+ CAR T cells. We found that the presence of postinfusion Programmed cell death protein 1 (PD-1)+ CD8+ CAR T cells at the day 14 time point highly correlated with the ability to achieve complete response (CR) by 6 months. Further analysis identified multiple subtypes of CD8+ PD-1+ CAR T cells, including PD-1+ T cell factor 1 (TCF1)+ stem-like CAR T cells and PD-1+ T-cell immunoglobulin and mucin-domain containing-3 (TIM3)+ effector-like CAR T cells that correlated with improved clinical outcomes such as response and progression-free survival. Additionally, we identified a subset of PD-1+ CD8+ CAR+ T cells with effector-like function that was increased in patients who achieved a CR and was associated with grade 3 or higher immune effector cell-associated neurotoxicity syndrome. Here, we identified robust biomarkers of response to CD28 CAR T cells and highlight the importance of PD-1 positivity in CD8+ CAR T cells after infusion in achieving CR.

CAR19 monitoring by peripheral blood immunophenotyping reveals histology-specific expansion and toxicity

ABSTRACT

Chimeric antigen receptor (CAR) T cells directed against CD19 (CAR19) are a revolutionary treatment for B-cell lymphomas (BCLs). CAR19 cell expansion is necessary for CAR19 function but is also associated with toxicity. To define the impact of CAR19 expansion on patient outcomes, we prospectively followed a cohort of 236 patients treated with CAR19 (brexucabtagene autoleucel or axicabtagene ciloleucel) for mantle cell lymphoma (MCL), follicular lymphoma, and large BCL (LBCL) over the course of 5 years and obtained CAR19 expansion data using peripheral blood immunophenotyping for 188 of these patients. CAR19 expansion was higher in patients with MCL than other lymphoma histologic subtypes. Notably, patients with MCL had increased toxicity and required fourfold higher cumulative steroid doses than patients with LBCL. CAR19 expansion was associated with the development of cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and the requirement for granulocyte colony-stimulating factor 14 days after infusion. Younger patients and those with elevated lactate dehydrogenase (LDH) had significantly higher CAR19 expansion. In general, no association between CAR19 expansion and LBCL treatment response was observed. However, when controlling for tumor burden, we found that lower CAR19 expansion in conjunction with low LDH was associated with improved outcomes in LBCL. In sum, this study finds CAR19 expansion principally associates with CAR-related toxicity. Additionally, CAR19 expansion as measured by peripheral blood immunophenotyping may be dispensable to favorable outcomes in LBCL.

Rapid response in relapsed follicular lymphoma to novel anti-CD19 CAR-T therapy with pseudo-progression and cytomegalovirus infection: A case report

CD19-directed chimeric antigen receptor (CAR) T cell therapy has been shown to achieve a considerably durable response in patients with refractory or relapsed B cell non-Hodgkin lymphomas. Most of these CARs were generated by lentivirus. With the exception of Yescarta and Tecartus, few patients with relapsed-/refractory- lymphoma have been treated clinically with a CARs using retroviral vector (RV). Here, we reported a relapsed/refractory grade 2 follicular lymphoma patient with multiple chemotherapy failures, and was treated with a novel CD19 CAR-T cell manufactured from a RV. After tumor burden was reduced with Obinutuzumab and Duvelisib, the patient was infused novel CD19 CAR-T cells at a dose of 3 × 106 cells/ kg. Then he experienced a rapid response and achieved almost complete remission by day 26. Only grade 2 CRS, bilateral submaxillary lymph node enlargement and cytomegalovirus (CMV) infection occurred without neurotoxicity, and the patient's condition improved after a series of symptomatic treatments. In addition, CAR copy number peaked at 532,350 copies/μg on day 15 and continued to expand for 5 months. This may be the first case report of RV preparation of novel CD19 CAR-T cells for direct treatment of recurrent follicular lymphoma. We will observe its long-term efficacy and conduct trials in more patients in the future.

