Polatuzumab vedotin as a salvage and bridging treatment in relapsed or refractory large B-cell lymphomas

Defining primary refractory large B-cell lymphoma

ABSTRACT

Patients with large B-cell lymphoma (LBCL) that fail to achieve a complete response (CR) or who relapse early after anthracycline-containing immunochemotherapy (IC) have a poor prognosis and are commonly considered to have "primary refractory disease." However, different definitions of primary refractory disease are used in the literature and clinical practice. In this study, we examined variation in the time to relapse used to define refractory status and association with survival outcomes in patients with primary refractory LBCL in a single-center prospective cohort with validation in an independent multicenter cohort. Patients with newly diagnosed LBCL were enrolled in the Molecular Epidemiological Resource cohort (MER; N = 949) or the Lymphoma Epidemiology of Outcomes cohort (LEO; N = 2755) from September 2002 to May 2021. Primary refractory LBCL was defined as no response (stable disease [SD]) or progressive disease (PD) during, or by the end of, frontline (1L) IC (primary PD; PPD); partial response at end of treatment (EOT PR); or relapse within 3 to 12 months after achieving CR at EOT to 1L IC (early relapse). In the MER cohort, patients with PPD had inferior overall survival (OS; 2-year OS rate: 15% MER, 31% LEO) when compared with other subgroups considered in defining primary refractory disease, EOT PR (2-year OS rate: 38% MER, 50% LEO) and early relapse (2-year OS rate: 44% MER, 58% LEO). Among patients receiving 1L IC with curative intent, we identified that patients with PPD are the key subgroup with poor outcomes. We propose a definition of primary refractory LBCL as SD or PD during, or by the end of, 1L treatment.

SOHO State of the Art Updates and Next Questions Updates on Building Your CAR-T Cell Program

Chimeric antigen receptor T-cell (CAR-T) therapy has significantly impacted treatment algorithms and clinical outcomes for a variety of patients with hematologic malignancies over the past decade. The field of cellular immunotherapy is currently experiencing a rapid expansion of the number of patients eligible for CAR-T therapies as approvals are being seen in earlier lines of therapy. With the expanded patients eligible for these therapies, more treatment centers will be necessary to keep up with demand. Building a cellular therapy program can be a daunting task, and therefore, we present our experience with building a clinical cellular therapy program.

Treatment Outcomes with Standard of Care in Relapsed/Refractory Diffuse Large B-Cell Lymphoma: Real-World Data Analysis

INTRODUCTION

Despite new therapies for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL), treatments with chemotherapy, single-agent rituximab/obinutuzumab, single-agent lenalidomide, or combinations of these agents continue to be commonly used.

METHODS

This retrospective study utilized longitudinal data from 4226 real-world electronic health records to characterize outcomes in patients with R/R DLBCL. Eligible patients were diagnosed with DLBCL between January 2010 and March 2022 and had R/R disease treated with ≥ 1 prior systemic line of therapy (LOT), including ≥ 1 anti-CD20-containing regimen.

RESULTS

A total of 573 patients treated with ≥ 1 prior LOT were included (31.2% and 13.4% with ≥ 2 and ≥ 3 prior LOTs, respectively). Median duration of follow-up was 7.7 months. Most patients (57.1%) were male; mean standard deviation (SD) age was 63 (14.7) years. Overall and complete response rates (95% confidence interval (CI) were 52% (48-56) and 23% (19-27). Median duration of response and duration of complete response were 3.5 and 18.4 months. Median progression-free and overall survival (95% CI) was 3.0 (2.8-3.3) and 12.9 (10.1-16.9) months, respectively. Patients with a higher number of prior LOTs, primary refractoriness, refractoriness to last LOT, refractoriness to last anti-CD20-containing regimen, and prior CAR T exposure had worse outcomes (i.e., challenging-to-treat R/R DLBCL) compared with those without these characteristics.

CONCLUSIONS

Outcomes in patients with R/R DLBCL treated with chemotherapy, single-agent rituximab/obinutuzumab, single-agent lenalidomide, or combinations of these agents remain poor, especially for those with challenging-to-treat R/R DLBCL. These findings underscore the unmet need for new, safe, and effective therapies, especially for challenging-to-treat R/R DLBCL populations.

