Allogeneic Transplant and CAR-T Therapy After Autologous Transplant Failure in DLBCL: A Noncomparative Cohort Analysis

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2024 update on the diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an aggressive B-cell lymphoma associated with EBV infection included in the WHO classification of lymphoid neoplasms since 2016. Although historically associated to poor prognosis, outcomes seem to have improved in the era of chemoimmunotherapy.

DIAGNOSIS

The diagnosis is established through meticulous pathological evaluation. Detection of EBV-encoded RNA (EBER) is the standard diagnostic method. The ICC 2022 specifies EBV+ DLBCL, NOS as occurring when >80% of malignant cells express EBER, whereas the WHO-HAEM5 emphasizes that the majority of tumor cells should be EBER positive without setting a defined threshold. The differential diagnosis includes plasmablastic lymphoma, DLBCL associated with chronic inflammation, primary effusion lymphoma, among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. Therefore, inclusion of patients in clinical trials when available is recommended. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

Chimeric antigen receptor T-cell infusion for large B-cell lymphoma in complete remission: a center for international blood and marrow transplant research analysis

CD19 CAR T-cell (CAR-T) therapy is commonly administered to patients with relapsed or refractory large B-cell lymphomas (LBCL), but salvage or bridging therapy can sometimes lead to a complete response (CR) prior to infusion. Limited studies have assessed the outcomes of patients infused in CR. A total of 134 patients with LBCL in CR prior to CAR-T infusion were identified from the CIBMTR registry, with median prior lines of therapy of 3 (range 2-9). At two years post-infusion, the probability of progression-free survival was 43.5% (95% CI 34.4-52.8) and the probability of overall survival was 63.8% (95% CI 54.4-72.6). The cumulative incidence rates of non-relapse mortality and relapse/progression at two years were 9.2% (95% CI 4.5-15.4) and 47.3% (95% CI 38.2-56.6), respectively. The rate of grade 3 or higher cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were 2.2% and 8.2%, respectively. In summary, CAR-T in heavily pretreated patients with LBCL who are in CR following two or more lines of prior therapy demonstrate that a subset of patients may remain free of progression at two years. Additionally, the toxicity profile was impressive with very low rates of grade 3 CRS and ICANS.

Adoptive cellular therapy after hematopoietic stem cell transplantation

Effective cellular therapy using CD19 chimeric antigen receptor T-cells for the treatment of advanced B-cell malignancies raises the question of whether the administration of adoptive cellular therapy (ACT) posttransplant could reduce relapse and improve survival. Moreover, several early phase clinical studies have shown the potential beneficial effects of administration of tumor-associated antigen-specific T-cells and natural killer cells posttransplant for high-risk patients, aiming to decrease relapse and possibly improve survival. In this article, we present an in-depth review of ACT after transplantation, which has the potential to significantly improve the efficacy of this procedure and revolutionize this field.

Outcomes of allogeneic hematopoietic stem cell transplantation for relapsed or refractory diffuse large B-cell lymphoma

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a currative treatment modality for diffuse large B-cell lymphoma (DLBCL) because of the intrinsic graft-versus-lymphoma effect. However, limited information is available regarding which patients with relapsed or refractory DLBCL are likely to benefit from allo-HSCT. We retrospectively analyzed data from 1268 DLBCL patients who received allo-HSCT. The overall survival and progression-free survival (PFS) rates were 30.3% and 21.6% at 3 years, respectively. Multivariate analysis revealed that stable or progressive disease at transplantation, male patient, poorer performance status at transplantation, and shorter intervals from previous transplantation were associated independently with a lower PFS. Four prognostic factors were used to construct a prognostic index for PFS, predicting 3-year PFS of 55.4%, 43.7%, 20.4% and 6.6%, respectively. The prognostic model predicted relapse rates following allo-HSCT accordingly (P < 0.0001), whereas did not predict transplantation-related mortality (P = 0.249). The prognostic index can identify a subgroup of DLBCL patients who benefit from allo-HSCT and it is worthwhile to evaluate whether this model is also applicable to patients undergoing allo-HSCT in cases of relapse after chimeric antigen receptor engineered T-cell therapy, although the application of allo-HSCT has been declining with the increase of novel immunotherapies.