A novel inhalable nanobody targeting IL-4Rα for the treatment of asthma

BACKGROUND

Inhalable biologics represent a promising approach to improve the efficacy and safety of asthma treatment. Although several mAbs targeting IL-4 receptor α chain (IL-4Rα) have been approved or are undergoing clinical trials, the development of inhalable mAbs targeting IL-4Rα presents significant challenges.

OBJECTIVE

Capitalizing on the distinctive advantages of nanobodies (Nbs) in maintaining efficacy during storage and administration, we sought to develop a novel inhalable IL-4Rα Nb for effectively treating asthma.

METHODS

Three IL-4Rα immunized Nb libraries were used to generate specific and functional IL-4Rα Nbs. LQ036, a bivalent Nb comprising 2 HuNb103 units, was constructed with a high affinity and specificity for human IL-4Rα. The efficacy, pharmacokinetics, and safety of inhaled LQ036 were evaluated in B-hIL4/hIL4RA humanized mice.

RESULTS

LQ036 inhibited secreted embryonic alkaline phosphatase reporter activity, inhibited TF-1 cell proliferation, and suppressed phosphorylated signal transducer and activator of transduction 6 in T cells from patients with asthma. Crystal structure analysis revealed a binding region similar to dupilumab but with higher affinity, leading to better efficacy in blocking the signaling pathway. HuNb103 competed with IL-4 and IL-13 for IL-4Rα binding. Additionally, LQ036 significantly inhibited ovalbumin-specific IgE levels in serum, CCL17 levels in bronchoalveolar lavage fluid, bronchial mucous cell hyperplasia, and airway goblet cell hyperplasia in B-hIL4/hIL4RA humanized mice. Inhaled LQ036 exhibited favorable pharmacokinetics, safety, and tissue distribution, with higher concentrations observed in the lungs and bronchi.

CONCLUSIONS

These findings from preclinical studies establish the safety and efficacy of inhaled LQ036, underscoring its potential as a pioneering inhalable biologic therapy for asthma.

Late events after anti-CD19 CAR T-cell therapy for relapsed/refractory B-cell non-Hodgkin lymphoma

Background

The short-term complications from chimeric antigen receptor T-cell therapy (CART) are well characterized, but the long-term complications still need to be further investigated. Therefore, herein, we will review the currently available literature published on the late adverse events following CART.

Methods

We reviewed published data available from pivotal trials and real-world experiences with anti-CD19 CART (CART19) for adults with lymphoma. We defined late events as occurring or persisting beyond 1 month after CART infusion. We focused our literature review on the following late-event outcomes post-CART19: cytopenia, immune reconstitution, infections, and subsequent malignancies.

Results

Grade 3-4 cytopenia beyond 30 days occurs in 30%-40% of patients and beyond 90 days in 3%-22% of patients and is usually managed with growth-factor and transfusion support, along with neutropenic prophylaxis. B-cell aplasia and hypogammaglobulinemia are expected on-target off-tumor effects of CART19, 44%-53% of patients have IgG < 400 mg/dL, and approximately 27%-38% of patients receive intravenous immunoglobulin (IVIG) replacement. Infections beyond the initial month from CART19 are not frequent and rarely severe, but they are more prevalent and severe when patients receive subsequent therapies post-CART19 for their underlying disease. Late neurotoxicity and neurocognitive impairment are uncommon, and other causes should be considered. T-cell lymphoma (TCL) after CART is an extremely rare event and not necessarily related to CAR transgene. Myeloid neoplasm is not rare post-CART, but unclear causality given heavily pretreated patient population is already at risk for therapy-related myeloid neoplasm.