Polatuzumab vedotin plus rituximab and lenalidomide in patients with relapsed or refractory diffuse large B-cell lymphoma: a cohort of a multicentre, single-arm, phase 1b/2 study

BACKGROUND

Diffuse large B-cell lymphoma comprises nearly 30% of non-Hodgkin lymphoma cases and patients with relapsed or refractory diffuse large B-cell lymphoma who are ineligible for stem-cell transplantation have few treatment options and poor prognoses. We aimed to determine whether the novel combination of polatuzumab vedotin in combination with rituximab and lenalidomide (Pola+R+Len) would provide a tolerable treatment option with enhanced antitumour response in patients with relapsed or refractory diffuse large B-cell lymphoma.

METHODS

This completed phase 1b/2, open-label, multicentre, single-arm study (GO29834) evaluated the safety and efficacy of Pola+R+Len in patients with relapsed or refractory diffuse large B-cell lymphoma at 19 sites in three countries (USA, Spain, and UK). Patients (≥18 years old) were eligible for inclusion if they had histologically documented CD20-positive relapsed or refractory diffuse large B-cell lymphoma and Eastern Cooperative Oncology Group performance status of 2 or lower, had received at least one previous line of chemoimmunotherapy, including an anti-CD20 agent, and were ineligible for stem-cell transplantation. The dose-escalation phase (1b) used escalating doses of lenalidomide to find the recommended phase 2 dose. Patients received six 28-day cycles of induction treatment with intravenous rituximab 375 mg/m2 and intravenous polatuzumab vedotin 1·8 mg/kg (all cohorts) plus oral lenalidomide at the following doses: 10 mg (cohort A); 15 mg (cohort B); and 20 mg (cohort C). Rituximab and polatuzumab vedotin were administered on day 1 and lenalidomide on days 1-21 of each 28-day cycle. During the dose-expansion phase (2), patients received six 28-day cycles of Pola+R+Len at the recommended phase 2 dose established during dose escalation. In both phases, patients with a complete response or partial response at the end of induction were eligible for post-induction therapy with rituximab 375 mg/m2 on day 1 and lenalidomide 10 mg/day on days 1-21 of each 28-day cycle for a maximum of 6 cycles. The primary safety objective of the dose-escalation phase was identification of the maximum tolerated dose through incidence of dose-limiting toxic effects. The primary efficacy outcome of the dose-expansion phase was Independent Review Committee-assessed complete response rate at end of induction, based on PET-CT. Analyses were conducted in the safety population, which included all patients who received at least one dose of any study drug, and the efficacy population, which included all patients who received at least one dose of any study drug at the recommended phase 2 dose. This study is registered with ClinicalTrials.gov, number NCT02600897.

FINDINGS

Between July 11, 2017 and Feb 3, 2020, 57 patients were enrolled (median age 71 years [IQR 60-75]; 38 [67%] were male and 19 (33%) were female; 47 [82%] were not Hispanic or Latino; and the median previous lines of therapy was 2 [IQR 1-3]). 18 participants were included in phase 1b and 39 were included in phase 2. Phase 1b confirmed a 20 mg recommended phase 2 dose for lenalidomide. After a median follow-up of 11·8 months (IQR 4·7-25·8), the complete response rate, as assessed by the Independent Review Committee, was 31% (90% CI 20-43). The most common grade 3-4 adverse events were neutropenia (35 [61%] of 57) and thrombocytopenia (eight [14%] of 57). Serious adverse events were reported in 23 (40%) of 57 patients and one patient died due to a treatment-related adverse event (neutropenic sepsis).

INTERPRETATION

Although the combination of Pola+R+Len did not meet the prespecified activity threshold, some patients derived clinical benefit and the regimen had a tolerable safety profile in patients with relapsed or refractory diffuse large B-cell lymphoma.

FUNDING

Genentech/F Hoffmann-La Roche.

Reprogramming natural killer cells for cancer therapy

The last decade has seen rapid development in the field of cellular immunotherapy, particularly in regard to chimeric antigen receptor (CAR)-modified T cells. However, challenges, such as severe treatment-related toxicities and inconsistent quality of autologous products, have hindered the broader use of CAR-T cell therapy, highlighting the need to explore alternative immune cells for cancer targeting. In this regard, natural killer (NK) cells have been extensively studied in cellular immunotherapy and were found to exert cytotoxic effects without being restricted by human leukocyte antigen and have a lower risk of causing graft-versus-host disease; making them favorable for the development of readily available "off-the-shelf" products. Clinical trials utilizing unedited NK cells or reprogrammed NK cells have shown early signs of their effectiveness against tumors. However, limitations, including limited in vivo persistence and expansion potential, remained. To enhance the antitumor function of NK cells, advanced gene-editing technologies and combination approaches have been explored. In this review, we summarize current clinical trials of antitumor NK cell therapy, provide an overview of innovative strategies for reprogramming NK cells, which include improvements in persistence, cytotoxicity, trafficking and the ability to counteract the immunosuppressive tumor microenvironment, and also discuss some potential combination therapies.

