Commercial anti-CD19 CAR T cell therapy for patients with relapsed/refractory aggressive B cell lymphoma in a European center

How can we improve the successful identification of patients suitable for CAR-T cell therapy?

INTRODUCTION

In recent years, chimeric antigen receptor T (CAR-T) cell therapy has resulted in a breakthrough in the treatment of patients with refractory or relapsed hematological malignancies. However, the identification of patients suitable for CAR-T cell therapy needs to be improved.

AREAS COVERED

CAR-T cell therapy has demonstrated excellent efficacy in hematological malignancies; however, views on determining when to apply CAR-T cells in terms of the evaluation of patient characteristics remain controversial.

EXPERT OPINION

We reviewed the current feasibility and challenges of CAR-T cell therapy in the most common hematological malignancies and classified them according to the disease type and treatment priority, to guide clinicians and researchers in applying and investigating CAR-T cells furtherly.

Chimeric antigen receptor T-cell therapy for haematological malignancies: Insights from fundamental and translational research to bedside practice

Autologous chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of lymphoid malignancies, leading to the approval of CD19-CAR T cells for B-cell lymphomas and acute leukaemia, and more recently, B-cell maturation antigen-CAR T cells for multiple myeloma. The long-term follow-up of patients treated in the early clinical trials demonstrates the possibility for long-term remission, suggesting a cure. This is associated with a low incidence of significant long-term side effects and a rapid improvement in the quality of life for responders. In contrast, other types of immunotherapies require prolonged treatments or carry the risk of long-term side effects impairing the quality of life. Despite impressive results, some patients still experience treatment failure or ultimately relapse, underscoring the imperative to improve CAR T-cell therapies and gain a better understanding of their determinants of efficacy to maximize positive outcomes. While the next-generation of CAR T cells will undoubtingly be more potent, there are already opportunities for optimization when utilizing the currently available CAR T cells. This review article aims to summarize the current evidence from clinical, translational and fundamental research, providing clinicians with insights to enhance their understanding and use of CAR T cells.

Anti-CD19 chimeric antigen receptor T-cell therapy in older patients with relapsed or refractory large B-cell lymphoma: A multicenter study

Chimeric antigen receptor T-cell (CAR-T) therapy, despite being a potentially curative therapy in relapsed or refractory (RR) large B-cell lymphoma (LBCL), remains underutilized in older patients due to limited clinical data. We therefore studied the safety and efficacy of CAR-T therapy in older patients with RR LBCL in the real-world setting. Patients aged ≥65 years with RR LBCL, treated with anti-CD19 CAR-T therapy at 7 US institutions were included in this multicenter, retrospective, observational study. In total, 226 patients were included. Median age at infusion was 71 years (range 65-89). Best objective and complete response rates were 86% and 62%, respectively. Median follow-up after infusion was 18.3 months. The median progression-free survival (PFS) was 6.9 months, with 6- and 12-month PFS estimates of 54% and 44%, respectively. The nonrelapse mortality (NRM) rate was 10.9% at day 180, primarily due to infections, and not impacted by the age groups. Grade ≥3 cytokine release syndrome and neurotoxicity occurred in 7% and 26%, respectively. In univariate analysis, no significant difference in PFS was seen regardless of the age groups or CAR-T type, whereas ECOG PS ≥2, elevated LDH, bulky disease, advanced stage, extranodal involvement, the need for bridging therapy, and prior bendamustine exposure were associated with shorter PFS. These findings support the use of CAR-T in older patients, including those aged ≥80 years. The age at CAR-T therapy did not influence safety, survival, and NRM outcomes. Older patients should not be excluded from receiving CAR-T therapy solely based on their chronological age.

CD19 CAR T cells for B cell malignancies: a systematic review and meta-analysis focused on clinical impacts of CAR structural domains, manufacturing conditions, cellular product, doses, patient's age, and tumor types

CD19-targeted chimeric antigen receptors (CAR) T cells are one of the most remarkable cellular therapies for managing B cell malignancies. However, long-term disease-free survival is still a challenge to overcome. Here, we evaluated the influence of different hinge, transmembrane (TM), and costimulatory CAR domains, as well as manufacturing conditions, cellular product type, doses, patient's age, and tumor types on the clinical outcomes of patients with B cell cancers treated with CD19 CAR T cells. The primary outcome was defined as the best complete response (BCR), and the secondary outcomes were the best objective response (BOR) and 12-month overall survival (OS). The covariates considered were the type of hinge, TM, and costimulatory domains in the CAR, CAR T cell manufacturing conditions, cell population transduced with the CAR, the number of CAR T cell infusions, amount of CAR T cells injected/Kg, CD19 CAR type (name), tumor type, and age. Fifty-six studies (3493 patients) were included in the systematic review and 46 (3421 patients) in the meta-analysis. The overall BCR rate was 56%, with 60% OS and 75% BOR. Younger patients displayed remarkably higher BCR prevalence without differences in OS. The presence of CD28 in the CAR's hinge, TM, and costimulatory domains improved all outcomes evaluated. Doses from one to 4.9 million cells/kg resulted in better clinical outcomes. Our data also suggest that regardless of whether patients have had high objective responses, they might have survival benefits from CD19 CAR T therapy. This meta-analysis is a critical hypothesis-generating instrument, capturing effects in the CD19 CAR T cells literature lacking randomized clinical trials and large observational studies.

Biomarkers of outcome in patients undergoing CD19 CAR-T therapy for large B cell lymphoma

CD19-directed autologous chimeric antigen receptor T cell (CAR-T) therapy has transformed the management of relapsed/refractory (R/R) large B cell lymphoma (LBCL). Initially approved in the third line and beyond setting, CAR-T is now standard of care (SOC) for second-line treatment in patients with refractory disease or early relapse (progression within 12 months) following primary chemoimmunotherapy. Despite becoming SOC, most patients do not achieve complete response, and long-term cure is only observed in approximately 40% of patients. Accordingly, there is an urgent need to better understand the mechanisms of treatment failure and to identify patients that are unlikely to benefit from SOC CAR-T. The field needs robust biomarkers to predict treatment outcome, as better understanding of prognostic factors and mechanisms of resistance can inform on the design of novel treatment approaches for patients predicted to respond poorly to SOC CAR-T. This review aims to provide a comprehensive overview of clinical, molecular, imaging, and cellular features that have been shown to influence outcomes of CAR-T therapy in patients with R/R LBCL.

[18F]FDG PET/CT for prognosis and toxicity prediction of diffuse large B-cell lymphoma patients with chimeric antigen receptor T-cell therapy

PURPOSE

Chimeric antigen receptor (CAR) T-cell therapy has been confirmed to benefit patients with relapsed and/or refractory diffuse large B-cell lymphoma (DLBCL). It is important to provide precise and timely predictions of the efficacy and toxicity of CAR T-cell therapy. In this study, we evaluated the value of [18F]fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) combining with clinical indices and laboratory indicators in predicting outcomes and toxicity of anti-CD19 CAR T-cell therapy for DLBCL patients.

METHODS

Thirty-eight DLBCL patients who received CAR T-cell therapy and underwent [18F]FDG PET/CT within 3 months before (pre-infusion) and 1 month after CAR T-cell infusion (M1) were retrospectively reviewed and regularly followed up. Maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), metabolic tumor volume (MTV), clinical indices, and laboratory indicators were recorded at pre-infusion and M1 time points, and changes in these indices were calculated. Progression-free survival (PFS) and overall survival (OS) were as endpoints. Based on the multivariate Cox regression analysis, two predictive models for PFS and OS were developed and evaluated the efficiency. Pre-infusion indices were subjected to predict the grade of cytokine release syndrome (CRS) resulting from toxic reactions.

RESULTS

For survival analysis at a median follow-up time of 18.2 months, patients with values of international prognostic index (IPI), SUVmax at M1, and TLG at M1 above their optimal thresholds had a shorter PFS (median PFS: 8.1 months [IPI ≥ 2] vs. 26.2 months [IPI < 2], P = 0.025; 3.1 months [SUVmax ≥ 5.69] vs. 26.8 months [SUVmax < 5.69], P < 0.001; and 3.1 months [TLG ≥ 23.79] vs. 26.8 months [TLG < 23.79], P < 0.001). In addition, patients with values of SUVmax at M1 and ∆SUVmax% above their optimal thresholds had a shorter OS (median OS: 12.6 months [SUVmax ≥ 15.93] vs. 'not reached' [SUVmax < 15.93], P < 0.001; 32.5 months [∆SUVmax% ≥ -46.76] vs. 'not reached' [∆SUVmax% < -46.76], P = 0.012). Two novel predictive models for PFS and OS were visualized using nomogram. The calibration analysis and the decision curves demonstrated good performance of the models. Spearman's rank correlation (rs) analysis revealed that the CRS grade correlated strongly with the pre-infusion SUVmax (rs = 0.806, P < 0.001) and moderately with the pre-infusion TLG (rs = 0.534, P < 0.001). Multinomial logistic regression analysis revealed that the pre-infusion value of SUVmax correlated with the risk of developing a higher grade of CRS (P < 0.001).