Conclusion

CART19 is associated with clinically significant long-term effects such as prolonged cytopenia, hypogammaglobulinemia, and infections that warrant clinical surveillance, but they are mostly manageable with a low risk of non-relapse mortality. The risk of subsequent malignancies post-CART19 seems low, and the relationship with CART19 and/or prior therapies is unclear; but regardless of the possible causality, this should not impact the current benefit-risk ratio of CART19 for relapsed/refractory B-cell non-Hodgkin lymphoma (NHL).

The treatment of follicular lymphoma with CD19-directed chimeric antigen receptor T-cell therapy

Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma. Significant unmet need remains for patients with relapsed/refractory FL after ≥3 lines of prior therapy. While recent advancements have likely improved the survival of patients with FL, most patients will eventually relapse. The treatment of patients with FL after multiple relapses or those with refractory disease has historically led to lower overall response rates (ORR) and shorter progression-free survival (PFS) with each subsequent line of therapy. New treatments with high ORR and durable PFS are needed in this setting, particularly in patients that progress within 2 years of first line chemoimmunotherapy (POD24) and/or those refractory chemoimmunotherapy. Chimeric antigen receptor T-cell therapies targeting the B-cell antigen CD-19 have shown to be an efficacious treatment option for both heavily pretreated patients and/or patients with refractory FL, resulting in a high ORR and durable remissions.

CAR+ extracellular vesicles predict ICANS in patients with B cell lymphomas treated with CD19-directed CAR T cells

BACKGROUNDPredicting immune effector cell-associated neurotoxicity syndrome (ICANS) in patients infused with CAR T cells is still a conundrum. This complication, thought to be consequent to CAR T cell activation, arises a few days after infusion, when circulating CAR T cells are scarce and specific CAR T cell-derived biomarkers are lacking.METHODSCAR+ extracellular vesicle (CAR+EV) release was assessed in human CD19.CAR T cells cocultured with CD19+ target cells. A prospective cohort of 100 patients with B cell lymphoma infused with approved CD19.CAR T cell products was assessed for plasma CAR+EVs as biomarkers of in vivo CD19.CAR T cell activation. Human induced pluripotent stem cell-derived (iPSC-derived) neural cells were used as a model for CAR+EV-induced neurotoxicity.RESULTSIn vitro release of CAR+EVs occurs within 1 hour after target engagement. Plasma CAR+EVs are detectable 1 hour after infusion. A concentration greater than 132.8 CAR+EVs/μL at hour +1 or greater than 224.5 CAR+EVs/μL at day +1 predicted ICANS in advance of 4 days, with a sensitivity and a specificity outperforming other ICANS predictors. ENO2+ nanoparticles were released by iPSC-derived neural cells upon CAR+EV exposure and were increased in plasma of patients with ICANS.CONCLUSIONPlasma CAR+EVs are an immediate signal of CD19.CAR T cell activation, are suitable predictors of neurotoxicity, and may be involved in ICANS pathogenesis.TRIAL REGISTRATIONNCT04892433, NCT05807789.FUNDINGLife Science Hub-Advanced Therapies (financed by Health Ministry as part of the National Plan for Complementary Investments to the National Recovery and Resilience Plan [NRRP]: E.3 Innovative health ecosystem for APC fees and immunomonitoring).

Self-regulating CAR-T cells modulate cytokine release syndrome in adoptive T-cell therapy

Cytokine release syndrome (CRS) is a frequently observed side effect of chimeric antigen receptor (CAR)-T cell therapy. Here, we report self-regulating T cells that reduce CRS severity by secreting inhibitors of cytokines associated with CRS. With a humanized NSG-SGM3 mouse model, we show reduced CRS-related toxicity in mice treated with CAR-T cells secreting tocilizumab-derived single-chain variable fragment (Toci), yielding a safety profile superior to that of single-dose systemic tocilizumab administration. Unexpectedly, Toci-secreting CD19 CAR-T cells exhibit superior in vivo antitumor efficacy compared with conventional CD19 CAR-T cells. scRNA-seq analysis of immune cells recovered from tumor-bearing humanized mice revealed treatment with Toci-secreting CD19 CAR-T cells enriches for cytotoxic T cells while retaining memory T-cell phenotype, suggesting Toci secretion not only reduces toxicity but also significantly alters the overall T-cell composition. This approach of engineering T cells to self-regulate inflammatory cytokine production is a clinically compatible strategy with the potential to simultaneously enhance safety and efficacy of CAR-T cell therapy for cancer.

