The present and future for CAR-T cell therapy in adult B-cell ALL.

Chimeric Antigen Receptor T-cell therapy (CAR-T) targeting CD19 has transformed the management of relapsed/refractory (r/r) B-Acute Lymphoblastic Leukemia (B-ALL), with FDA approval of tisagenlecleucel (tisa-cel) for pediatric/young adult patients and brexucabtagene autoleucel (brexu-cel) for adults. Efficacy is contingent upon several factors including disease burden. Emerging data suggests that bridging therapy, lymphodepletion and for some patients, consolidation therapy have an important role in the success of treatment. Further, strategies to define and manage immunotoxic side effects including hematotoxicity is critical to safe delivery. Advancements in CAR-T design beyond CD19 represent an ongoing therapeutic evolution. Overall, CAR-T therapy signifies a paradigm shift in B-ALL management, with the potential for improved remission and survival in a historically challenging patient population.

Dual targeting of CD19 and CD22 with bicistronic CAR-T cells in patients with relapsed/refractory large B-cell lymphoma.

Relapse after CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy for large B-cell lymphoma (LBCL) is commonly ascribed to antigen loss or CAR-T exhaustion. Multiantigen targeting and programmed cell death protein-1 blockade are rational approaches to prevent relapse. Here, we test CD19/22 dual-targeting CAR-T (AUTO3) plus pembrolizumab in relapsed/refractory LBCL (NCT03289455). End points include toxicity (primary) and response rates (secondary). Fifty-two patients received AUTO3 and 48/52 received pembrolizumab. Median age was 59 years (range, 27-83), 46/52 had stage III/ IV disease and median follow-up was 21.6 months. AUTO3 was safe; grade 1-2 and grade 3 cytokine release syndrome affected 18/52 (34.6%) and 1/52 (1.9%) patients, neurotoxicity arose in 4 patients (2/4, grade 3-4), and hemophagocytic lymphohistiocytosis affected 2 patients. Outpatient administration was tested in 20 patients, saving a median of 14 hospital days per patient. Overall response rates were 66% (48.9%, complete response [CR]; 17%, partial response). Median duration of remission (DOR) for CR patients was not reached and for all responding patients was 8.3 months (95% confidence interval [CI]: 3.0-not evaluable). 54.4% (CI: 32.8-71.7) of CR patients and 42.6% of all responding patients were projected to remain progression-free at ≥12 months. AUTO3 ± pembrolizumab for relapsed/refractory LBCL was safe and delivered durable remissions in 54.4% of complete responders, associated with robust CAR-T expansion. Neither dual-targeting CAR-T nor pembrolizumab prevented relapse in a significant proportion of patients, and future developments include next-generation-AUTO3, engineered for superior expansion in vivo, and selection of CAR binders active at low antigen densities.

Immune effector cell-associated hematotoxicity: EHA/EBMT consensus grading and best practice recommendations.

Hematological toxicity is the most common adverse event after chimeric antigen receptor (CAR) T-cell therapy. Cytopenias can be profound and long-lasting and can predispose for severe infectious complications. In a recent worldwide survey, we demonstrated that there remains considerable heterogeneity in regard to current practice patterns. Here, we sought to build consensus on the grading and management of immune effector cell-associated hematotoxicity (ICAHT) after CAR T-cell therapy. For this purpose, a joint effort between the European Society for Blood and Marrow Transplantation (EBMT) and the European Hematology Association (EHA) involved an international panel of 36 CAR T-cell experts who met in a series of virtual conferences, culminating in a 2-day meeting in Lille, France. On the basis of these deliberations, best practice recommendations were developed. For the grading of ICAHT, a classification system based on depth and duration of neutropenia was developed for early (day 0-30) and late (after day +30) cytopenia. Detailed recommendations on risk factors, available preinfusion scoring systems (eg, CAR-HEMATOTOX score), and diagnostic workup are provided. A further section focuses on identifying hemophagocytosis in the context of severe hematotoxicity. Finally, we review current evidence and provide consensus recommendations for the management of ICAHT, including growth factor support, anti-infectious prophylaxis, transfusions, autologous hematopoietic stem cell boost, and allogeneic hematopoietic cell transplantation. In conclusion, we propose ICAHT as a novel toxicity category after immune effector cell therapy, provide a framework for its grading, review literature on risk factors, and outline expert recommendations for the diagnostic workup and short- and long-term management.

A novel predictive algorithm to personalize autologous T-cell harvest for chimeric antigen receptor T-cell manufacture.