CONCLUSION

In this group of DLBCL patients who underwent CAR T-cell therapy, SUVmax at M1, TLG at M1, and IPI were independent risk factors for PFS, and SUVmax at M1 and ∆SUVmax% for OS. Based on these indicators, two novel predictive models were established and verified the efficiency for evaluating PFS and OS. Moreover, pre-infusion SUVmax correlated with the severity of any subsequent CRS. We conclude that metabolic parameters measured using [18F]FDG PET/CT can identify DLBCL patients who will benefit most from CAR T-cell therapy, and the value before CAR T-cell infusion may predict its toxicity in advance.

The development of a prediction model based on random survival forest for the prognosis of non- Hodgkin lymphoma: A prospective cohort study in China

Background and objective

The pathological staging of non-Hodgkin lymphoma (NHL) is complex, the clinical manifestations are varied, and the prognosis differ considerably. To provide a useful reference for early detection and effective treatment of NHL, we developed a random survival forest (RSF) prognostic model based on machine learning (ML) algorithms using prospective cohort data collected from Chongqing Cancer Hospital from Jan 1, 2017 to Dec 31, 2019 (n = 1449) to compare with the traditional cornerstone method Cox proportional hazards (CPH) model and evaluate the predictability of the model.

Methods

Patients were randomly split into a training cohort (TC) and validation cohort (VC) based on 65/35 ratio. The least absolute shrinkage and selection operator (LASSO) regression analysis was used to extracted the important features. And the RSF was modeled to explore the prognostic factors impacting the overall survival (OS) of patients with NHLs in the TC and validated in the VC. The C-index, the Integrated Brier Score (IBS), Kaplan-Meir method, the receiver operating characteristic (ROC) curve, and the area under the ROC curve (AUC) were selected to measure performances and discriminations of the models. In addition, individual survival probability predicted for NHL patients.

Results

According to the features extracted by LASSO model and univariable Cox model, 16 variables were selected to develop the RSF model with log-rank splitting rule, which were age, ethnicity, medical insurance, Ann Arbor stage, pathology, targeted-therapy, chemo-therapy, peripheral blood neutrophil count to lymphocyte count ratio (NLR), peripheral blood platelet count to lymphocyte count ratio (PLR), serum lactate dehydrogenase (LDH), CD4/CD8, platelet (PLT), absolute neutrophil count (ANC), lymphocyte (LYM), B-symptoms, and (CPR) were important prognostic factors. Compared to the CPH model (C-index = 0.748, IBS = 0.166), the RSF model (C-index = 0.786, IBS = 0.165) is outperformed in predictability and accuracy. The AUC of the RSF model to estimate the 1-, 3-, and 5-year OS in TC were 0.847, 0.847, and 0.809, respectively; while those in the CPH were 0.816, 0.803, and 0.750, respectively.

Conclusions

To provide practical implications for the implementation of individualized therapy, the study constructed a high-performed RSF model and reveal that it outperformed the traditional model CPH. And the RSF model ranked the risk variables. In addition, we stratified the risk of NHL patients and estimated individual survival probability based on the RSF model.

A Review of CAR-T Combination Therapies for Treatment of Gynecological Cancers

CAR-T cell therapy offers a promising way for prolonged cancer remission, specifically in the case of blood cancers. However, its application in the treatment of solid tumors still faces many limitations. This review paper provides a comprehensive overview of the challenges and strategies associated with CAR-T cell therapy for solid tumors, with a focus on gynecological cancer. This study discusses the limitations of CAR-T therapy for solid tumor treatment, such as T cell exhaustion, stromal barrier, and antigen shedding. Additionally, it addresses possible approaches to increase CAR-T efficacy in solid tumors, including combination therapies with checkpoint inhibitors and chemotherapy, as well as the novel approach of combining CAR-T with oncolytic virotherapy. Given the lack of comprehensive research on CAR-T combination therapies for treating gynecological cancers, this review aims to provide insights into the current landscape of combination therapies for solid tumors and highlight the potential of such an approach in gynecology.

Prognostic impact of corticosteroid and tocilizumab use following chimeric antigen receptor T-cell therapy for multiple myeloma

Despite being the mainstay of management for cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), there is limited data regarding the impact of tocilizumab (TCZ) and corticosteroids (CCS) on chimeric antigen receptor (CAR) T-cell efficacy in multiple myeloma (MM). The present study aims to evaluate the prognostic impact of these immunosuppressants in recipients of BCMA- or GPRC5D-directed CAR T cells for relapsed/refractory MM. Our retrospective cohort involved patients treated with commercial or investigational autologous CAR T-cell products at a single institution from March 2017-March 2023. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall response rate (ORR), complete response rate (CRR), and overall survival (OS). In total, 101 patients (91% treated with anti-BCMA CAR T cells and 9% treated with anti-GPRC5D CAR T cells) were analyzed. Within 30 days post-infusion, 34% received CCS and 49% received TCZ for CRS/ICANS management. At a median follow-up of 27.4 months, no significant difference in PFS was observed between CCS and non-CCS groups (log-rank p = 0.35) or between TCZ and non-TCZ groups (log-rank p = 0.69). ORR, CRR, and OS were also comparable between evaluated groups. In our multivariable model, administering CCS with/without TCZ for CRS/ICANS management did not independently influence PFS (HR, 0.74; 95% CI, 0.36-1.51). These findings suggest that, among patients with relapsed/refractory MM, the timely and appropriate use of CCS or TCZ for mitigating immune-mediated toxicities does not appear to impact the antitumor activity and long-term outcomes of CAR T-cell therapy.

Current challenges and therapeutic advances of CAR-T cell therapy for solid tumors

The application of chimeric antigen receptor (CAR) T cells in the management of hematological malignancies has emerged as a noteworthy therapeutic breakthrough. Nevertheless, the utilization and effectiveness of CAR-T cell therapy in solid tumors are still limited primarily because of the absence of tumor-specific target antigen, the existence of immunosuppressive tumor microenvironment, restricted T cell invasion and proliferation, and the occurrence of severe toxicity. This review explored the history of CAR-T and its latest advancements in the management of solid tumors. According to recent studies, optimizing the design of CAR-T cells, implementing logic-gated CAR-T cells and refining the delivery methods of therapeutic agents can all enhance the efficacy of CAR-T cell therapy. Furthermore, combination therapy shows promise as a way to improve the effectiveness of CAR-T cell therapy. At present, numerous clinical trials involving CAR-T cells for solid tumors are actively in progress. In conclusion, CAR-T cell therapy has both potential and challenges when it comes to treating solid tumors. As CAR-T cell therapy continues to evolve, further innovations will be devised to surmount the challenges associated with this treatment modality, ultimately leading to enhanced therapeutic response for patients suffered solid tumors.

Collection efficiency and safety of large-volume leukapheresis for the manufacturing of tisagenlecleucel

BACKGROUND

In patients with relapsed or refractory B cell acute lymphoblastic leukemia or B cell non-Hodgkin lymphoma (r/r B-ALL/B-NHL) with low CD3+ cells in the peripheral blood (PB), sufficient CD3+ cell yield in a single day may not be obtained with normal-volume leukapheresis (NVL). Large-volume leukapheresis (LVL) refers to the processing of more than three times the total blood volume (TBV) in a single session for PB apheresis; however, the efficiency and safety of LVL for manufacturing of tisagenlecleucel (tisa-cel) remain unclear. This study aimed to investigate the tolerability of LVL.

STUDY DESIGN AND METHODS

We retrospectively collected data on LVL (≥3-fold TBV) and NVL (<3-fold TBV) performed for patients with r/r B-ALL/B-NHL in our institution during November 2019 and September 2023. All procedures were performed using a continuous mononuclear cell collection (cMNC) protocol with the Spectra Optia.

RESULTS

Although pre-apheresis CD3+ cells in the PB were significantly lower in LVL procedures (900 vs. 348/μL, p < .01), all patients could obtain sufficient CD3+ cell yield in a single day with a comparably successful rate of final products (including out-of-specification) between the two groups (97.2% vs. 100.0%, p = 1.00). The incidence and severity of citrate toxicity (no patients with grade ≥ 3) during procedures was not significantly different between the two groups (22.2% vs. 26.1%, p = .43) and no patient discontinued leukapheresis due to any complications.

CONCLUSION

LVL procedures using Spectra Optia cMNC protocol was well tolerated and did not affect the manufacturing of tisa-cel.

Chimeric Antigen Receptor T-cell based cellular therapies for cancer: An introduction and Indian perspective

Using one's own immune system for curing cancer has been an active field of research in cancer biology and therapeutics. One such opportunity in cellular immunotherapy is adoptive cell transfers. With the recent approval of CAR-T therapy as a cancer treatment, a whole new paradigm of cancer treatment has opened-up, with a ray of hope for relapsed/refractory cancer patients. Despite promising clinical outcomes, the therapy is in its early phase and remains out of reach for most patients due to its high cost and logistic challenges. In India, these therapies are unavailable and further confounded by the economic challenges and a large population. In this review, we discuss various aspects of T-cell immunotherapies with a special focus on CAR-T in the Indian scenario. We touch upon the basic scientific aspects, mechanism of action, manufacturing, clinical aspects and commercial aspects of the CAR-Tcell therapies and its future worldwide and in India.