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.

Safety and Toxicity Profiles of CAR T Cell Therapy in Non-Hodgkin Lymphoma: A Systematic Review and Meta-Analysis

BACKGROUND

The application of CD19-directed chimeric antigen receptor T (CAR T) cell therapy has improved outcomes for thousands of patients with non-Hodgkin B cell lymphoma (NHL). The toxicities associated with various CAR T cell products, however, can be severe and difficult to anticipate.

METHODS

In this systematic review and meta-analysis, we set out to determine whether there are measurable differences in common toxicities, including cytokine release syndrome (CRS), immune effector cell associated neurotoxicity syndrome (ICANS), cytopenias, and infections, between CAR T products that are commercially available for the treatment of NHL.

RESULTS

After a stringent study selection process, we used a cohort of 1364 patients enrolled in 15 prospective clinical trials investigating the use of axicabtagene ciloleucel (axi-cel), lisocabtagene maraleucel (liso-cel), and tisagenlecleucel (tisa-cel). We found that the rates of CRS and ICANS were significantly higher with axi-cel as compared to both liso-cel and tisa-cel. Conversely, we demonstrated that rates of all-grade and severe neutropenia were significantly greater with liso-cel. Febrile neutropenia and all-grade infection rates did not differ significantly between products though rates of severe infection were increased with axi-cel.

CONCLUSIONS

Overall, this study serves as the first to delineate toxicity profiles associated with various available CAR T products. By better understanding associated toxicities, it may become possible to tailor therapies towards individual patients and anticipate the development of toxicities at earlier stages.

CAR T-cell therapy: A collaboration between authorized treatment centers and community oncologists

With the approval of the first CAR T-cell products for hematological malignancies in 2017, these autologous cell therapies have changed the treatment paradigm for patients with relapsed or refractory (r/r) non-Hodgkin lymphoma (NHL), who have a poor prognosis and few effective treatment options. Despite the demonstrated clinical benefit in patients with r/r diffuse large B-cell lymphoma, mantle cell lymphoma, and follicular lymphoma, many patients who are eligible for CAR T-cell therapies do not receive them or are treated with CAR T cells as a later line of therapy at advanced stages of disease. Several barriers exist for referring patients to an authorized treatment center (ATC) for CAR T-cell therapy. Although most patients with NHL are treated by community-based oncologists, educational gaps may exist for some community oncologists about the availability of CAR T-cell therapies in certain indications, the overall treatment process, and how they can access these therapies for their patients. In addition to navigation of the referral process from the community setting to the ATC, other barriers include timely identification of candidates eligible for CAR T-cell therapy and logistical and reimbursement concerns. Here, we examine the patient CAR T-cell experience, which begins and ends in the community setting, and identify and discuss opportunities for improved collaboration between community oncologists and ATC physicians to help address barriers to treatment and enhance patient outcomes. Treatment decisions for a patient's second or third line of therapy for NHL are critically important, owing to declining probabilities for favorable outcomes with each successive line of therapy. For patients who are eligible, CAR T-cell therapies should be considered as early as possible in their treatment course. A better understanding of the CAR T-cell process, the patient's experience, and the collaboration necessary for timely patient identification, better access, and successful outcomes will enable more patients to benefit from CAR T-cell therapies.