BACKGROUND AIMS: The most widely accepted starting materials for chimeric antigen receptor T-cell manufacture are autologous CD3+ T cells obtained via the process of leukapheresis, also known as T-cell harvest. As this treatment modality gains momentum and apheresis units struggle to meet demand for harvest slots, strategies to streamline this critical step are warranted. METHODS: This retrospective review of 262 T-cell harvests, with a control cohort of healthy donors, analyzed the parameters impacting CD3+ T-cell yield in adults with B-cell malignancies. The overall aim was to design a novel predictive algorithm to guide the required processed blood volume (PBV) (L) on the apheresis machine to achieve a specific CD3+ target yield. RESULTS: Factors associated with CD3+ T-cell yield on multivariate analysis included peripheral blood CD3+ count (natural log, ×109/L), hematocrit (HCT) and PBV with coefficients of 0.86 (95% confidence interval [CI], 0.80-0.92, P < 0.001), 1.30 (95% CI, 0.51-2.08, P = 0.001) and 0.09 (95% CI, 0.07-0.11, P < 0.001), respectively. The authors' model, incorporating CD3+ cell count, HCT and PBV (L), with an adjusted R2 of 0.87 and root-mean-square error of 0.26 in the training dataset, was highly predictive of CD3+ cell yield in the testing dataset. An online application to estimate PBV using this algorithm can be accessed at https://cd3yield.shinyapps.io/cd3yield/. CONCLUSIONS: The authors propose a transferrable model that incorporates clinical and laboratory variables accessible pre-harvest for use across the field of T-cell therapy. Pending further validation, such a model may be used to generate an individual leukapheresis plan and streamline the process of cell harvest, a well-recognized bottleneck in the industry.

Release Assays and Potency Assays for CAR T-Cell Interventions.

Chimeric antigen receptor (CAR) T-cells are considered "living drugs" and offer a compelling alternative to conventional anticancer therapies. Briefly, T-cells are redirected, using gene engineering technology, toward a specific cancer cell surface target antigen via a synthetic chimeric antigen receptor (CAR) protein. CARs have a modular design comprising four main structures: an antigen-binding domain, a hinge region, a transmembrane domain, and one or more intracellular signaling domains for T-cell activation. A major challenge in the CAR T-cell manufacturing field is balancing product quality with scalability and cost-effectiveness, especially when transitioning from an academic clinical trial into a marketed product, to be implemented across many collection, manufacturing, and treatment sites. Achieving product consistency while circumnavigating the intrinsic variability associated with autologous products is an additional barrier. To overcome these limitations, a robust understanding of the product and its biological actions is crucial to establish a target product profile with a defined list of critical quality attributes to be assessed for each batch prior to product certification. Additional challenges arise as the field progresses, such as new safety considerations associated with the use of allogenic T-cells and genome editing tools. In this chapter, we will discuss the release and potency assays required for CAR T-cell manufacturing, covering their relevance, current challenges, and future perspectives.

A national service for delivering CD19 CAR-Tin large B-cell lymphoma - The UK real-world experience.

CD19 CAR-T have emerged as a new standard treatment for relapsed/refractory (r/r) large B-cell lymphoma (LBCL). CAR-T real-world (RW) outcomes published to date suggest significant variability across countries. We provide results of a large national cohort of patients intended to be treated with CAR-T in the UK. Consecutive patients with r/r LBCL approved for CAR-T by the National CAR-T Clinical Panel between December 2018 and November 2020 across all UK CAR-T centres were included. 404/432 patients were approved [292 axicabtagene ciloleucel (axi-cel), 112 tisagenlecleucel (tisa-cel)], 300 (74%) received the cells. 110/300 (38.3%) patients achieved complete remission (CR) at 6 months (m). The overall response rate was 77% (52% CR) for axi-cel, 57% (44% CR) for tisa-cel. The 12-month progression-free survival was 41.8% (axi-cel) and 27.4% (tisa-cel). Median overall survival for the intention-to-treat population was 10.5 m, 16.2 m for infused patients. The incidence of grade ≥3 cytokine release syndrome and neurotoxicity were 7.6%/19.6% for axi-cel and 7.9%/3.9% for tisa-cel. This prospective RW population of CAR-T eligible patients offers important insights into the clinical benefit of CD19 CAR-T in LBCL in daily practice. Our results confirm long-term efficacy in patients receiving treatment similar to the pivotal trials, but highlight the significance of early CAR-T failure.

Cardiovascular Events Associated with Chimeric Antigen Receptor T Cell Therapy: Cross-Sectional FDA Adverse Events Reporting System Analysis.