Genetic and transcriptomic analyses of diffuse large B-cell lymphoma patients with poor outcomes within two years of diagnosis

Despite the improvements in clinical outcomes for DLBCL, a significant proportion of patients still face challenges with refractory/relapsed (R/R) disease after receiving first-line R-CHOP treatment. To further elucidate the underlying mechanism of R/R disease and to develop methods for identifying patients at risk of early disease progression, we integrated clinical, genetic and transcriptomic data derived from 2805 R-CHOP-treated patients from seven independent cohorts. Among these, 887 patients exhibited R/R disease within two years (poor outcome), and 1918 patients remained in remission at two years (good outcome). Our analysis identified four preferentially mutated genes (TP53, MYD88, SPEN, MYC) in the untreated (diagnostic) tumor samples from patients with poor outcomes. Furthermore, transcriptomic analysis revealed a distinct gene expression pattern linked to poor outcomes, affecting pathways involved in cell adhesion/migration, T-cell activation/regulation, PI3K, and NF-κB signaling. Moreover, we developed and validated a 24-gene expression score as an independent prognostic predictor for treatment outcomes. This score also demonstrated efficacy in further stratifying high-risk patients when integrated with existing genetic or cell-of-origin subtypes, including the unclassified cases in these models. Finally, based on these findings, we developed an online analysis tool ( https://lymphprog.serve.scilifelab.se/app/lymphprog ) that can be used for prognostic prediction for DLBCL patients.

A paradox of choice: Sequencing therapy in relapsed/refractory diffuse large B-cell lymphoma

The available treatments for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) have experienced a dramatic change since 2017. Incremental advances in basic and translational science over several decades have led to innovations in immune-oncology. These innovations have culminated in eight separate approvals by the US Food and Drug Administration for the treatment of patients with R/R DLBCL over the last 10 years. High-dose therapy and autologous stem cell transplant (HDT-ASCT) remains the standard of care for transplant-eligible patients who relapse after an initial remission. For transplant-ineligible patients or for those who relapse following HDT-ASCT, multiple options exist. Monoclonal antibodies targeting CD19, antibody-drug conjugates, bispecific antibodies, immune effector cell products, and other agents with novel mechanisms of action are now available for patients with R/R DLBCL. There is increasing use of chimeric antigen receptor (CAR) T-cells as second-line therapy for patients with early relapse of DLBCL or those who are refractory to initial chemoimmunotherapy. The clinical benefits of these strategies vary and are influenced by patient and disease characteristics, as well as the type of prior therapy administered. Therefore, there are multiple clinical scenarios that clinicians might encounter when treating R/R DLBCL. An optimal sequence of drugs has not been established, and there is no evidence-based consensus on how to best order these agents. This abundance of choices introduces a paradox: proliferating treatment options are initially a boon to patients and providers, but as choices grow further they no longer liberate. Rather, more choices make the management of R/R DLBCL more challenging due to lack of direct comparisons among agents and a desire to maximize patient outcomes. Here, we provide a review of recently-approved second- and subsequent-line agents, summarize real-world data detailing the use of these medicines, and provide a framework for sequencing therapy in R/R DLBCL.

Allogeneic hematopoietic stem cell transplantation for B-cell lymphoma in Taiwan

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is considered for patients with high-risk B-cell lymphoma and relapsed or refractory disease. This study aimed to analyze the long-term follow-up data of patients who underwent allo-HSCT in Taiwan. This was a retrospective observational study using data from the Taiwan Society of Blood and Marrow Transplantation database. A total of 105 patients who underwent allo-HSCT because of high-risk, relapsed, or refractory disease between 2010 and 2019 were included. Forty-five percent of the patients previously underwent autologous stem cell transplantation (ASCT). The median follow-up duration was 18.6 months. The probability of 3-year progression-free survival and overall survival (OS) was 34.5% and 37%, respectively. The probability of 1-year non-relapse mortality was 31.4%, and the major cause was infection (75.8%). The multivariable analysis showed that not in remission at the time of transplantation and the absence of graft-versus-host disease (GVHD) were factors associated with inferior OS. The probability of 3-year OS in patients with diffuse large B-cell lymphoma who underwent allo-HSCT and allo-HSCT after ASCT was 40.2% and 25.2%, respectively. Allo-HSCT could be a salvage therapeutic option for relapsed or refractory B-cell lymphoma. Complete remission at the time of allo-HSCT and the presence of GVHD are independent variables for overall survival.