Incorporating radiation with anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory non-Hodgkin lymphoma: A multicenter consensus approach

Anti-CD19 chimeric antigen receptor T-cell therapy (CART) has revolutionized the outcomes of relapsed and/or refractory B-cell non-Hodgkin lymphoma. However, CART is still limited by its availability, toxicity, and response durability. Not all patients make it to the CART infusion phase due to disease progression. Among those who receive CART, a significant number of patients experience life-threatening cytokine release syndrome toxicity, and less than half maintain a durable response with the majority relapsing in pre-existing sites of disease present pre-CART. Radiation therapy stands as a promising peri-CART and salvage treatment that can improve the outcomes of these patients. Evidence suggests that bridging radiotherapy prior to CART controls the disease during the manufacturing period, augments response rates and local control, cytoreduces/debulks the disease and decreases the severity of cytokine release syndrome, and may prolong disease-free intervals and survival especially in patients with bulky disease. Consolidative radiotherapy for residual post-CART disease alters the pattern of relapse and improves local recurrence-free and progression-free survivals. Salvage radiotherapy for relapsed post-CART disease has favorable survival outcomes when delivered comprehensively for patients with limited relapsed disease and palliates symptoms for patients with diffuse relapsed disease. The biology of the disease during the peri-CART period is poorly understood, and further studies investigating the optimal timing and dosing of radiation therapy (RT) are needed. In this review, we tackle the most significant challenges of CART, review and propose how RT can help mitigate these challenges, and provide The Mayo Clinic experts' approach on incorporating RT with CART.

Treatment of Relapsed or Refractory Diffuse Large B-Cell Lymphoma: New Approved Options

Overall, around 40% of patients with diffuse large B-cell lymphoma (DLBCL) have refractory disease or relapse after the first line of treatment. Until relatively recently, the prognosis of patients with relapsed or refractory DLBCL was very poor and treatment options were very limited. In recent years, several novel therapies have been approved that provide more effective options than conventional chemotherapy and that have manageable toxicity profiles. CAR-T cell therapy has become the new standard treatment for patients with refractory or early relapsed DLBCL, based on the positive results of the phase 3 ZUMA-7 and TRANSFORM clinical trials. This review addresses the role of CAR-T therapy and autologous stem cell transplantation in the treatment of these patients and other approved options for patients who are not candidates for transplant, such as the combinations of polatuzumab vedotin with bendamustine and rituximab, and tafasitamab with lenalidomide.

Cell-of-origin effect of polatuzumab vedotin in diffuse large B-cell lymphoma: no ordinary subgroup analysis

ABSTRACT

Subgroup analysis from the POLARIX trial of polatuzumab vedotin plus chemotherapy for untreated large B-cell lymphoma suggests greater efficacy among patients with activated B-cell subtype disease. Both preclinical and additional clinical evidence support this interaction between cell-of-origin and polatuzumab efficacy.

CD19-directed CAR T cells as first salvage therapy for large B-cell lymphoma: towards a rational approach

The approval of CD19-directed chimeric antigen receptor (CAR) T-cell therapies for the second-line treatment of high-risk large B-cell lymphoma (LBCL) has greatly affected salvage algorithms for this condition, and such therapies could have the potential to improve the course of relapsed or refractory LBCL. In this Review, we provide guidance for a rational management approach to the use of commercial CD19-directed CAR T cells in the second-line treatment of LBCL, addressing crucial questions regarding eligible histologies; age, comorbidity, and tumour biology restrictions; the handling of very aggressive tumour behaviour; and holding and bridging therapies. The guidance was developed in a structured manner and, for each question, consists of a description of the clinical issue, a summary of the evidence, the rationale for a practical management approach, and recommendations. These recommendations could help to decide on the optimal management of patients with relapsed or refractory LBCL who are considered for second-line CAR T-cell treatment.