Optimizing Real-World Outcomes in High-Risk Relapsed/Refractory (r/r) FL with CAR-T Cell Therapy: A Vodcast and Case Example

Follicular lymphoma (FL) is often considered a chronic disease with frequent relapses, shortening both response duration and survival after every relapse. Selecting the most appropriate therapy at the right time within the treatment timeline is key to optimize outcomes. The aim of this vodcast, featuring Dr. Kai Hübel, is to outline the severity of FL by referring to a patient case as well as highlight chimeric antigen receptor (CAR)-T cells as an effective therapy in relapsed/refractory (r/r) FL. The patient was in their early 50s, diagnosed with FL in the early 2010s and presented with a third relapse. The patient complained of night sweats and fatigue but was still capable of self-care (Eastern Cooperative Oncology Group Performance Status Scale 2). The patient received eight cycles of rituximab-cyclophosphamide-doxorubicin-vincristine-prednisolone (R-CHOP), followed by irradiation and rituximab maintenance (first-line) and then received rituximab 4 × weekly, followed by rituximab maintenance (second-line). The patient relapsed during rituximab maintenance; the patient was rituximab refractory. The patient received six cycles of bendamustine/obinutuzumab followed by obinutuzumab maintenance. The patient relapsed during obinutuzumab maintenance, achieved a partial remission after irradiation and was switched to R/lenalidomide. Due to several high-risk features, CAR-T cell therapy was initiated. Dr. Hubel underlines how earlier treatment with CAR-T cell therapy would have been beneficial for this patient. Results of the ELARA trial as well as comparative studies have shown tisagenlecleucel to be more effective than standard of care in extensively pretreated r/r FL, including high-risk patients. In conclusion, CAR-T cell therapy is a promising therapy option for patients with multiply r/r FL. A vodcast feature is available for this article.

Severe anaphylaxis after chimeric antigen receptor T-cell injection: a case report

Anaphylactic reactions at the time of chimeric antigen receptor T (CAR-T) cell infusion are adverse events that have not been reported in pivotal clinical trials or in real-world series. We report the case of patient with severe anaphylaxis with cardiac arrest after tisagenlecleucel injection for Diffuse Large B cell Lymphoma, who recovered after resuscitation and intensive care treatment; we also conducted a Food and Drug Administration Adverse Event Reporting System database analysis and found several cases of severe anaphlyaxis after CAR-T cell injection. Although not reported in pivotal CAR-T cell studies, anaphylaxis can occur after CAR-T cell injection, highlighting the need to include anaphylaxis as a possible side effect in future studies.

The Glass Wall: Gendered Authorship Disparities in CD 19 and BCMA CAR-T Clinical Trials for Lymphoma and Myeloma

INTRODUCTION

Existing literature suggests that women are significantly underrepresented in the field of hematology-oncology. Women make up 35.6% of hematologists and data on females as site investigators for pivotal trials and authors in publications of pivotal trials in hematologic malignancies, specifically in the novel niche of Chimeric antigen receptor T cell (CAR-T), is sparse.

METHODS

We examined the proportion of women in pivotal trials, screening a total of 2180 studies from PubMed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. 2180 initially searched records were filtered by date (2017-2023) and clinical trial status, yielding 149 records. Following a manual review, we included 15 studies that led to the approval of or anticipated approval of CD19 and BCMA CAR-T therapies in lymphoid and plasma cell malignancies. We examined overall number of female authors, number of lead female authors, and ratio of all authors to female authors in the 15 trials, which were all high impact, cited on average 1314 times.

RESULTS

Of the 436 authors assessed, 132 were female, correlating to 29.5% female authorship. The only study with female authorship >50% was ELIANA, a 2017 pediatric study. 7 of the 15 studies had female lead authors; notably, 6 out of 7 of these studies were published in 2021 or later.

CONCLUSION

In conclusion, our data suggests gender iniquities for female investigators exist in the field of immune effector cell therapy. We suggest further investigation and strategies to decrease gendered authorship disparities.