Recent advances on CAR-T signaling pave the way for prolonged persistence and new modalities in clinic

Chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the treatment of hematological malignancies. The importance of the receptor costimulatory domain for long-term CAR-T cell engraftment and therapeutic efficacy was demonstrated with second-generation CAR-T cells. Fifth generation CAR-T cells are currently in preclinical trials. At the same time, the processes that orchestrate the activation and differentiation of CAR-T cells into a specific phenotype that predisposes them to long-term persistence are not fully understood. This review highlights ongoing research aimed at elucidating the role of CAR domains and T-cell signaling molecules involved in these processes.

Persistent Cytopenia After CD19 CAR T Therapy in Relapsed/Refractory DLBCL Patients Could Be a Predictor of Efficacy and Side Effects

Hematological toxicity is a severe adverse event (AE) in anti-CD19 chimeric antigen receptor (CAR) T cell therapy for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, the pathophysiological mechanism underlying prolonged cytopenia and the relationship between persistent cytopenia, efficacy, and AEs after anti-CD19 CAR T cell therapy are unknown. Therefore, this study explored whether persistent cytopenia after anti-CD19 CAR T cell therapy in patients with R/R DLBCL can predict therapeutic efficacy and AEs. Thirty-eight patients with R/R DLBCL were enrolled in an anti-CD19 CAR T cell therapy clinical trial. Patients received lymphodepleting chemotherapy with fludarabine and cyclophosphamide before CAR T cell therapy. The degree and duration of cytopenia, clinical response, proportion of CAR T cells, interleukin-6 (IL-6) levels, AEs, and follow-up were observed after therapy. Grades 3-4 persistent cytopenia occurred in 14 patients with R/R DLBCL, who recovered 8-18 weeks after CAR T cell infusion. These patients achieved an objective response rate (ORR) for anti-CD19 CAR T cell therapy. In patients who achieved ORR, the incidence of Grades 3-4 persistent cytopenia was higher in patients with a high tumor load than in those without a high tumor load. The mean peaks of IL-6 and anti-CD19 CAR T cells and the cytokine release syndrome grade in patients with Grades 3-4 persistent cytopenia were higher than those in patients without persistent cytopenia. Anti-CD19 CAR T cells were observed 21 and 28 days after infusion, and patients had Grades 3-4 persistent cytopenia. Progression-free and overall survival were higher in patients with Grades 3-4 persistent cytopenia than in those without cytopenia. Therefore, persistent cytopenia after anti-CD19 CAR T cell therapy in patients with R/R DLBCL can predict therapeutic efficacy and AEs, allowing clinicians to determine the efficiency of CD-19 CAR T cell therapy and the associated AEs.

Low-Frequency PPM1D Gene Mutations Affect Treatment Response to CD19-Targeted CAR T-Cell Therapy in Large B-Cell Lymphoma

Chimeric antigen receptor T (CAR T)-cell therapy has become a standard treatment option for patients with relapsed or refractory diffuse large B-cell lymphoma (r/r DLBCL). Mutations in the PPM1D gene, a frequent driver alteration in clonal hematopoiesis (CH), lead to a gain of function of PPM1D/Wip1 phosphatase, impairing p53-dependent G1 checkpoint and promoting cell proliferation. The presence of PPM1D mutations has been correlated with reduced response to standard chemotherapy in lymphoma patients. In this study, we analyzed the impact of low-frequency PPM1D mutations on the safety and efficacy of CD19-targeted CAR T-cell therapy in a cohort of 85 r/r DLBCL patients. In this cohort, the prevalence of PPM1D gene mutations was 20% with a mean variant allele frequency (VAF) of 0.052 and a median VAF of 0.036. CAR T-induced cytokine release syndrome (CRS) and immune effector cell-associated neuro-toxicities (ICANS) occurred at similar frequencies in patients with and without PPM1D mutations. Clinical outcomes were globally worse in the PPM1D mutated (PPM1Dmut) vs. PPM1D wild type (PPM1Dwt) subset. While the prevalent treatment outcome within the PPM1Dwt subgroup was complete remission (56%), the majority of patients within the PPM1Dmut subgroup had only partial remission (60%). Median progression-free survival (PFS) was 3 vs. 12 months (p = 0.07) and median overall survival (OS) was 5 vs. 37 months (p = 0.004) for the PPM1Dmut and PPM1Dwt cohort, respectively. Our data suggest that the occurrence of PPM1D mutations in the context of CH may predict worse outcomes after CD19-targeted CAR T-cell therapy in patients with r/r DLBCL.

Cost-effectiveness analysis of transplant-ineligible relapsed or refractory diffuse large B-cell lymphoma treatment options-Experience of the efficiency frontier approach

OBJECTIVES

The treatment of relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) changed remarkably since the European Medicines Agency-approved chimeric antigen receptor T-cell (CAR-T) therapies (axicabtagene ciloleucel [axi-cel], lisocabtagene maraleucel [liso-cel], tisagenlecleucel [tisa-cel]) for the third-line onwards (3+L), and targeted therapies (polatuzumab vedotin-bendamustine-rituximab [pola-BR], tafasitamab-lenalidomide [Tafa-L]) for the second-line (2L) onwards. As associated rising treatment costs represent an economic burden, the cost-effectiveness of transplant-ineligible R/R DLBCL interventions was assessed from a German healthcare payer's perspective, using the efficiency frontier (EF) approach.

METHODS

A systematic literature review was performed to determine the clinical benefit concerning median overall survival (OS) of bendamustine-rituximab (BR), rituximab-gemcitabine-oxaliplatin (R-GemOx), axi-cel, liso-cel, tisa-cel, pola-BR, and Tafa-L. First-year treatment costs (drug and medical services costs) were calculated. Results were merged on two-dimensional graphs illustrating 2L and 3+L EFs.

RESULTS

Second-line EF is formed by BR (median OS 11.49 months, €23 958) and Tafa-L (45.7, €104 541), 3+L EF is formed by R-GemOx (12.0, €29 080), Tafa-L (15.5, €104 541), and axi-cel (18.69, €308 516). These interventions build the respective cost-effectiveness thresholds for novel interventions.

CONCLUSIONS

Using the EF approach, the currently most cost-effective interventions (based on cost-effectiveness ratios) in the indication of R/R DLBCL were identified to guide international reimbursement decisions.

Prolonged haematologic toxicity in CAR-T-cell therapy: A review

Chimeric antigen receptor-T-cell (CAR-T-cell) therapy is a novel immunotherapy with encouraging results for treatment of relapsed/refractory haematologic malignancies. With increasing use, our understanding of immune-mediated side effects such as cytokine release syndrome and neurotoxicity has improved; nevertheless, prolonged haematologic toxicity (PHT), with a high incidence rate, remains underrecognized. Owing to heterogeneity in populations, the CAR-T cells used and diseases treated as well as differences in the definition of PHT, its rate, risk factors and management vary across studies. In this review, we provide a narrative of PHT occurring in patients following CAR-T-cell therapy; evidence of PHT treatment strategies is also presented, with the aim of contributing to systematic understanding of PHT.

Impact of SCHOLAR-1 Criteria on Chimeric Antigen Receptor T Cell Therapy Efficacy in Aggressive B Lymphoma: A Real-World GELTAMO/GETH Study