Second-line treatment of diffuse large B-cell lymphoma: Evolution of options

In the era of immunochemotherapy, approximately 60%-70% of diffuse large B-cell lymphoma (DLBCL) patients achieve remission with first-line rituximab-based chemoimmunotherapy. However, 30%-40% relapse after initial response to first-line therapy and, out of them, 20%-50% are refractory or experience early relapse. The second-line therapy algorithm for DLBCL has recently evolved, thanks to the recent approval of new therapeutic agents or their combinations. The new guidelines suggest a stratification of relapsed/refractory (R/R) DLBCL based on the time to relapse. For transplant-eligible patients, autologous stem cell transplant remains the preferred option when the patient relapses after 12 months from diagnosis, while anti-CD19 CART-cell therapy is the current preferred choice for high-risk DLBCL, defined as primary refractory or relapse ≤12 months. For transplant-ineligible or CAR T-cell therapy-ineligible patients, the therapeutic arsenal historically lacked effective options. However, new therapeutic options, including polatuzumab vedotin combined with bendamustine-rituximab and tafasitamab with lenalidomide, have been recently approved, and novel agents such as loncastuximab tesirine, selinexor, anti-CD19 CAR T-cell therapy, and bispecific antibodies have shown promising efficacy and manageable safety in this setting offering new hope to patients in this challenging scenario.

[Efficacy and safety analysis of the zanubrutinib-based bridging regimen in chimeric antigen receptor T-cell therapy for relapsed/refractory diffuse large B-cell lymphoma]

Objective: To further elucidate the clinical efficacy and safety of a combination regimen based on the BTK inhibitor zebutanil bridging CD19 Chimeric antigen receptor T cells (CAR-T cells) in the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) . Methods: Twenty-one patients with high-risk r/r DLBCL were treated with a zanubrutinib-based regimen bridging CAR-T between June 2020 and June 2023 at the Department of Hematology, Tongji Hospital, Tongji University and the Second Affiliated Hospital of Zhejiang University, and the efficacy and safety were retrospectively analyzed. Results: All 21 patients were enrolled, and the median age was 57 years (range: 38-76). Fourteen patients (66.7%) had an eastern cooperative oncology group performance status score (ECOG score) of ≥2. Eighteen patients (85.7%) had an international prognostic index (IPI) score of ≥3. Three patients (14.3%) had an IPI score of 2 but had extranodal infiltration. Fourteen patients (66.7%) had double-expression of DLBCL and seven (33.3%) had TP53 mutations. With a median follow-up of 24.8 (95% CI 17.0-31.6) months, the objective response rate was 81.0%, and 11 patients (52.4%) achieved complete remission. The median progression-free survival (PFS) was 12.8 months, and the median overall survival (OS) was not reached. The 1-year PFS rate was 52.4% (95% CI 29.8% -74.3%), and the 1-year OS rate was 80.1% (95% CI 58.1% -94.6%). Moreover, 18 patients (85.7%) had grade 1-2 cytokine-release syndrome, and two patients (9.5%) had grade 1 immune effector cell-associated neurotoxicity syndrome. Conclusion: Zanubrutinib-based combination bridging regimen of CAR-T therapy for r/r DLBCL has high efficacy and demonstrated a good safety profile.

Clinical outcomes in transplant-eligible patients with relapsed or refractory diffuse large B-cell lymphoma after second-line salvage chemotherapy: A retrospective study

OBJECTIVE

The prognosis of patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) is poor. Although patients who fail first-line salvage chemotherapy are candidates for second-line salvage chemotherapy, the optimal treatment strategy for these patients has not yet been established.

METHODS

The present, single-center, retrospective study included transplant-eligible patients with R/R DLBCL who received second-line salvage chemotherapy with curative intent.

RESULTS

Seventy-six patients with R/R DLBCL received second-line salvage chemotherapy. Eighteen (23.7%) patients were responders to the first-line salvage chemotherapy. The overall response rate was 39.5%, and overall survival (OS) was significantly longer in patients who responded to second-line salvage chemotherapy than those who did not. Forty-one patients who proceeded to potentially curative treatment (autologous hematopoietic stem cell transplantation [ASCT], chimeric antigen receptor [CAR] T-cell therapy, or allogeneic hematopoietic stem cell transplantation) had a better prognosis than those who did not. Among the 46 patients who failed to respond to the second-line salvage regimen, only 18 (39.1%) could proceed to the curative treatments. However, among the 30 patients who responded to the second-line salvage regimen, 23 (76.7%) received one of the potentially curative treatments. Among 34 patients who received CAR T-cell therapy, OS was significantly longer in those who responded to salvage chemotherapy immediately prior to CAR T-cell therapy than in those who did not respond. In contrast, the number of prior lines of chemotherapy was not identified as a statistically significant prognostic factor of survival. No significant difference was detected in OS between patients receiving ASCT and those receiving CAR T-cell therapy after the response to second-line salvage chemotherapy.