CAR-T-Cell-Based Cancer Immunotherapies: Potentials, Limitations, and Future Prospects

Cancer encompasses various elements occurring at the cellular and genetic levels, necessitating an immunotherapy capable of efficiently addressing both aspects. T cells can combat cancer cells by specifically recognizing antigens on them. This innate capability of T cells has been used to develop cellular immunotherapies, but most of them can only target antigens through major histocompatibility complexes (MHCs). New gene-editing techniques such as clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (CRISPR-cas9) can precisely edit the DNA sequences. CRISPR-cas9 has made it possible to generate genetically engineered chimeric antigen receptors (CARs) that can overcome the problems associated with old immunotherapies. In chimeric antigen receptor T (CAR-T) cell therapy, the patient's T cells are isolated and genetically modified to exhibit synthetic CAR(s). CAR-T cell treatment has shown remarkably positive clinical outcomes in cancers of various types. Nevertheless, there are various challenges that reduce CAR-T effectiveness in solid tumors. It is required to address these challenges in order to make CAR-T cell therapy a better and safer option. Combining CAR-T treatment with other immunotherapies that target multiple antigens has shown positive outcomes. Moreover, recently generated Boolean logic-gated advanced CARs along with artificial intelligence has expanded its potential to treat solid tumors in addition to blood cancers. This review aims to describe the structure, types, and various methods used to develop CAR-T cells. The clinical applications of CAR-T cells in hematological malignancies and solid tumours have been described in detail. In addition, this discussion has addressed the limitations associated with CAR-T cells, explored potential strategies to mitigate CAR-T-related toxicities, and delved into future perspectives.

CAR-T Cells in Acute Myeloid Leukemia: Where Do We Stand?

Despite recent advances, the prognosis of acute myeloid leukemia (AML) remains unsatisfactory due to disease recurrence and the development of resistance to both conventional and novel therapies. Engineered T cells expressing chimeric antigen receptors (CARs) on their cellular surface represent one of the most promising anticancer agents. CAR-T cells are increasingly used in patients with B cell malignancies, with remarkable clinical results despite some immune-related toxicities. However, at present, the role of CAR-T cells in myeloid neoplasms, including AML, is extremely limited, as specific molecular targets for immune cells are generally lacking on AML blasts. Besides the paucity of dispensable targets, as myeloid antigens are often co-expressed on normal hematopoietic stem and progenitor cells with potentially intolerable myeloablation, the AML microenvironment is hostile to T cell proliferation due to inhibitory soluble factors. In addition, the rapidly progressive nature of the disease further complicates the use of CAR-T in AML. This review discusses the current state of CAR-T cell therapy in AML, including the still scanty clinical evidence and the potential approaches to overcome its limitations, including genetic modifications and combinatorial strategies, to make CAR-T cell therapy an effective option for AML patients.

Circulating Tumor DNA as a Complementary Prognostic Biomarker during CAR-T Therapy in B-Cell Non-Hodgkin Lymphomas

The emergence of CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the treatment paradigm for R/R B-cell NHLs. However, challenges persist in accurately evaluating treatment response and detecting early relapse, necessitating the exploration of novel biomarkers. Circulating tumor DNA (ctDNA) via liquid biopsy is a non-invasive tool for monitoring therapy efficacy and predicting treatment outcomes in B-NHL following CAR-T therapy. By overcoming the limitations of conventional imaging modalities, ctDNA assessments offer valuable insights into response dynamics, molecular mechanisms of resistance, and early detection of molecular relapse. Integration of ctDNA monitoring into clinical practice holds promise for personalized therapeutic strategies, guiding the development of novel targeted therapies, and enhancing patient outcomes. However, standardization of assay methodologies and consensus on clinical response metrics are imperative to unlock the full potential of ctDNA in the management of B-NHL. Prospective validation of ctDNA in clinical trials is necessary to establish its role as a complementary decision aid.