In the pre-chimeric antigen receptor T cell (CAR-T) therapy era, the SCHOLAR-1 study identified a group of patients with refractory aggressive B cell lymphoma (ABCL) with particularly poor prognoses. We recently published our real-world data from Spain, focused on this SCHOLAR-1 refractory group, and compared patients who underwent CAR-T therapy with the previous standard of care. In this study, we found that the efficacy of CAR-T therapy in refractory patients, in terms of progression-free survival (PFS) and overall survival (OS), was superior to that of the treatments available in the pre-CAR-T era. The main objective of these new analyses was to analyze treatment efficacy in terms of response rates and survival for patients with ABCL with or without the SCHOLAR-1 criteria. In addition, we analyzed the prognostic impact of each SCHOLAR-1 criterion independently. Our study aimed to assess the prognostic impact of SCHOLAR-1 criteria on ABCL patients treated with CAR-T therapy in Spain. This multicenter, retrospective, observational study. We included all adult patients treated with commercially available CAR-T cell products and diagnosed with ABCL different from primary mediastinal large B cell lymphoma between February 2019 and July 2022. Patients meeting any SCHOLAR-1 criteria (progressive disease as the best response to any line of therapy, stable disease as the best response to ≥4 cycles of first-line therapy or ≥2 cycles of later-line therapy, or relapse at <12 months after autologous stem cell transplantation [auto-SCT]) in the line of treatment before CAR-T therapy (SCHOLAR-1 group) were compared with those not meeting any of these criteria (non-SCHOLAR-1 group). To analyze the prognostic impact of individual SCHOLAR-1 criteria, all the patients who met any of the SCHOLAR-1 criteria at any time were included to assess whether these criteria have the same prognostic impact in the CAR-T era. In addition, patients were grouped according to whether they were refractory to the first line of treatment, refractory to the last line of treatment, or relapsed early after auto-SCT. The PFS and OS were calculated from the time of appearance of the SCHOLAR-1 refractoriness criteria. Of 329 patients treated with CAR-T (169 with axi-cel and 160 with tisa-cel), 52 were in the non-SCHOLAR-1 group and 277 were in the SCHOLAR-1 group. We found significantly better outcomes in the non-SCHOLAR-1 patients compared with the SCHOLAR-1 patients (median PFS of 12.2 and 3.3 months, respectively; P = .009). In addition, axi-cel showed better results in terms of efficacy than tisa-cel for both the non-SCHOLAR-1 group (hazard ratio [HR] for PFS, 2.7 [95% confidence interval (CI), 1.1 to 6.7; P = .028]; HR for OS, 7.1 [95% CI, 1.5 to 34.6; P = .015]) and SCHOLAR-1 group (HR for PFS, 1.8 [95% CI, 1.3 to 2.5; P < .001]; HR for OS, 1.8 [95% CI, 1.2 to 2.6; P = .002]), but also significantly more toxicity. Finally, separately analyzing the prognostic impact of each SCHOLAR-1 criterion revealed that refractoriness to the last line of treatment was the variable with the most significant impact on survival. In conclusion, SCHOLAR-1 refractoriness criteria notably influence the efficacy of CAR-T therapy. In our experience, axi-cel showed better efficacy than tisa-cel for both SCHOLAR-1 and non-SCHOLAR-1 patients. Refractoriness to the last line of treatment was the variable with the most significant impact on survival in the CAR-T therapy era.

Real-world experience of CAR T-cell therapy in older patients with relapsed/refractory diffuse large B-cell lymphoma

The emergence of chimeric antigen receptor (CAR) T-cell therapy has changed the treatment landscape for diffuse large B-cell lymphoma (DLBCL); however, real-world experience reporting outcomes among older patients treated with CAR T-cell therapy is limited. We leveraged the 100% Medicare fee-for-service claims database and analyzed outcomes and cost associated with CAR T-cell therapy in 551 older patients (aged ≥65 years) with DLBCL who received CAR T-cell therapy between 2018 and 2020. CAR T-cell therapy was used in third line and beyond in 19% of patients aged 65 to 69 years and 22% among those aged 70 to 74 years, compared with 13% of patients aged ≥75 years. Most patients received CAR T-cell therapy in an inpatient setting (83%), with an average length of stay of 21 days. The median event-free survival (EFS) following CAR T-cell therapy was 7.2 months. Patients aged ≥75 years had significantly shorter EFS compared with patients aged 65 to 69 and 70 to 74 years, with 12-month EFS estimates of 34%, 43%, and 52%, respectively (P = .002). The median overall survival was 17.1 months, and there was no significant difference by age groups. The median total health care cost during the 90-day follow-up was $352 572 and was similar across all age groups. CAR T-cell therapy was associated with favorable effectiveness, but the CAR T-cell therapy use in older patients was low, especially in patients aged ≥75 years, and this age group had a lower rate of EFS, which illustrates the unmet need for more accessible, effective, and tolerable therapy in older patients, especially those aged ≥75 years.

Chimeric antigen receptor T-cell therapy yields similar outcomes in patients with and without cytokine release syndrome

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of many patients with aggressive relapsed or refractory large B-cell lymphoma (LBCL). Treatment can be complicated by clinically evident cytokine release syndrome (CRS), which is characterized by the development of fever, hypoxia, and hypotension, and can be life-threatening. Most patients treated with CAR-T cells develop CRS, which is thought to represent an immune phenomenon. It was previously unknown whether patients who did not develop CRS had reduced CAR-T cell activity and were therefore likely to have worse outcomes. We conducted a multicenter retrospective analysis of 352 adult patients treated at 8 academic medical centers in the United States who received axicabtagene ciloleucel or tisagenlecleucel for the treatment of LBCL. The outcomes of interest included progression-free survival, overall survival, complete response rate, and overall response rate. Of the included patients, 262 (74.4%) developed CRS. There was no significant difference in progression-free survival (P = .99) or overall survival (P = .16) between patients who developed CRS and those who did not develop CRS. Peak ferritin levels >5000 ng/mL during treatment and lactate dehydrogenase levels greater than the institutional upper limit of normal before lymphodepleting chemotherapy were associated with significantly worse progression-free and overall survival in the multivariate analysis. There was no significant difference in the complete response or overall response rates between patients who did and did not develop CRS. In this retrospective analysis, we report that patients who develop CRS have clinical outcomes similar to those of patients without CRS treated with commercial anti-CD19 CAR-T cells.

Complexities in comparing the impact of costimulatory domains on approved CD19 CAR functionality

Chimeric antigen receptors (CARs) are engineered to target T cells specifically to tumor cells, resulting in the engineered T cell killing the tumor cell. This technology has been developed to target a range of cancers, with the most notable successes in the treatment of B-cell malignancies where four approved therapies, all targeting CD19, are on the market. These four products differ in the costimulation domains, with axicabtagene ciloleucel (Yescarta) and brexucabtagene autoleucel (Tecartus) both utilizing the CD28 costimulation domain whilst tisagenlecleucel (Kymriah) and lisocabtagene maraleucel (Breyanzi) both utilizing the 4-1BB costimulation domain. There are clearly defined differences in how the CD28 and 4-1BB domains signal, yet it is difficult to ascertain which domain affords a superior mechanism of action given many other differences between these products, including overall CAR architecture and manufacturing methods. Additionally, while in vitro and preclinical in vivo studies have compared CARs with different costimulation domains, it remains a challenge to extrapolate differences observed in this biology across different experimental systems to the overall product performance. While there has been extensive preclinical and clinical work looking at CARs with a variety of targeting domains and architectures, this review will focus on the differences between the four marketed anti-CD19 CAR-Ts, with an additional focus on the impact of hinge and transmembrane domain on CAR activity and interaction with the target cell as well as other proteins on the surface of the T-cell.

A validated composite comorbidity index predicts outcomes of CAR T-cell therapy in patients with diffuse large B-cell lymphoma

Chimeric antigen receptor T-cell therapy (CART) has extended survival of patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL). However, limited durability of response and prevalent toxicities remain problematic. Identifying patients who are at high risk of disease progression, toxicity, and death would inform treatment decisions. Although the cumulative illness rating scale (CIRS) has been shown to correlate with survival in B-cell malignancies, no prognostic score has been independently validated in CART recipients. We retrospectively identified 577 patients with relapsed/refractory DLBCL indicated for CART at 9 academic centers to form a learning cohort (LC). Random survival forest modeling of overall survival (OS) and progression-free survival (PFS) was performed to determine the most influential CIRS organ systems and severity grades. The presence of a severe comorbidity (CIRS score ≥ 3) in the respiratory, upper gastrointestinal, hepatic, or renal system, herein termed "Severe4," had the greatest impact on post-CART survival. Controlling for other prognostic factors (number of prior therapies, Eastern Cooperative Oncology Group performance status, BCL6 translocation, and molecular subtype), Severe4 was strongly associated with shorter PFS and OS in the LC and in an independent single-center validation cohort (VC). Severe4 was also a significant predictor of grade ≥3 cytokine release syndrome in the LC, while maintaining this trend in the VC. Thus, our results indicate that adverse outcomes for patients with DLBCL meant to receive CART can be predicted using a simplified CIRS-derived comorbidity index.

Integrating CAR-T cell therapy into the management of DLBCL: what we are learning

INTRODUCTION

Chimeric Antigen Receptor ;(CAR) T cells therapies have become part of the standard of care for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). The weakness of CAR-T therapies is that there are no comparative clinical trials, although many publications based on real-life data have confirmed the results obtained in pivotal studies. After several years of the commercialization of CAR-T, some points still need to be fully clarified. Healthcare professionals have questions about identifying patients who may benefit from therapy. There are aspects inherent in the accessibility of care related to improved relationships between CAR-T-delivering and referral centers.

AREAS COVERED

Open questions are inherent in the salvage and bridge therapy, predictive criteria for response and persistence of CAR-T after infusion. Managing toxicities remain a top priority and one of the points on which further knowledge is needed.

EXPERT OPINION

This review aims to describe the current landscape of CAR-T cells in DLBCL, outline their outcomes and toxicities, and explain the outstanding questions that remain to be addressed.