CAR-T Cell Therapy in Large B Cell Lymphoma

Large B-cell lymphomas (LBCLs) are among the most frequent (about 30%) non-Hodgkin's lymphoma. Despite the aggressive behavior of these lymphomas, more than 60% of patients can be cured with first-line chemoimmunotherapy using the R-CHOP regimen. Patients with refractory or relapsing disease show a poor outcome even when treated with second-line therapies. CD19-targeted chimeric antigen receptor (CAR) T-cells are emerging as an efficacious second-line treatment strategy for patients with LBCL. Three CD19-CAR-T-cell products received FDA and EMA approval. CAR-T cell therapy has also been explored for treating high-risk LBCL patients in the first-line setting and for patients with central nervous system involvement. Although CD19-CAR-T therapy has transformed the care of refractory/relapsed LBCL, about 60% of these patients will ultimately progress or relapse following CD19-CAR-T; therefore, it is fundamental to identify predictive criteria of response to CAR-T therapy and to develop salvage therapies for patients relapsing after CD19-CAR-T therapies. Moreover, ongoing clinical trials evaluate bispecific CAR-T cells targeting both CD19 and CD20 or CD19 and CD22 as a tool to improve the therapeutic efficacy and reduce the number of refractory/relapsing patients.

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

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

The progress of novel strategies on immune-based therapy in relapsed or refractory diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) can be cured with standard front-line immunochemotherapy, whereas nearly 30-40% of patients experience refractory or relapse. For several decades, the standard treatment strategy for fit relapsed/refractory (R/R) DLBCL patients has been high-dose chemotherapy followed by autologous hematopoietic stem cell transplant (auto-SCT). However, the patients who failed in salvage treatment or those ineligible for subsequent auto-SCT have dismal outcomes. Several immune-based therapies have been developed, including monoclonal antibodies, antibody-drug conjugates, bispecific T-cell engaging antibodies, chimeric antigen receptor T-cells, immune checkpoint inhibitors, and novel small molecules. Meanwhile, allogeneic SCT and radiotherapy are still necessary for disease control for fit patients with certain conditions. In this review, to expand clinical treatment options, we summarize the recent progress of immune-related therapies and prospect the future indirections in patients with R/R DLBCL.

Regeneration of T cells from human-induced pluripotent stem cells for CAR-T cell medicated immunotherapy