Outpatient administration of CAR T-cell therapy: a focused review with recommendations for implementation in community based centers

Chimeric Antigen Receptor T-cell (CAR-T) therapy has transformed the treatment landscape for hematological malignancies, showing high efficacy in patients with relapsed or refractory (R/R) disease and otherwise poor prognosis in the pre-CAR-T era. These therapies have been usually administered in the inpatient setting due to the risk of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). However, there is a growing interest in the transition to outpatient administration due to multiple reasons. We review available evidence regarding safety and feasibility of outpatient administration of CD19 targeted and BCMA targeted CAR T-cell therapy with an emphasis on the implementation of outpatient CAR-T programs in community-based centers.

B-cell non-Hodgkin lymphomas

B-cell lymphomas occur with an incidence of 20 new cases per 100 000 people per year in high-income countries. They can affect any organ and are characterised by heterogeneous clinical presentations and courses, varying from asymptomatic, to indolent, to very aggressive cases. Since the topic of B-cell non-Hodgkin lymphomas was last reviewed in The Lancet in 2017, a deeper understanding of the biological background of this heterogeneous group of malignancies, the availability of new diagnostic methods, and the development and implementation of new targeted and immunotherapeutic approaches have improved our ability to treat patients. This Seminar provides an overview of the pathobiology, classification, and prognostication of B-cell non-Hodgkin lymphomas and summarises the current knowledge and standard of care regarding biology and clinical management of the most common subtypes of mature B-cell non-Hodgkin lymphomas. It also highlights new findings in deciphering the molecular background of disease development and the implementation of new therapeutic approaches, particularly those targeting the immune system.

Remission after CAR T-cell therapy: Do lymphoma patients recover a normal life?

Chimeric antigen receptor T cells (CAR T cells) can induce prolonged remission in a substantial subset of patients with relapse/refractory lymphoma. However, little is known about patients' life after CAR T-cell therapy. We prospectively assessed the multidimensional recovery of lymphoma patients in remission, before leukapheresis, before CAR T-cell infusion, and 3, 6, and 12 months thereafter. Validated tools were used to measure lymphoma-related and global health-related quality of life (HRQoL; Functional Assessment of Cancer Therapy-Lymphoma [FACT-Lym] and EQ-5D-5L), cognitive complaint (FACT-Cognition), fatigue (FACIT-Fatigue subscale), psychological status (Hospital Anxiety and Depression Scale, Post-Traumatic Check List Scale), and sexuality (Relationship and Sexuality Scale). Beyond 12 months of remission, we also surveyed physical, professional, sexual, and general life status. At 3, 6, and 12 months, 53, 35, and 23 patients were evaluable, respectively. Improvement in lymphoma-related HRQoL was clinically relevant at 3, 6, and 12 months with a mean change from baseline of 10.9 (95% confidence interval [CI]: 5.8; 16.1), 12.2 (95% CI: 4.2; 20.1), and 11.72 (95% CI: 2.06; 21.38), respectively. Improvement in global HRQoL, fatigue, and anxiety was clinically relevant, but 20%-40% of patients experienced persistent fatigue, psychological distress, and cognitive complaints over time. Beyond 12 months after CAR T cells, 81.8% of 22 evaluable patients were satisfied with their daily life. Physical activity, professional, sexual, and global well-being had returned to prediagnosis levels in nearly half of the patients. We found an improvement in HRQoL after CAR T-cell therapy including anxiety, depression, sexual satisfaction, and general well-being. However, not all patients recover a "normal life." Further research is needed to determine which patients are at risk of quality-of-life impairment to improve recovery after CAR T-cell infusion.