The Contemporary Landscape and Future Directions of Intratumoral Immunotherapy

Systemically administered immunotherapies have revolutionized the care of patients with cancer; however, for many cancer types, most patients do not exhibit objective responses. Intratumoral immunotherapy is a burgeoning strategy that is designed to boost the effectiveness of cancer immunotherapies across the spectrum of malignancies. By locally administering immune-activating therapies into the tumor itself, immunosuppressive barriers in the tumor microenvironment can be broken. Moreover, therapies too potent for systemic delivery can be safely administered to target location to maximize efficacy and minimize toxicity. In order for these therapies to be effective, though, they must be effectively delivered into the target tumor lesion. In this review, we summarize the current landscape of intratumoral immunotherapies and highlight key concepts that influence intratumoral delivery, and by extension, efficacy. We also provide an overview of the breadth and depth of approved minimally invasive delivery devices that can be considered to improve delivery of intratumoral therapies.

Cardiac and inflammatory biomarker differences in adverse cardiac events after chimeric antigen receptor T-Cell therapy: an exploratory study

BACKGROUND

Chimeric antigen receptor T- Cell (CAR-T) immunotherapy has been a breakthrough treatment for various hematological malignancies. However, cardiotoxicities such as new-onset heart failure, arrhythmia, acute coronary syndrome and cardiovascular death occur in 10-15% of patients treated with CAR-T. This study aims to investigate the changes in cardiac and inflammatory biomarkers in CAR-T therapy to determine the role of pro-inflammatory cytokines.

METHODS

In this observational study, ninety consecutive patients treated with CAR-T underwent baseline cardiac investigation with electrocardiogram (ECG), transthoracic echocardiogram (TTE), troponin-I, and B-type natriuretic peptide (BNP). Follow-up ECG, troponin-I and BNP were obtained five days post- CAR-T. In a subset of patients (N = 53), serum inflammatory cytokines interleukin (IL)-2, IL-6, IL-15, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, granulocyte-macrophage colony-stimulating factor (GM-CSF), and angiopoietin 1 & 2 were tested serially, including baseline and daily during hospitalization. Adverse cardiac events were defined as new-onset cardiomyopathy/heart failure, acute coronary syndrome, arrhythmia and cardiovascular death.

RESULTS

Eleven patients (12%) had adverse cardiac events (one with new-onset cardiomyopathy and ten with new-onset atrial fibrillation). Adverse cardiac events appear to have occurred among patients with advanced age (77 vs. 66 years; p = 0.002), higher baseline creatinine (0.9 vs. 0.7 mg/dL; 0.007) and higher left atrial volume index (23.9 vs. 16.9mL/m²; p = 0.042). Day 5 BNP levels (125 vs. 63pg/mL; p = 0.019), but not troponin-I, were higher in patients with adverse cardiac events, compared to those without. The maximum levels of IL-6 (3855.0 vs. 254.0 pg/mL; p = 0.021), IFN-γ (474.0 vs. 48.8pg/mL; p = 0.006) and IL-15 (70.2 vs. 39.2pg/mL; p = 0.026) were also higher in the adverse cardiac events group. However, cardiac and inflammatory biomarker levels were not associated with cardiac events. Patients who developed cardiac events did not exhibit worse survival compared to patients without cardiac events (Log-rank p = 0.200).

CONCLUSION

Adverse cardiac events, predominantly atrial fibrillation, occur commonly after CAR-T (12%). The changes in serial inflammatory cytokine after CAR-T in the setting of adverse cardiac events suggests pro-inflammation as a pathophysiology and require further investigation for their role in adverse cardiac events.

TWEET BRIEF HANDLE

CAR-T related Cardiotoxicity has elevated cardiac and inflammatory biomarkers. #CARTCell #CardioOnc #CardioImmunology.

Therapeutic efficacy and infectious complications of CD19-targeted chimeric antigen receptor-modified T cell immunotherapy

Lymphocyte depletion chemotherapy CD19-targeted chimeric antigen receptor-modified T (CAR-T) cell immunotherapy is an innovative approach for the treatment of refractory or relapsed B-cell malignancies. This method also has the occurrence of infection, and there has been no systematic analysis of infectious complications. In our study, we intend to analyze the infection in patients between day 0 and day 90 by analyzing the data of 40 patients who received CD19 CAR-T cell therapy collected in our hospital. We assessed risk factors for infection before and after treatment using Poisson and Cox regression, respectively. A cohort study was used, including patients with acute lymphocytic leukemia, chronic lymphocytic leukemia and non-Hodgkin's lymphoma. 40 patients were infected for the first time occurred at a median of 6 days after CAR-T cell infusion, and 8 (20%) had 10 infections within 28 days after CAR-T cell infusion, on days 29 and 29. The infection density between 90 days was lower at 0.67. This resulted in an infection density of 1.19 infections per 100 days. Two patients (5%) developed invasive fungal infections and two patients (5%) developed life-threatening or fatal infections. In an adjusted model for baseline characteristics, patients with ALL, ≥4 prior antitumor regimens, and receiving the highest CAR-T cell dose had higher infection densities at 28 days. The incidence of infection was comparable to that observed in clinical trials of salvage associated with infection after CAR-T cell infusion.

How I treat refractory/relapsed diffuse large B-cell lymphomas with CD19-directed chimeric antigen receptor T cells

Chimeric antigen receptor (CAR) T cells targeting CD19 represent a promising salvage immunotherapy for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL), offering ~40% of long-term responses. In everyday clinical practice, haematologists involved in CAR T cell treatment of patients with R/R DLBCL have to deal with diagnostically complex cases and difficult therapeutic choices. The availability of novel immunotherapeutic agents for R/R DLBCL and recent advances in understanding CAR T-cell failure mechanisms demand a rational approach to identify the best choice for bridging therapy and managing post-CAR T-cell therapy relapses. Moreover, positron emission tomography/computerised tomography may result in false-positive interpretation, highlighting the importance of post-treatment biopsy. In this review, we discuss all above issues, presenting four instructive cases, with the aim to provide criteria and new perspectives for CAR T-cell treatment of DLBCL.

CAR T-Cells for the Treatment of Refractory or Relapsed Large B-Cell Lymphoma: A Single-Center Retrospective Canadian Study

BACKGROUND

Chimeric antigen receptor (CAR) T-cells are an important new third-line treatment option for large B-cell lymphoma (LBCL). The objective response rates in pivotal early phase clinical trials with CAR T-cells were very promising. The objective of this study was to describe the efficacy results obtained with CAR T-cells infusions in our institution and to compare the toxicities of our cohort with those of pivotal trials and studies conducted in a real-life setting.

PATIENTS AND METHODS

Efficacy and safety data were retrospectively collected from 25 patients with LBCL treated with CAR T-cells therapy at CHU de Québec-Université Laval. A literature search was then performed to identify other efficacy or safety data from a real-life setting.

RESULTS

At 3 months post infusion, the objective response rate (ORR) in our population with tisagenlecleucel and axicabtagene-ciloleucel were 20% and 47%, respectively. Bulky disease was the only negative predictor of poor response at 3 months (0% vs. 53%, P = .03). Bulky disease was associated with a median PFS of 2 months compared to 5 months for non-bulky disease (P = .0009). Grade ≥ 3 hematological toxicities were greater in patients treated with axi-cel (60% vs. 20%, P = .048), without bone marrow involvement (55% vs. 0%, P =.046), without stage IV disease (72% vs. 21%, P =.02), with refractory disease (67% vs. 10%, P =.01) or having been affected by cytokine release syndrome (58% vs. 0%, P =.02).

CONCLUSION

The poor response rate at 3 months after infusion in our cohort was influenced mainly by bulky disease. Further studies are needed to better characterize the loss of efficacy of CAR T-cells because the majority of patients will relapse over time.

Efficacy and safety of relmacabtagene autoleucel, an anti-CD19 chimeric antigen receptor T cell, in relapsed/refractory B-cell non-Hodgkin's lymphoma: 2-year results of a phase 1 trial

This study reported 2-year efficacy and safety of relma-cel in Chinese patients with relapsed/refractory (R/R) B-cell non-Hodgkin's lymphoma (B-NHL). In this phase 1 dose-escalating trial, patients received lymphodepleting chemotherapy for 3 days, followed by relma-cel as a single infusion in escalating dose levels (25 × 10⁶, 50 × 10⁶, 100 × 10⁶, and 150 × 10⁶ CAR-T cells). The endpoints included best objective response rate (ORR), best complete response rate (CRR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. A total of 23 patients were enrolled, including 60.9% with diffuse large B-cell lymphoma and 26.1% with follicular lymphoma. Twenty patients were evaluable for efficacy, and the best ORR was 85.0% and the best CRR was 75.0%. With a median follow-up of 24.2 months, 6 patients died and 2 had progressive disease, the median DOR, PFS, and OS were all not reached. The 2-year PFS and OS rates were 60.0% and 70.0%, respectively. Any grade and grade ≥ 2 cytokine release syndrome occurred in 18.2% and 13.6% of patients, respectively. Only 1(4.5%) patient had grade 3 CRS lasting 13 days, which was resolved by tocilizumab. No grade ≥ 2 neurotoxicity events or treatment-related deaths occurred. Patients with R/R B-NHL treated with relma-cel achieved durable response with favorable safety profile.