Background: Chimeric antigen receptor (CAR) T cell treatment involves in vitro production of T cells from patient blood with synthetic receptors specific to a cancer antigen. They circumvent the major histocompatibility complex to recognize the tumor antigen, reducing hematologic malignancy remission rates by 80%. Considering the efficacy of CAR-T treatment, the present work aimed at generating functional clusters of differentiation (CD)8 + T cells from human induced pluripotent stem cells (hiPSC) and to generate hiPS-CAR-T cells with high antigen-specific cytotoxicity. Methods: The Alkaline phosphatase assay and MycoEasy rapid mycoplasma detection kit was implemented for detection of hiPSCs and mycoplasma, respectively. The CD34⁺ HSPCs were harvested in AggreWellTM 400 using a 37-micron reversible strainer. Likewise, the lymphoid progenitor and CD4⁺CD8⁺ DP T cells were also harvested. The Cell Counting Kit-8 (CCK-8) assay was used to mark cytotoxicity and ELISA was used to detect IFN-γ secretion. Further, flow cytometry and transwell chambers were used to assess cell cycle, and migration and invasion. Finally, the in vivo antitumor effects of the CAR-T cells were evaluated using experimental animals (mice). Results: Results revealed that a serum-free, feeder layer-free differentiation system significantly yielded hiPSC-based T cell immunotherapy with interleukin-2, interleukin-15, and activators at the differentiation stage to promote the maturation of these cells into human induced pluripotent stem (hiPS)-T cells. The infection of hiPSCs with the CD19 CAR lentivirus resulted in the production of the hiPSC-CAR-T cells. We validated the function of hiPS-CAR-T cells in vivo and in vitro experimentation which revealed no significant differences in cell morphology and function between hiPSC-derived hiPS-CAR-T cells and peripheral blood-derived CAR-T cells. Conclusion: This study developed a culture method that is efficient and clinically useful to make functional CD8⁺ T cells from hiPSC and to get hiPS-CAR-T cells with high antigen-specific cytotoxicity that are not very different from CAR T cells found in peripheral blood. As a result, our findings may open the way for the clinical use of hiPSC to create functional CD8⁺ T and hiPS-CAR-T cells cells for use in cell-based cancer therapy.

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.

Role of allogeneic hematopoietic cell transplant for relapsed/refractory aggressive B-cell lymphomas in the CART era

Anti-CD19 chimeric antigen receptor T cells (CART) has rapidly been adopted as the standard third-line therapy to treat aggressive B-cell lymphomas (ABCL) after failure of second-line therapy despite the lack of direct comparisons with allogeneic hematopoietic cell transplantation (alloHCT)-based strategies. Using the Grupo Español de Trasplante y Terapia Celular (GETH-TC) registry, we selected patients with the following characteristics: CART or alloHCT performed between 2016 and 2021; ≥18 years old; ABCL diagnosis; ≥2 lines of therapy; and either anti-CD19 CART or alloHCT as therapy at relapse. The analysis included a total of 316 (CART = 215, alloHCT = 101) patients. Median follow-up was 15 and 36 months for the CART and alloHCT cohorts, respectively. In the multivariate analysis, CART was confirmed to be similar to alloHCT for the primary study endpoint (progression-free survival) (hazard ratio [HR] 0.92, CI95%:0.56-1.51, p = 0.75). Furthermore, when the analysis was limited to only patients with chemo-sensitive diseases (complete and partial response) at infusion (CART = 26, alloHCT=93), no differences were reported (progression-free survival at month +18: 65% versus 55%, p = 0.59). However, CART had lower non-relapse mortality (HR 0.34, 95% CI: 0.13-0.85, p = 0.02). Given the lower toxicity and similar survival outcomes, these results suggest the use of CART before alloHCT.

Relapsed or refractory large B-cell lymphoma after chimeric antigen receptor T-cell therapy: Current challenges and therapeutic options

Chimeric antigen receptor (CAR) T-cell (CAR-T) therapy can provide durable remission in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) after failure of chemoimmunotherapy. However, patients who are refractory or relapsing after CAR-T therapy have poor outcomes. Multiple mechanisms of CAR-T therapy failure have been proposed but management of these patients remains a challenge. As CAR-T therapy moves earlier in the treatment of DLBCL, we urgently need trials focused on patients with relapse after CAR-T therapy. Recent advances in novel immunotherapies such as bispecific antibodies, antibody-drug conjugates and next-generation CAR-T therapies may provide avenues for treatment. Here we review the available data on using these drugs after failure of CAR-T therapy and provide a framework for the ideal sequencing of these novel agents.

Do CAR-T and Allogeneic Stem Cell Transplant Both Have a Place in Lymphoid Neoplasms?