DISCUSSION

In this study, we demonstrated that chemosensitivity remained a crucial factor in predicting survival outcomes following CAR T-cell therapy irrespective of the administration timing, and that both ASCT and CAR T-cell therapy were acceptable after the response to second-line salvage chemotherapy.

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.

Harnessing the Immune System: An Effective Way to Manage Diffuse Large B-Cell Lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a heterogenous hematological disorder with malignant potential controlled by immunological characteristics of the tumor microenvironment. Rapid breakthrough in the molecular pathways has made immunological approaches the main anchor in the management of DLBCL, with or without chemotherapeutic agents. Rituximab was the first monoclonal antibody approved for the treatment of DLBCL. Following rituximab that transformed the therapeutic landscape, other novel immunological agents including chimeric antigen T-cell therapy have reshaped the management of relapsed/refractory DLBCL. However, resistance and refractory state remain a challenge in the management of DLBCL. For this literature review, we screened articles from Medline, Embase, Cochrane databases and the European/North American guidelines from March 2010 through October 2022 for DLBCL. Here we discuss immunological agents that will significantly affect future treatment of this aggressive type of lymphoma.

Redefining Precision Management of r/r Large B-Cell Lymphoma: Novel Antibodies Take on CART and BMT in the Quest for Future Treatment Strategies

The treatment paradigms for patients with relapsed large B-cell lymphoma are expanding. Chimeric antigen receptor technology (CAR-T) has revolutionized the management of these patients. Novel bispecific antibodies and antibody-drug conjugates, used as chemotherapy-free single agents or in combination with other novel therapeutics, have been quickly introduced into the real-world setting. With such a paradigm shift, patients have an improved chance of better outcomes with unpredictable complete remission rates. Additionally, the excellent tolerance of new antibodies targeting B-cell lymphomas is another motivation to broaden its use in relapsed and refractory patients. With the increasing number of approved therapy approaches, future research needs to focus on optimizing the sequence and developing new combination strategies for these antibodies, both among themselves and with other agents. Clinical, pathological, and genetic risk profiling can assist in identifying which patients are most likely to benefit from these costly therapeutic options. However, new combinations may lead to new side effects, which we must learn to deal with. This review provides a comprehensive overview of the current state of research on several innovative antibodies for the precision management of large B-cell lymphoma. It explores various treatment strategies, such as CAR-T vs. ASCT, naked antibodies, antibody-drug conjugates, bispecific antibodies, and bispecific T-cell engagers, as well as discussing the challenges and future perspectives of novel treatment strategies. We also delve into resistance mechanisms and factors that may affect decision making. Moreover, each section provides a detailed analysis of the available literature and ongoing clinical trials.

Effective bridging therapy can improve CD19 CAR-T outcomes while maintaining safety in patients with large B-cell lymphoma

The impact of bridging therapy (BT) on CD19-directed chimeric antigen receptor T-cell (CD19CAR-T) outcomes in large B-cell lymphoma (LBCL) is poorly characterized. Current practice is guided through physician preference rather than established evidence. Identification of effective BT modalities and factors predictive of response could improve both CAR-T intention to treat and clinical outcomes. We assessed BT modality and response in 375 adult patients with LBCL in relation to outcomes after axicabtagene ciloleucel (Axi-cel) or tisagenlecleucel (Tisa-cel) administration. The majority of patients received BT with chemotherapy (57%) or radiotherapy (17%). We observed that BT was safe for patients, with minimal morbidity or mortality. We showed that complete or partial response to BT conferred a 42% reduction in disease progression and death after CD19CAR-T therapy. Multivariate analysis identified several factors associated with likelihood of response to BT, including response to last line therapy, the absence of bulky disease, and the use of polatuzumab-containing chemotherapy regimens. Our data suggested that complete or partial response to BT may be more important for Tisa-cel than for Axi-cel, because all patients receiving Tisa-cel with less than partial response to BT experienced frank relapse within 12 months of CD19CAR-T infusion. In summary, BT in LBCL should be carefully planned toward optimal response and disease debulking, to improve patient outcomes associated with CD19CAR-T. Polatuzumab-containing regimens should be strongly considered for all suitable patients, and failure to achieve complete or partial response to BT before Tisa-cel administration may prompt consideration of further lines of BT where possible.