Predictors and Management of Relapse to Axicabtagene Ciloleucel in Patients with Aggressive B-cell Lymphoma

OBJECTIVE/BACKGROUND

Despite the success of chimeric antigen receptor (CAR) T-cell therapy in patients with aggressive non-Hodgkin lymphoma (aNHL), some patients still fail treatment, and their prognosis is dismal.

METHODS

We performed a retrospective study of aNHL patients treated with axicabtagene ciloleucel (axi-cel) at two Mayo Clinic centers between 2018 and 2020. We evaluated predictive factors, toxicities, and responses to salvage regimens after CAR T-cell therapy.

RESULTS

Thirty-four patients received axi-cel with a median length of hospitalization of 14 days. Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome of any grade occurred in 91% and 41% of patients, respectively. Furthermore, 71% of patients responded to therapy, with 53% achieving a complete response (CR). The CRS grade and absolute lymphocyte count at leukapheresis (ALC_Leuk) correlated with CR and overall survival (OS), respectively. After a median follow-up of 6.8 months (interquartile range [IQR] 4.6-14.9), 15 patients (44%) showed progressive disease (PD). Most patients (60%) progressed during the first 3 months and had persistent CD19 tumor expression. Elevated C-reactive protein at baseline increased the risk of PD, whereas elevated ferritin increased PD and mortality risk. Twelve patients received salvage therapy, but only three responded. Median OS of relapsed/refractory patients to axi-cel was 3 months (IQR 1.3-5.1).

CONCLUSION

The grade of CRS and ALC_Leuk correlated with better outcomes to axi-cel therapy. In addition, elevated inflammatory markers at baseline were associated with PD and shorter survival. Relapses after treatment frequently occur within months after axi-cel infusion; they confer a poor prognosis and create an urgent need for novel and effective treatment options in this patient population.

CD4 CAR-T cells targeting CD19 play a key role in exacerbating cytokine release syndrome, while maintaining long-term responses

BACKGROUND

To date, T cells redirected with CD19-specific chimeric antigen receptors (CAR) have gained impressive success in B-cell malignancies. However, treatment failures are common and the occurrence of severe toxicities, such as cytokine release syndrome (CRS), still limits the full exploitation of this approach. Therefore, the development of cell products with improved therapeutic indexes is highly demanded.

METHODS

In this project, we investigated how CD4 and CD8 populations cooperate during CD19 CAR-T cell responses and what is their specific role in CRS development. To this aim, we took advantage of immunodeficient mice reconstituted with a human immune system (HuSGM3) and engrafted with the B-cell acute lymphoblastic leukemia cell line NALM-6, a model that allows to thoroughly study efficacy and toxicity profiles of CD19 CAR-T cell products.

RESULTS

CD4 CAR-T cells showed superior proliferation and activation potential, which translated into stronger stimulation of myeloid cells, the main triggers of adverse events. Accordingly, toxicity assessment in HuSGM3 mice identified CD4 CAR-T cells as key contributors to CRS development, revealing a safer profile when they harbor CARs embedded with 4-1BB, rather than CD28. By comparing differentially co-stimulated CD4:CD8 1:1 CAR-T cell formulations, we observed that CD4 cells shape the overall expansion kinetics of the infused product and are crucial for maintaining long-term responses. Interestingly, the combination of CD4.BBz with CD8.28z CAR-T cells resulted in the lowest toxicity, without impacting antitumor efficacy.

CONCLUSIONS

Taken together, these data point out that the rational design of improved adoptive T-cell therapies should consider the biological features of CD4 CAR-T cells, which emerged as crucial for maintaining long-term responses but also endowed by a higher toxic potential.

Combining chemotherapy with CAR-T cell therapy in treating solid tumors

Chemotherapy has long been a standard treatment for a wide range of malignancies, where patients typically undergo multiple rounds of chemotherapy regimens to control tumor growth. In the clinic, the chemotherapy drugs cyclophosphamide and fludarabine are commonly used prior to Chimeric Antigen Receptor T (CAR-T) cell therapy to lymphodeplete and improve CAR-T cell engraftment. In this review, we discuss the use of chemotherapy in combination with CAR-T cell therapy. We also show that chemotherapy can deplete immunosuppressive cells, promote a pro-inflammatory tumor microenvironment, disrupt tumor stroma, and improve CAR-T cell recruitment to the tumor. Although the combination of chemotherapy plus CAR-T cell therapy is promising, certain aspects of chemotherapy also pose a challenge. In addition, the combined therapeutic effect may be heavily dependent on the dose and the treatment schedule. Thus, we also discussed the obstacles to effective clinical outcomes of the combination therapy.

Clinical and Radiographic Predictors of Progression and Survival in Relapsed/Refractory Lymphoma Patients Receiving Anti-CD19 CAR T-cell Therapy

INTRODUCTION

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized treatment of relapsed/refractory (R/R) B-cell lymphomas, though certain patients do not respond to treatment or relapse afterwards. The purpose of this study is to determine patient variables that are predictive of response to CAR-T therapy.

METHODS

We conducted a retrospective review of 59 R/R B-cell non-Hodgkin lymphoma patients who received anti-CD19 CAR T-cell therapy. Risk factors for progression free survival (PFS) and overall survival (OS) were identified and multivariate logistic regression models for PFS and OS at 1 year were created using stepwise selection. The final multivariate logistic regression models were used to estimate the area under the receiver operating curve (AUROC).

RESULTS

At median follow up of 25.6 months, median overall survival was not reached, and median progression free survival was 5.7 months. Stage IV disease (odds ratio (OR) 9.335, P = .025) was identified as a predictive variable for progression at day 365 with an AUC of 0.7922 (P < .001). IPI (OR 2.828, P = .014), ALC ≥ 0.50 at collection (OR 0.183, P = .043), CRP ≥ 11 (OR 6.177, P = .019), and tocilizumab administration (OR 0.062, P = .005) as predictors for death at day 365 with an AUC 0.8626 (P < .001).

CONCLUSION

Clinical variables identify R/R lymphoma patients who are at risk for progression and poor overall survival after CAR T-cell therapy. IPI, CRP, ALC, and tocilizumab administration may be predictors of survival.

Dose-response correlation for CAR-T cells: a systematic review of clinical studies

The potential of chimeric antigen receptor (CAR) T cells to successfully treat hematological cancers is widely recognized. Multiple CAR-T cell therapies are currently under clinical development, with most in early stage, during which dose selection is a key goal. The objective of this review is to address the question of dose-dependent effects on response and/or toxicity from available CAR-T cell clinical trial data. For that purpose, systematic literature review of studies published between January 2010 and May 2022 was performed on PubMed and Embase to search clinical studies that evaluated CAR-T cells for hematological cancers. Studies published in English were considered. Studies in children (age <18 years), solid tumors, bispecific CAR-T cells and CAR-T cell cocktails were excluded. As a result, a total of 74 studies met the inclusion criteria. Thirty-nine studies tested multiple dose levels of CAR-T cells with at least >1 patient at each dose level. Thirteen studies observed dose-related increase in disease response and 23 studies observed dose-related increase in toxicity across a median of three dose levels. Optimal clinical efficacy was seen at doses 50-100 million cells for anti-CD19 CAR-T cells and >100 million cells for anti-BCMA CAR-T cells in majority of studies. The findings suggest, for a given construct, there exists a dose at which a threshold of optimal efficacy occurs. Dose escalation may reveal increasing objective response rates (ORRs) until that threshold is reached. However, when ORR starts to plateau despite increasing dose, further dose escalation is unlikely to result in improved ORR but is likely to result in higher incidence and/or severity of mechanistically related adverse events.

Health economic analysis of third-line interventions in diffuse large B-cell lymphomas in Germany: applying the efficiency frontier

BACKGROUND

In the past decades, highly innovative treatments in the field of diffuse large B-cell lymphoma (DLBCL) became available in clinical practice. The aim of this study was to assess the cost-benefit relation of third-line interventions in DLBCL from a German payer perspective.

METHODS

Clinical benefit of allogeneic stem cell transplantation (alloSCT), chimeric antigen receptor T cells therapy (CAR T) [tisagenlecleucel (tisa-cel) and axicabtagene ciloleucel (axi-cel)] and best supportive care (BSC) was assessed in terms of median overall survival (median OS) derived from a systematic literature review in PubMed. Real-world treatment costs were retrieved from the university hospitals Cologne and Hamburg-Eppendorf. The cost-benefit relation was analysed using the efficiency frontier concept.

RESULTS

Median OS varied from 6.3 months in BSC to 23.5 months in CAR T (axi-cel), while median real-world treatment costs ranged likewise widely from €26,918 in BSC to €340,458 in CAR T (axi-cel). Shown by the efficiency frontier, alloSCT and axi-cel were found as most efficient interventions.

CONCLUSION

The efficiency frontier supports the pricing of innovative therapies, such as third-line interventions in DLBCL, in relation to appropriate comparators. Yet, studies with longer follow-up periods are needed to include studies with unreached median OS and to reflect experiences gained with CAR T in clinical practice.

Current Status of Novel Agents for the Treatment of B Cell Malignancies: What's Coming Next?