CAR-T Cells in Chronic Lymphocytic Leukemia

The treatment outcomes of patients with chronic lymphocytic leukemia (CLL) have considerably improved with the introduction of targeted therapies based on Bruton kinase inhibitors (BTKIs), venetoclax, and anti-CD20 monoclonal antibodies. However, despite these consistent improvements, patients who become resistant to these agents have poor outcomes and need new and more efficacious therapeutic strategies. Among these new treatments, a potentially curative approach consists of the use of chimeric antigen receptor T (CAR-T) cell therapy, which achieved remarkable success in various B-cell malignancies, including B-cell Non-Hodgkin Lymphomas (NHLs) and B-acute lymphoblastic Leukemia (ALL). However, although CAR-T cells were initially used for the treatment of CLL, their efficacy in CLL patients was lower than in other B-cell malignancies. This review analyses possible mechanisms of these failures, highlighting some recent developments that could offer the perspective of the incorporation of CAR-T cells in treatment protocols for relapsed/refractory CLL patients.

Current Challenges in Chimeric Antigen Receptor T-cell Therapy in Patients With B-cell Lymphoid Malignancies

Chimeric antigen receptor (CAR) T-cell therapy is a promising immunotherapy based on genetically engineered T cells derived from patients. The introduction of CAR T-cell therapy has changed the treatment paradigm of patients with B-cell lymphoid malignancies. However, challenging issues including managing life-threatening toxicities related to CAR T-cell infusion and resistance to CAR T-cell therapy, leading to progression or relapse, remain. This review summarizes the issues with currently approved CAR T-cell therapies for patients with relapsed or refractory B-cell lymphoid malignancies, including lymphoma and myeloma. We focus on unique toxicities after CAR T-cell therapy, such as cytokine-related events and hematological toxicities, and the mechanisms underlying post-CAR T-cell failure.

The potential and promise for clinical application of adoptive T cell therapy in cancer

Adoptive cell therapy has revolutionized cancer treatment, especially for hematologic malignancies. T cells are the most extensively utilized cells in adoptive cell therapy. Currently, tumor-infiltrating lymphocytes, T cell receptor-transgenic T cells and chimeric antigen receptor T cells are the three main adoptive T cell therapies. Tumor-infiltrating lymphocytes kill tumors by reinfusing enlarged lymphocytes that naturally target tumor-specific antigens into the patient. T cell receptor-transgenic T cells have the ability to specifically destroy tumor cells via the precise recognition of exogenous T cell receptors with major histocompatibility complex. Chimeric antigen receptor T cells transfer genes with specific antigen recognition structural domains and T cell activation signals into T cells, allowing T cells to attack tumors without the assistance of major histocompatibility complex. Many barriers have been demonstrated to affect the clinical efficacy of adoptive T cell therapy, such as tumor heterogeneity and antigen loss, hard trafficking and infiltration, immunosuppressive tumor microenvironment and T cell exhaustion. Several strategies to improve the efficacy of adoptive T cell therapy have been explored, including multispecific chimeric antigen receptor T cell therapy, combination with immune checkpoint blockade, targeting the immunosuppressive tumor microenvironment, etc. In this review, we will summarize the current status and clinical application, followed by major bottlenecks in adoptive T cell therapy. In addition, we will discuss the promising strategies to improve adoptive T cell therapy. Adoptive T cell therapy will result in even more incredible advancements in solid tumors if the aforementioned problems can be handled.

The role of chimeric antigen receptor T cells targeting more than one antigen in the treatment of B-cell malignancies

Several products containing chimeric antigen receptor T cells targeting CD19 (CART19) have been approved for the treatment of patients with relapsed/refractory non-Hodgkin's lymphoma (NHL) and acute lymphoblastic leukaemia (ALL). Despite very impressive response rates, a significant percentage of patients experience disease relapse and die of progressive disease. A major cause of CART19 failure is loss or downregulation of CD19 expression in tumour cells, which has prompted a myriad of novel strategies aimed at targeting more than one antigen (e.g. CD19 and CD20 or CD22). Dual targeting can the accomplished through co-administration of two separate products, co-transduction with two different vectors, bicistronic cassettes or tandem receptors. In this manuscript, we review the pros and cons of each strategy and the clinical results obtained so far.