Novel agents in relapsed/refractory diffuse large B-cell lymphoma

Patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL), ineligible for or relapsing after autologous stem-cell transplant or chimeric antigen-receptor T-cell therapies have poor outcomes. Several novel agents, polatuzumab vedotin, tafasitamab, loncastuximab tesirine, and selinexor, have been approved and offer new opportunities for this difficult to treat population. Studies are evaluating combination of these agents with chemotherapy and other emerging therapies. Additionally, advances in our understanding of DLBCL biology, genetics, and immune microenvironment have allowed for the identification of new therapeutic targets like Ikaros and Aiolos, IRAK4, MALT1, and CD47 with several agents in ongoing clinical trials. In this chapter we review updated data supporting the use of the approved agents and discuss other emerging novel therapies for patients with R/R DLBCL.

Outcomes of polatuzumab vedotin-containing regimens in real-world setting of relapsed and or refractory diffuse large B-cell lymphoma patients: a matched-control analysis from the Thai Lymphoma Study Group (TLSG)

Relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) is a challenging condition to treat, and there is an unmet clinical need for effective therapies. Recently, polatuzumab vedotin (Pola), an anti-CD79b antibody-drug-conjugate (ADC), combined with bendamustine-rituximab (BR), has been approved for R/R DLBCL patients. However, real-world data on Pola-based regimens in R/R DLBCL patients, especially in Thailand, are limited. This study aimed to evaluate the efficacy and safety of Pola-based salvage treatment in R/R DLBCL patients in Thailand. Thirty-five patients who received Pola-based treatment were included in the study, and their data were compared to 180 matched patients who received non-Pola-based therapy. The overall response rate (ORR) in the Pola group was 62.8%, with complete remission and partial remission rates of 17.1% and 45.7%, respectively. The median progression-free survival (PFS) and overall survival (OS) were 10.6 months and 12.8 months, respectively. The study found a significantly higher ORR in Pola-based salvage treatments compared to non-Pola-based therapy (62.8% vs. 33.3%). The survival outcomes were also significantly superior in the Pola group, with longer median PFS and OS than the control group. Grades 3-4 adverse events (AEs) were mainly hematological, and they were tolerable. In conclusion, this study provides real-world evidence of the efficacy and safety of Pola-based salvage treatment in R/R DLBCL patients in Thailand. The results of this study are promising and suggest that Pola-based salvage treatment could be a viable option for R/R DLBCL patients who have limited treatment options.

Long-term outcomes following CAR T cell therapy: what we know so far

Chimeric antigen receptors (CAR) are engineered fusion proteins designed to target T cells to antigens expressed on cancer cells. CAR T cells are now an established treatment for patients with relapsed and/or refractory B cell lymphomas, B cell acute lymphoblastic leukaemia and multiple myeloma. At the time of this writing, over a decade of follow-up data are available from the initial patients who received CD19-targeted CAR T cells for B cell malignancies. Data on the outcomes of patients who received B cell maturation antigen (BCMA)-targeted CAR T cells for multiple myeloma are more limited owing to the more recent development of these constructs. In this Review, we summarize long-term follow-up data on efficacy and toxicities from patients treated with CAR T cells targeting CD19 or BCMA. Overall, the data demonstrate that CD19-targeted CAR T cells can induce prolonged remissions in patients with B cell malignancies, often with minimal long-term toxicities, and are probably curative for a subset of patients. By contrast, remissions induced by BCMA-targeted CAR T cells are typically more short-lived but also generally have only limited long-term toxicities. We discuss factors associated with long-term remissions, including the depth of initial response, malignancy characteristics predictive of response, peak circulating CAR levels and the role of lymphodepleting chemotherapy. We also discuss ongoing investigational strategies designed to improve the length of remission following CAR T cell therapy.