Resistance to death is one of the hallmarks of human B cell malignancies and often contributes to the lack of a lasting response to today's commonly used treatments. Drug discovery approaches designed to activate the death machinery have generated a large number of inhibitors of anti-apoptotic proteins from the B-cell lymphoma/leukemia 2 family and the B-cell receptor (BCR) signaling pathway. Orally administered small-molecule inhibitors of Bcl-2 protein and BCR partners (e.g., Bruton's tyrosine kinase and phosphatidylinositol-3 kinase) have already been included (as monotherapies or combination therapies) in the standard of care for selected B cell malignancies. Agonistic monoclonal antibodies and their derivatives (antibody-drug conjugates, antibody-radioisotope conjugates, bispecific T cell engagers, and chimeric antigen receptor-modified T cells) targeting tumor-associated antigens (TAAs, such as CD19, CD20, CD22, and CD38) are indicated for treatment (as monotherapies or combination therapies) of patients with B cell tumors. However, given that some patients are either refractory to current therapies or relapse after treatment, novel therapeutic strategies are needed. Here, we review current strategies for managing B cell malignancies, with a focus on the ongoing clinical development of more effective, selective drugs targeting these molecules, as well as other TAAs and signaling proteins. The observed impact of metabolic reprogramming on B cell pathophysiology highlights the promise of targeting metabolic checkpoints in the treatment of these disorders.

Point-of-care CAR T-cell therapy as salvage strategy for out-of-specification tisagenlecleucel

Tisagenlecleucel (tisa-cel) is an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for patients with relapsed/refractory large B-cell lymphoma. Outcomes of patients with out-of-commercial specification (OOS) CAR T products are not well characterized. We therefore assessed 37 adult patients who underwent leukapheresis for tisa-cel therapy in a single center. In nine (24%) patients, manufactured tisa-cel was considered OOS. Three of them (33%) received tisa-cel after institutional review board approval; 2/9 (22%) did not receive tisa-cel due to disease progression; and 4/9 (44%) received academic point-of-care (POC) CAR T-cell as salvage therapy, at a median of 35 days following OOS notification. Three of those four patients achieved a complete response. In univariate analysis, risk factors for OOS were ≥ 4 prior therapies or previous bendamustine exposure. In conclusion, we report high OOS incidence of 24% in real-life setting. Forty-four percent of those patients received POC CAR T-cell as salvage therapy.

Cytopenias following anti-CD19 chimeric antigen receptor (CAR) T cell therapy: a systematic analysis for contributing factors

BACKGROUND

Cytopenia is one of the most common adverse events following the CAR-T cell infusion, affecting the quality of life and potentially leading to life-threatening bleeding and infection. This study aimed to systematically review the cytopenias following anti-CD19 CAR-T therapy and further analyse the contributing factors.

METHODS

Databases including PubMed, MEDLINE, Embase and Cochrane were systematically searched on 8 May 2022. A random-effect meta-analysis was used to estimate the incidence of cytopenia, and subgroup analyses were applied to explore heterogeneity.

RESULTS

A total of 68 studies involving 2950 patients were included in this study. The overall incidence of all grade anaemia, thrombocytopenia, neutropenia, leukopoenia, lymphocytopenia and febrile neutropenia was 65%, 55%, 78%, 62%, 70% and 27%, respectively, and the corresponding cytopenias of grade 3 or worse were 33%, 31%, 61%, 45%, 46%, and 21%, respectively. Subgroup analysis showed increased incidence of cytopenias in subgroups with lower median age, proportion of males (<65%) and proportion of bridging therapy (<80%) and in the subgroup with a median line of prior therapy ≥3. In terms of disease and therapeutic target, cytopenias were more frequent in ALL patients and in dual-target CAR-T therapies (targeting CD19 in combination with other targets). Furthermore, CAR-T products manufactured by lentiviral vectors and those with the costimulatory domain of CD28 were more likely to cause haematological toxicity. No significant differences were observed in cytopenia between patients treated with CAR-T products with murine and humanized scFv.

CONCLUSION

In conclusion, neutropenia is the most frequent cytopenia after CAR-T therapy, both in all grades or grade ≥3. The incidence of cytopenias following CAR-T therapy is influenced by the age, sex, disease and number of prior therapy lines of the patients, as well as the target and costimulatory domain of CAR-T cells, and viral vectors used for manufacturing.KEY MESSAGESNeutropenia is the most frequent cytopenia after CAR-T therapy.The clinical characteristics of the patients, the design of CAR-T cells and the protocol of CAR-T treatment can influence the occurrence of cytopenias following the CAR-T therapy.

A real-world comparison of tisagenlecleucel and axicabtagene ciloleucel CAR T cells in relapsed or refractory diffuse large B cell lymphoma

Axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) have both demonstrated impressive clinical activity in relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). In this study, we analyzed the outcome of 809 patients with R/R DLBCL after two or more previous lines of treatment who had a commercial chimeric antigen receptor (CAR) T cells order for axi-cel or tisa-cel and were registered in the retrospective French DESCAR-T registry study ( NCT04328298 ). After 1:1 propensity score matching (n = 418), the best overall response rate/complete response rate (ORR/CRR) was 80%/60% versus 66%/42% for patients treated with axi-cel compared to tisa-cel, respectively (P < 0.001 for both ORR and CRR comparisons). After a median follow-up of 11.7 months, the 1-year progression-free survival was 46.6% for axi-cel and 33.2% for tisa-cel (hazard ratio (HR) = 0.61; 95% confidence interval (CI), 0.46-0.79; P = 0.0003). Overall survival (OS) was also significantly improved after axi-cel infusion compared to after tisa-cel infusion (1-year OS 63.5% versus 48.8%; HR = 0.63; 95% CI, 0.45-0.88; P = 0.0072). Similar findings were observed using the inverse probability of treatment weighting statistical approach. Grade 1-2 cytokine release syndrome was significantly more frequent with axi-cel than with tisa-cel, but no significant difference was observed for grade ≥3. Regarding immune effector cell-associated neurotoxicity syndrome (ICANS), both grade 1-2 and grade ≥3 ICANS were significantly more frequent with axi-cel than with tisa-cel. In conclusion, our matched comparison study supports a higher efficacy and also a higher toxicity of axi-cel compared to tisa-cel in the third or more treatment line for R/R DLBCL.

Targeting CD19 in diffuse large B-cell lymphoma: An expert opinion paper

The ubiquitous, early-stage expression, efficient internalization, limited off-target effects, and high disease specificity of CD19 make it an attractive therapeutic target. Currently available anti-CD19 therapies have demonstrated particular promise in patients with relapsed or refractory B-cell non-Hodgkin lymphoma. Selection of the most appropriate treatment strategy should be based on individual patient characteristics and the goal of therapy. However, evidence and knowledge about the sequencing of anti-CD19 therapies are limited. Here, we review the current evidence for CD19 as a target in diffuse large B-cell lymphoma and consider approaches to the use of anti-CD19 therapy.

Transplant-ineligible but chimeric antigen receptor T-cells eligible: a real and relevant population

Autologous stem cell transplantation (ASCT) and chimeric antigen receptor (CAR) T-cells are two therapeutic options for relapsed/refractory diffuse large B-cell lymphoma. Both are intensive and potentially curative therapies but differ in their efficacy and toxicity. ASCT may be offered to 'fit' patients (i.e. usually young with limited comorbidities) with chemosensitive disease. On the other hand, real world studies have shown that CAR T-cells may be safely administered to less fit and older patients. Thus, there is a potentially significant population of patients who may be offered CAR T-cell therapy despite not being eligible for ASCT. As the relative role of ASCT and CAR T-cells evolves, recognising and defining this population may be increasingly relevant. Here, we review criteria which may help identify this 'ASCT-ineligible but CAR T-cells eligible' population of patients.

Hematologic cytopenia post CAR T cell therapy: Etiology, potential mechanisms and perspective

Chimeric Antigen-Receptor (CAR) T-cell therapies have shown dramatic efficacy in treating relapsed and refractory cancers, especially B cell malignancies. However, these innovative therapies cause adverse toxicities that limit the broad application in clinical settings. Hematologic cytopenias, one frequently reported adverse event following CAR T cell treatment, are manifested as a disorder of hematopoiesis with decreased number of mature blood cells and subdivided into anemia, thrombocytopenia, leukopenia, and neutropenia, which increase the risk of infections, fatigue, bleeding, fever, and even fatality. Herein, we initially summarized the symptoms, etiology, risk factors and management of cytopenias. Further, we elaborated the cellular and molecular mechanisms underlying the initiation and progression of cytopenias following CAR T cell therapy based on previous studies about acquired cytopenias. Overall, this review will facilitate our understanding of the etiology of cytopenias and shed lights into developing new therapies against CAR T cell-induced cytopenias.