Allogeneic stem cell transplantation (allo-SCT) represented the first immunotherapy to treat hematologic malignancies: it has been considered as a cure for the disease and never as an approach to extend the life of patients. The success of allo-SCT derives both from the ability to treat patients with intensive chemoradiotherapy and from the potent graft-versus-leukemia effects mediated by donor immunity. Although considerable progress has been made in the last years, significant barriers still remain in the form of disease relapse, graft-versus-host disease, infectious complications, and regimen-related toxicities. Moreover, the treatment of hematologic malignancies, particularly acute lymphoblastic leukemia and certain forms of lymphomas, has been revolutionized by the commercial introduction of genetically modified autologous T-lymphocyte therapy (CAR-T). Our review discusses current standards and the shifting paradigms in the indications for allo-SCT and the role of CAR-T cell therapy for lymphoid neoplasms.

Allogeneic transplant following CAR T-cell therapy for large B-cell lymphoma

Allogeneic hematopoietic cell transplantation (alloHCT) can potentially salvage large B-cell lymphoma (LBCL) patients experiencing treatment failure after chimeric antigen receptor T-cell therapy (CAR T). Nonetheless, data on the efficacy and toxicities of alloHCT after receipt of CAR T are limited. We report a multicenter retrospective study assessing the safety, toxicities, and outcomes of alloHCT in LBCL patients following CAR T failure. Eighty-eight patients with relapsed, refractory LBCL received an alloHCT following anti-CD19 CAR T failure. The median number of lines of therapy between CAR T infusion and alloHCT was one (range, 0-7). Low intensity conditioning was used in 77% (n=68) and peripheral blood was the most common graft source (86%, n=76). The most common donor types were matched unrelated donor (39%), followed by haploidentical (30%) and matched related donor (26%). Median follow-up of survivors was 15 months (range, 1-72). One-year overall survival, progression-free survival, and graft-versus-host disease-free relapse-free survival were 59%, 45%, and 39% respectively. One-year non-relapse mortality and progression/relapse were 22% and 33% respectively. On multivariate analysis, <2 lines of intervening therapy between CAR T and alloHCT and complete response at time of alloHCT were associated with better outcomes. In conclusion, alloHCT after CAR T failure can provide durable remissions in a subset of patients.

The place of allogeneic stem cell transplantation in aggressive B-cell non-Hodgkin lymphoma in the era of CAR-T-cell therapy

Chimeric antigen receptor T (CAR-T) cells are a treatment option for patients with relapse/refractory (R/R) non-Hodgkin lymphoma (NHL), acute lymphoid leukemia and multiple myeloma. To date, diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), follicular lymphoma (FL), and chronic lymphocytic leukemia (CLL) have been successfully treated with CAR-T cells directed against the CD19 antigen. However, when R/R disease persists after several treatment lines, patients with these diseases are often referred to transplantation centres to receive allogeneic stem cell transplantation (ALLO-SCT). ALLO-SCT and CAR-T cells share mechanism of actions, inducing immune effects of T-cells (and other cells after transplantation) against lymphoma cells, but they differ in several other characteristics. These differences justify unique positioning of each therapy within treatment algorithms. In this paper, we analyzed the results obtained after ALLO-SCT and CAR-T-cell therapy in patients with aggressive lymphomas (large B-cell lymphoma and MCL) to identify the ideal scenarios in which these 2 immunological therapies should be employed.

Outcomes after allogeneic hematopoietic stem cell transplantation for adults with primary mediastinal B cell lymphoma: a SFGM-TC and LYSA study

Background: Despite therapeutic progress, 10 to 30% of adult patients with primary mediastinal B cell lymphoma (PMBCL) are primary refractory or experience early relapse (R/R). Allogeneic stem cell transplantation (allo-HSCT) thus remains a potentially curative option in this setting.Material and Methods: In this multicenter retrospective study, the outcomes of 33 French and Belgian adult patients allo-transplanted for R/R PMBCL between January 1999 and December 2018, were examined.Results: At allo-HSCT time, patients had received a median of 3 treatment lines, 50% of them were in complete response, 40% in partial response and 10% had a progressive disease. Forty-two percent of the donors were siblings and 39% matched related. The median follow-up for alive patients was 78 months (3.5-157). Considering the whole cohort, 2-year overall survival (OS), progression free survival (PFS) and graft-versus-host disease-free/relapse-free survival (GRFS) were 48% (95%CI: 33-70), 47% (95%CI: 33-68) and 38.5% (95%CI: 25-60) respectively. Cumulative incidence of relapse and non-relapse mortality rates were respectively 34% (95%CI: 18-50) and 18% (95%CI: 7-34). Disease status at transplant was the only factor predicting survivals, patients with progressive disease showing significant lower 2-year PFS (HR: 6.12, 95%CI: 1.32-28.31, p = 0.02) and OS (HR: 7.04, 95%CI: 1.52-32.75, p = 0.013). A plateau was observed for OS and PFS after 4 years with 10 patients alive after this date, suggesting that almost one third of the patients effectively salvaged and undergoing allo-SCT could be cured.Conclusion: This study indicates that allo-HSCT is a valid therapeutic option for R/R PMBCL, providing durable remissions.