Chimeric antigen receptor (CAR) T cell therapy is approved in the United States for the treatment of acute lymphocytic leukemia and aggressive B cell lymphomas. Multiple cardiovascular adverse events (CVEs) associated with CAR-Ts have been observed in small studies, but no large-scale studies exist. Leveraging the Food and Drug Administration (FDA) Adverse Events Reporting System (FAERS), we identified all reported adverse events (AEs) associated with CAR-T therapy (tisagenlecleucel and axicabtagene ciloleucel) from 2017 to 2019. Reports with missing age and sex were excluded. CVEs were classified into arrhythmias, heart failure (HF), myocardial infarction (MI), and other CVEs. Logistic regression and hierarchical clustering were used to identify factors associated with CVEs. A total of 996 reported AEs were observed (39.1% associated with tisagenlecleucel and 60% with axicabtagene ciloleucel). Of all patients experiencing AEs, the median age was 54 (interquartile range, 21 to 65) years; 38.9% were females. In total, 19.7% (196) of all AEs reported to the FDA were CVEs. The most common CVEs were arrhythmia (77.6%), followed by HF (14.3%) and MI (0.5%). In adjusted analysis a positive association was observed between those presenting with CVE with neurotoxicity (odds ratio, 1.76; 95% confidence interval, 1.20 to 2.60; P = .004). Additionally, when both CVE and cytokine release syndrome (CRS) are present, neurotoxicity is the most common noncardiac AE, which clusters with them (Jaccard similarity: 73.1). The mortality rate was 21.1% overall but 30.1% for those reporting CVEs. In FAERS, reported CVEs with CAR-T are associated with high reported mortality. The development of either CRS or neurotoxicity should prompt vigilance for cardiovascular events.

Clinical outcomes and risk factors for severe COVID-19 in patients with haematological disorders receiving chemo- or immunotherapy.

Haematology patients receiving chemo- or immunotherapy are considered to be at greater risk of COVID-19-related morbidity and mortality. We aimed to identify risk factors for COVID-19 severity and assess outcomes in patients where COVID-19 complicated the treatment of their haematological disorder. A retrospective cohort study was conducted in 55 patients with haematological disorders and COVID-19, including 52 with malignancy, two with bone marrow failure and one immune-mediated thrombotic thrombocytopenic purpura (TTP). COVID-19 diagnosis coincided with a new diagnosis of a haematological malignancy in four patients. Among patients, 82% were on systemic anti-cancer therapy (SACT) at the time of COVID-19 diagnosis. Of hospitalised patients, 37% (19/51) died while all four outpatients recovered. Risk factors for severe disease or mortality were similar to those in other published cohorts. Raised C-reactive protein at diagnosis predicted an aggressive clinical course. The majority of patients recovered from COVID-19, despite receiving recent SACT. This suggests that SACT, where urgent, should be administered despite intercurrent COVID-19 infection, which should be managed according to standard pathways. Delay or modification of therapy should be considered on an individual basis. Long-term follow-up studies in larger patient cohorts are required to assess the efficacy of treatment strategies employed during the pandemic.

RNA-seq of newly diagnosed patients in the PADIMAC study leads to a bortezomib/lenalidomide decision signature.

Improving outcomes in multiple myeloma will involve not only development of new therapies but also better use of existing treatments. We performed RNA sequencing on samples from newly diagnosed patients enrolled in the phase 2 PADIMAC (Bortezomib, Adriamycin, and Dexamethasone Therapy for Previously Untreated Patients with Multiple Myeloma: Impact of Minimal Residual Disease in Patients with Deferred ASCT) study. Using synthetic annealing and the large margin nearest neighbor algorithm, we developed and trained a 7-gene signature to predict treatment outcome. We tested the signature in independent cohorts treated with bortezomib- and lenalidomide-based therapies. The signature was capable of distinguishing which patients would respond better to which regimen. In the CoMMpass data set, patients who were treated correctly according to the signature had a better progression-free survival (median, 20.1 months vs not reached; hazard ratio [HR], 0.40; confidence interval [CI], 0.23-0.72; P = .0012) and overall survival (median, 30.7 months vs not reached; HR, 0.41; CI, 0.21-0.80; P = .0049) than those who were not. Indeed, the outcome for these correctly treated patients was noninferior to that for those treated with combined bortezomib, lenalidomide, and dexamethasone, arguably the standard of care in the United States but not widely available elsewhere. The small size of the signature will facilitate clinical translation, thus enabling more targeted drug regimens to be delivered in myeloma.

Neurotoxicity-CAR T-cell therapy: what the neurologist needs to know.

Chimeric antigen receptor (CAR) T-cell therapy is one of the most innovative therapies for haematological malignancies to emerge in a generation. Clinical studies have shown that a single dose of CAR T-cells can deliver durable clinical remissions for some patients with B-cell cancers where conventional therapies have failed.A significant complication of CAR therapy is the immune effector cell-associated neurotoxicity syndrome (ICANS). This syndrome presents a continuum from mild tremor to cerebral oedema and in a minority of cases, death. Management of ICANS is mainly supportive, with a focus on seizure prevention and attenuation of the immune system, often using corticosteroids. Parallel investigation to exclude other central nervous system pathologies (infection, disease progression) is critical. In this review, we discuss current paradigms around CAR T-cell therapy, with a focus on appropriate investigation and management of ICANS.