Co-Stimulatory Receptor Signaling in CAR-T Cells

T cell engineering strategies have emerged as successful immunotherapeutic approaches for the treatment of human cancer. Chimeric Antigen Receptor T (CAR-T) cell therapy represents a prominent synthetic biology approach to re-direct the specificity of a patient's autologous T cells toward a desired tumor antigen. CAR-T therapy is currently FDA approved for the treatment of hematological malignancies, including subsets of B cell lymphoma, acute lymphoblastic leukemia (ALL) and multiple myeloma. Mechanistically, CAR-mediated recognition of a tumor antigen results in propagation of T cell activation signals, including a co-stimulatory signal, resulting in CAR-T cell activation, proliferation, evasion of apoptosis, and acquisition of effector functions. The importance of including a co-stimulatory domain in CARs was recognized following limited success of early iteration CAR-T cell designs lacking co-stimulation. Today, all CAR-T cells in clinical use contain either a CD28 or 4-1BB co-stimulatory domain. Preclinical investigations are exploring utility of including additional co-stimulatory molecules such as ICOS, OX40 and CD27 or various combinations of multiple co-stimulatory domains. Clinical and preclinical evidence implicates the co-stimulatory signal in several aspects of CAR-T cell therapy including response kinetics, persistence and durability, and toxicity profiles each of which impact the safety and anti-tumor efficacy of this immunotherapy. Herein we provide an overview of CAR-T cell co-stimulation by the prototypical receptors and discuss current and emerging strategies to modulate co-stimulatory signals to enhance CAR-T cell function.

Clinical Strategies for Enhancing the Efficacy of CAR T-Cell Therapy for Hematological Malignancies

Chimeric antigen receptor (CAR) T cells have been successfully used for hematological malignancies, especially for relapsed/refractory B-cell acute lymphoblastic leukemia and non-Hodgkin’s lymphoma. Patients who have undergone conventional chemo-immunotherapy and have relapsed can achieve complete remission for several months with the infusion of CAR T-cells. However, side effects and short duration of response are still major barriers to further CAR T-cell therapy. To improve the efficacy, multiple targets, the discovery of new target antigens, and CAR T-cell optimization have been extensively studied. Nevertheless, the fact that the determination of the efficacy of CAR T-cell therapy is inseparable from the discussion of clinical application strategies has rarely been discussed. In this review, we will discuss some clinical application strategies, including lymphodepletion regimens, dosing strategies, combination treatment, and side effect management, which are closely related to augmenting and maximizing the efficacy of CAR T-cell therapy.

Bendamustine is safe and effective for lymphodepletion before tisagenlecleucel in patients with refractory or relapsed large B-cell lymphomas

BACKGROUND

Anti-CD19 chimeric antigen receptor T-cell immunotherapy (CAR-T) is now a standard treatment of relapsed or refractory B-cell non-Hodgkin lymphomas; however, a significant portion of patients do not respond to CAR-T and/or experience toxicities. Lymphodepleting chemotherapy is a critical component of CAR-T that enhances CAR-T-cell engraftment, expansion, cytotoxicity, and persistence. We hypothesized that the lymphodepletion regimen might affect the safety and efficacy of CAR-T.

PATIENTS AND METHODS

We compared the safety and efficacy of lymphodepletion using either fludarabine/cyclophosphamide (n = 42) or bendamustine (n = 90) before tisagenlecleucel in two cohorts of patients with relapsed or refractory large B-cell lymphomas treated consecutively at three academic institutions in the United States (University of Pennsylvania, n = 90; Oregon Health & Science University, n = 35) and Europe (University of Vienna, n = 7). Response was assessed using the Lugano 2014 criteria and toxicities were assessed by the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and, when possible, the American Society for Transplantation and Cellular Therapy (ASTCT) consensus grading.

RESULTS

Fludarabine/cyclophosphamide led to more profound lymphocytopenia after tisagenlecleucel infusion compared with bendamustine, although the efficacy of tisagenlecleucel was similar between the two groups. We observed significant differences, however, in the frequency and severity of adverse events. In particular, patients treated with bendamustine had lower rates of cytokine release syndrome and neurotoxicity. In addition, higher rates of hematological toxicities were observed in patients receiving fludarabine/cyclophosphamide. Bendamustine-treated patients had higher nadir neutrophil counts, hemoglobin levels, and platelet counts, as well as a shorter time to blood count recovery, and received fewer platelet and red cell transfusions. Fewer episodes of infection, neutropenic fever, and post-infusion hospitalization were observed in the bendamustine cohort compared with patients receiving fludarabine/cyclophosphamide.

CONCLUSIONS

Bendamustine for lymphodepletion before tisagenlecleucel has efficacy similar to fludarabine/cyclophosphamide with reduced toxicities, including cytokine release syndrome, neurotoxicity, infectious and hematological toxicities, as well as reduced hospital utilization.

Impact of glucocorticoids on short-term and long-term outcomes in patients with relapsed/refractory multiple myeloma treated with CAR-T therapy

Background

Glucocorticoids (GCs) are often used to treat cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). The effects of GCs on the efficacy of CAR-T cell treatment in relapsed/refractory multiple myeloma (RRMM) have not been fully established. We evaluated the impact of GCs on clinical outcomes of RRMM patients treated with CAR-T cells.

Methods

This study involved RRMM patients treated with CAR-T cells at our center between June 2017 and December 2020. Patients were stratified into GC-used group (GC-group) and non-GC-used group (NGC-group). CRS or ICANS was graded on the basis of the American Society of Transplantation and Cellular Therapy consensus grading system. Response status was evaluated by the IMWG Uniform Response Criteria. The duration of response (DOR), progression-free survival (PFS), and overall survival (OS) were calculated.

Result

A total of 71 patients were included in this study. In the NGC group (40 patients), 34 (85%) had responses to CAR-T cell therapy, including 16 (40%) stringent complete response (sCR), seven (17.5%) complete response (CR), five (12.5%) very good partial response (VGPR), and six (15%) partial response (PR). The overall response rate (ORR) and complete response rate (CRR) in the NGC group were 85% and 57.5%. In the GC group (31 patients), 29 (93.5%) had responses, including 11 (35.5%) sCR, nine (29%) CR, two (6.4%) VGPR, and seven (22.6%) PR. Differences in ORR and CRR between the two groups were insignificant. The dose, duration, and timing of GCs did not affect ORR and CRR. At a median follow-up of 28.2 months, the median PFS was 20.4 months (95% CI, 7.9 to 32.9) while the median OS was 36.6 months (95% CI, 25.9 to 47.2) for the GC group. The median PFS and OS for the NGC group were 13.7 months (95% CI, 8.8 to 18.6) and 27.5 months (95% CI, 14.1 to 41.0). There were no significant differences in either PFS or OS between the GC group and the NGC group. Differences in median DOR for the patients with CR or better in the GC group and NGC group were not significant (p = 0.17). Earlier, prolonged use and high dose of GCs were not associated with any effects on either PFS or OS. Additionally, GCs had no effects on CAR-T cell proliferation.

Conclusion

Administration of GCs, dose, timing, and duration does not influence the clinical efficacy of CAR-T cells in RRMM in this study.

CAR T-Based Therapies in Lymphoma: A Review of Current Practice and Perspectives

While more than half of non-Hodgkin lymphomas (NHL) can be cured with modern frontline chemoimmunotherapy regimens, outcomes of relapsed and/or refractory (r/r) disease in subsequent lines remain poor, particularly if considered ineligible for hematopoietic stem cell transplantation. Hence, r/r NHLs represent a population with a high unmet medical need. This therapeutic gap has been partially filled by adoptive immunotherapy. CD19-directed autologous chimeric antigen receptor (auto-CAR) T cells have been transformative in the treatment of patients with r/r B cell malignancies. Remarkable response rates and prolonged remissions have been achieved in this setting, leading to regulatory approval from the U.S. Food and Drug Administration (FDA) of four CAR T cell products between 2017 and 2021. This unprecedented success has created considerable enthusiasm worldwide, and autologous CAR T cells are now being moved into earlier lines of therapy in large B cell lymphoma. Herein, we summarize the current practice and the latest progress of CD19 auto-CAR T cell therapy and the management of specific toxicities and discuss the place of allogeneic CAR T development in this setting.

Advances in immune therapies in hematological malignancies

Immunotherapy in cancer takes advantage of the exquisite specificity, potency, and flexibility of the immune system to eliminate alien tumor cells. It involves strategies to activate the entire immune defense, by unlocking mechanisms developed by tumor cells to escape from surrounding immune cells, as well as engineered antibody and cellular therapies. What is important to note is that these are therapeutics with curative potential. The earliest example of immune therapy is allogeneic stem cell transplantation, introduced in 1957, which is still an important modality in hematology, most notably in myeloid malignancies. In this review, we discuss developmental trends of immunotherapy in hematological malignancies, focusing on some of the strategies that we believe will have the most impact on future clinical practice in this field. In particular, we delineate novel developments for therapies that have already been introduced into the clinic, such as immune checkpoint inhibition and chimeric antigen receptor T-cell therapies. Finally, we discuss the therapeutic potential of emerging strategies based on T-cell receptors and adoptive transfer of allogeneic natural killer cells.