Role of CD19 Chimeric Antigen Receptor T Cells in Second-Line Large B Cell Lymphoma: Lessons from Phase 3 Trials. An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy

Since 2017, 3 CD19-directed chimeric antigen receptor (CAR) T cell therapies-axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel-have been approved for relapsed/refractory aggressive diffuse large B cell lymphoma after 2 lines of therapy. Recently, 3 prospective phase 3 randomized clinical trials were conducted to define the optimal second-line treatment by comparing each of the CAR T cell products to the current standard of care: ZUMA-7 for axicabtagene ciloleucel, BELINDA for tisagenlecleucel, and TRANSFORM for lisocabtagene maraleucel. These 3 studies, although largely addressing the same question, had different outcomes, with ZUMA-7 and TRANSFORM demonstrating significant improvement with CD19 CAR T cells in second-line therapy compared with standard of care but BELINDA not showing any benefit. The US Food and Drug Administration has now approved axicabtagene ciloleucel and lisocabtagene maraleucel for LBCL that is refractory to first-line chemoimmunotherapy or relapse occurring within 12 months of first-line chemoimmunotherapy. Following the reporting of these practice changing studies, here a group of experts convened by the American Society for Transplantation and Cellular Therapy provides a comprehensive review of the 3 studies, emphasizing potential differences, and shares perspectives on what these results mean to clinical practice in this new era of treatment of B cell lymphomas.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2022 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an entity included in the WHO classification of lymphoid neoplasms since 2016. EBV+ DLBCL, NOS, is an aggressive B-cell lymphoma associated with EBV infection, and a poor prognosis with standard chemotherapeutic approaches.

DIAGNOSIS

The diagnosis is made through a careful pathological evaluation. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for percentage of positive cells has not been defined. The differential diagnosis includes plasmablastic lymphoma (PBL), DLBCL associated with chronic inflammation, primary effusion lymphoma (PEL), among others.

RISK-STRATIFICATION

The International Prognostic Index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 and PD-1/PD-L1 are emerging as potential adverse but targetable biomarkers.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, might have a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. Therefore, the inclusion of patients in clinical trials when available is recommended. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

Hematopoietic stem cell boost for persistent neutropenia after CAR T-cell therapy: a GLA/DRST study

Hematotoxicity after chimeric antigen receptor (CAR) T-cell therapy is associated with infection and death but management remains unclear. We report results of 31 patients receiving hematopoietic stem cell boost (HSCB; 30 autologous, 1 allogeneic) for either sustained severe neutropenia of grade 4 (<0.5 × 109/L), sustained moderate neutropenia (≤1.5 × 109/L) and high risk of infection, or neutrophil count ≤2.0 × 109/L and active infection. Median time from CAR T-cell therapy to HSCB was 43 days and median absolute neutrophil count at time of HSCB was 0.2. Median duration of neutropenia before HSCB was 38 days (range, 7-151). Overall neutrophil response rate (recovery or improvement) was observed in 26 patients (84%) within a median of 9 days (95% confidence interval, 7-14). Time to response was significantly associated with the duration of prior neutropenia (P = .007). All nonresponders died within the first year after HSCB. One-year overall survival for all patients was 59% and significantly different for neutropenia (≤38 days; 85%) vs neutropenia >38 days before HSCB (44%; P = .029). In conclusion, early or prophylactic HSCB showed quick response and improved outcomes for sustained moderate to severe neutropenia after CAR-T.