Manufacturing chimeric antigen receptor T cells: issues and challenges.

Clinical trials of adoptively transferred CD19 chimeric antigen receptor (CAR) T cells have delivered unprecedented responses in patients with relapsed refractory B-cell malignancy. These results have prompted Food and Drug Administration (FDA) approval of two CAR T-cell products in this high-risk patient population. The widening range of indications for CAR T-cell therapy and increasing patient numbers present a significant logistical challenge to manufacturers aiming for reproducible delivery systems for high-quality clinical CAR T-cell products. This review discusses current and novel CAR T-cell processing methodologies and the quality control systems needed to meet the increasing clinical demand for these exciting new therapies.

CAR-T cell manufacturing landscape-Lessons from the past decade and considerations for early clinical development.

CAR-T cell therapies have consolidated their position over the last decade as an effective alternative to conventional chemotherapies for the treatment of a number of hematological malignancies. With an exponential increase in the number of commercial therapies and hundreds of phase 1 trials exploring CAR-T cell efficacy in different settings (including autoimmunity and solid tumors), demand for manufacturing capabilities in recent years has considerably increased. In this review, we explore the current landscape of CAR-T cell manufacturing and discuss some of the challenges limiting production capacity worldwide. We describe the latest technical developments in GMP production platform design to facilitate the delivery of a range of increasingly complex CAR-T cell products, and the challenges associated with translation of new scientific developments into clinical products for patients. We explore all aspects of the manufacturing process, namely early development, manufacturing technology, quality control, and the requirements for industrial scaling. Finally, we discuss the challenges faced as a small academic team, responsible for the delivery of a high number of innovative products to patients. We describe our experience in the setup of an effective bench-to-clinic pipeline, with a streamlined workflow, for implementation of a diverse portfolio of phase 1 trials.

Current Treatment Options for Renal Cell Carcinoma: Focus on Cell-Based Immunotherapy.

Renal cell carcinoma (RCC) affects over 400,000 patients globally each year, and 30% of patients present with metastatic disease. Current standard of care therapy for metastatic RCC involve TKIs and ICIs, including combinatorial strategies, but this offers only modest clinical benefit. Novel treatment approaches are warranted, and cell-based immunotherapies for RCC hold significant promise. These are currently being tested in the pre-clinical setting and in early phase clinical trials. Here, we review the landscape of cellular immunotherapy for RCC in the context of currently available therapies, with a particular focus on defining the current best antigenic targets, the range of cell therapy products being explored in RCC, and how advanced engineering solutions may further enhance these therapies in the RCC space.

Mucormycosis after CD19 chimeric antigen receptor T-cell therapy: results of a US Food and Drug Administration adverse events reporting system analysis and a review of the literature.

Chimeric antigen receptor (CAR) T-cell therapy leads to durable remissions in relapsed B-cell cancers, but treatment-associated immunocompromise leads to a substantial morbidity and mortality risk from atypical infection. Mucormycosis is an aggressive and invasive fungal infection with a mortality risk of 40-80% in patients with haematological malignancies. In this Grand Round, we report a case of mucormycosis in a 54-year-old patient undergoing CAR T-cell therapy who reached complete clinical control of Mucorales with combined aggressive surgical debridement, antifungal pharmacotherapy, and reversal of underlying risk factors, but with substantial morbidity from extensive oro-facial surgery affecting the patient's speech and swallowing. For broader context, we present our case alongside an US Food and Drugs Administration adverse events reporting database analysis and a review of the literature to fully evaluate the clinical burden of mucormycosis in patients treated with CAR T-cell therapy. We discuss epidemiology, clinical features, diagnostic tools, and current frameworks for treatment and prophylaxis. We did this analysis to promote increased vigilance for mucormycosis among physicians specialising in CAR T-cell therapy and microbiologists and to illustrate the importance of early initiation of therapy to effectively manage this condition. Mucormycosis prevention and early diagnosis, through targeted surveillance and mould prevention in patients at highest risk and Mucorales-specific screening assays, is likely to be key to improving outcomes in patients treated with CAR T-cell therapy.

Single-centre experience of implementing physiotherapist-led prehabilitation for chimeric antigen receptor T cell therapy.

Introduction: This report outlines the evaluation of physiotherapist-led prehabilitation/rehabilitation for recipients of chimeric antigen receptor T (CAR-T) cell therapy. Methods: A hybrid approach was used, incorporating in-person assessment of quality of life and functional capacity (6-min walk test and timed sit-to-stand test), and a personalised home exercise programme with remotely delivered physiotherapist support pre/post-admission. Results: Functional deficits were prevalent at referral for CAR-T. Prehabilitation and rehabilitation were highly acceptable to patients, and improvements in functional capacity were documented pre-admission. Conclusion: This data highlights the importance of pre-CAR-T functional assessment and prehabilitation to optimise preparation and recovery.