Custom CARs: Leveraging the Adaptability of Allogeneic CAR Therapies to Address Current Challenges in Relapsed/Refractory DLBCL

Cellular therapies have transformed the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL), which typically does not respond well to salvage chemotherapy. Recently, approximately 40% of r/r DLBCL patients across three different trials achieved a complete remission at 1 year after receiving treatment with autologous chimeric antigen receptor (CAR) T cells (auto-CARs). These successes have prompted studies of auto-CARs in second-line settings, in which axicabtagene ciloleucel and lisocabtagene maraleucel both showed improved event-free survival over autologous hematopoietic cell transplantation (AHCT). While encouraging, this data also highlights that 60% of patients relapse or progress following treatment with auto-CARs. Individual disease characteristics and logistical challenges of cell engineering also limit patients’ eligibility for auto-CARs. Allogeneic CAR T cells (allo-CARs) may address some of these limitations as they may mitigate delays associated with auto-CARs, thereby reducing the need for bridging chemotherapies and increasing availability of cellular products for patients with aggressive lymphomas. By being sourced from healthy donors who have never been exposed to cytotoxic chemotherapy, allo-CARs can be created from T cells with better fitness. Allo-CARs made from specific cellular subsets (e.g., stem cell memory or naïve/early memory T cells) may also have increased efficacy and long-term persistence. Additionally, allo-CARs have been successfully created from other cell types, including natural killer cells, gamma-delta T-cells and induced pluripotent stem cells. These cell types can be engineered to target viral antigens, enabling precision targeting of virally driven DLBCL. As allogeneic donor cells can be banked and cryopreserved in batches, they can be made more readily available, potentially reducing logistical hurdles and costs compared to engineering auto-CARs. This may ultimately create a more sustainable platform for cell therapies. Challenges with allo-CARs that will need to be addressed include graft versus host disease, alloimmunization, potentially decreased persistence relative to auto-CARs, and antigen escape. In short, the adaptability of allo-CARs makes them ideal for treating patients with r/r DLBCL who have progressed through standard chemotherapy, AHCT, or auto-CARs. Here, we review the published literature on patients with r/r DLBCL treated with allogeneic CAR products manufactured from various cell types as well as forthcoming allogeneic CAR technologies.

Real-World Treatment Patterns After CD19-Directed CAR T Cell Therapy Among Patients with Diffuse Large B Cell Lymphoma

Introduction

CD19-directed chimeric antigen receptor T cells (CAR T) are approved for treatment of adults with relapsed/refractory diffuse large B cell lymphoma (DLBCL) following at least two lines of therapy.

Methods

This study describes real-world treatment patterns after CAR T in adults with DLBCL. It includes adults diagnosed with DLBCL in IBM MarketScan Commercial and Medicare Supplemental healthcare claims databases administered CAR T between 2017 and 2019 (index event) and at least 6 months of continuous health plan enrollment pre-index. Kaplan-Meier methods were used to estimate risk and time to first subsequent treatment after CAR T, as a proxy for CAR T failure.

Results

Among 129 patients meeting study criteria, most (123; 95.4%) were hospitalized during CAR T therapy. Median length of stay was 17 (25th–75th percentile, 13–22) days. Estimated 6-month risk of subsequent treatment was 36.2% (95% confidence interval [CI] 27.1–45.8%). During median follow-up of 195 (25th–75th percentile, 102–362) days, median time to the first line of therapy after CAR T, accounting for censoring, was 378 days (95% CI 226, not reached). Among 48 patients who received another therapy after CAR T, 58.3% received immunotherapy, 50.0% radiation therapy, 25.0% chemotherapy, 25.0% targeted therapy, and 12.5% hematopoietic stem cell transplant.

Conclusions

Among real-world patients with DLBCL treated with CAR T, the risk of not achieving a durable response is considerable; additional, effective options for DLBCL salvage treatment are needed.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02087-4.