Antibody-drug conjugates: in search of partners of choice

Antibody-drug conjugates (ADCs) have become a credentialled class of anticancer drugs for both solid and hematological malignancies, with regulatory approvals mainly as single agents. Despite extensive preclinical and clinical efforts to develop rational ADC-based combinations, to date only a limited number have demonstrated survival improvements over standard of care. The most appealing partners for ADCs are those that offer additive or synergistic effects on tumor cells or their microenvironment without unacceptable overlapping toxicities. Coadministration with antiangiogenic compounds, HER2-targeting drugs, DNA-damage response agents and immune checkpoint inhibitors (ICIs) represent active forerunners. Through the identification of targets with tumor-specific expression, improved conjugation technologies, and novel linkers and payloads offering superior therapeutic indices, the next generation of ADCs brings optimism to combinatorial approaches.

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.

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.

Outcomes of first therapy after CD19-CAR-T treatment failure in large B-cell lymphoma

Persistence or recurrence of large B-cell lymphoma after CD19-CAR-T is common, yet data guiding management are limited. We describe outcomes and features following CAR-T treatment failure. Of 305 adults who received CD19-CAR-T, 182 experienced disease recurrence or progression (1-year cumulative incidence 63% [95%CI: 57-69]). Of 52 post-CAR-T biopsies evaluated by flow cytometry, 49 (94%) expressed CD19. Subsequent anti-cancer treatment was administered in 135/182 (74%) patients with CAR-T treatment failure. Median OS from the first post-CAR-T treatment was 8 months (95%CI 5.6-11.0). Polatuzumab-, standard chemotherapy-, and lenalidomide-based treatments were the most common approaches after CAR-T. No complete responses (CRs) were observed with conventional chemotherapy, while CR rates exceeding 30% were seen following polatuzumab- or lenalidomide-based therapies. Factors associated with poor OS among patients treated post-CAR-T were pre-CAR-T bulky disease (HR 2.27 [1.10-4.72]), lack of response to CAR-T (2.33 [1.02-5.29]), age >65 years (HR 2.65 [1.49-4.73]) and elevated LDH at post-CAR-T treatment (HR 2.95 [1.61-5.38]). The presence of ≥2 of these factors was associated with inferior OS compared to ≤1 (56% vs. 19%). In this largest analysis to date of patients who progressed or relapsed after CD19-CAR-T, survival is poor, though novel agents such as polatuzumab and lenalidomide may have hold promise.

Impact of Implementing a Bendamustine-Based Conditioning Regimen on Outcomes of Autologous Stem Cell Transplantation in Lymphoma while Novel Cellular Therapies Emerge

With the advent of new cellular and targeted therapies, treatment options for relapsed and refractory (r/R) lymphomas have multiplied, and the optimal approach offering the best outcomes remains a matter of passionate debate. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is still considered a treatment option for patients with chemosensitive lymphoma when cure is the expected goal. The myeloablative conditioning regimen preceding the stem cell infusion is considered the effective component of this approach. Carmustine (BCNU)-based preparative regimens, such as BEAM and BEAC, are considered the standard of care and have shown efficacy and low nonrelapse mortality (NRM). Comparative studies between conditioning regimens have failed to identify a better option. After a BCNU drug shortage in Canada followed by a steep increase in price, we elected to substitute BCNU for bendamustine (benda) in the preparative regimen. The purpose of this substitution was to improve response while preserving safety and controlling costs. From May 2015 to May 2018, a total of 131 consecutive lymphoma patients received benda-EAM conditioning. These patients were compared with 96 consecutive patients who received BCNU-based conditioning from January 2012 to May 2015. Apart from conditioning, supportive care measures were the same in the 2 groups. Patients receiving benda were older (55.7 years versus 51.1 years; P = .002). The development of grade ≥3 mucositis was more frequent with benda conditioning (39.5% versus 7.8%; P < .001) leading to a greater requirement for parenteral nutrition (48.9% versus 21.9%; P < .001). A transient creatinine increase >1.5 times the upper limit of normal (15.3% versus 4.2%; P < .008) and intensive care unit admission (6.9% versus 1.1%; P < .029) were more frequent with benda; however, there were no between-group differences in cardiac, pulmonary, or liver toxicity and NRM. With a median follow-up of 48 months for the benda group and 60 months for the BCNU group, benda was associated with significantly better progression-free survival (71% versus 61%; P = .040; hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.0 to 2.7) and overall survival (86% vs 71%; P = .0066; HR, 2.6; 95% CI, 1.3 to 5.4) compared with BCNU-based conditioning regimens. While novel therapies emerge, our study demonstrates that benda-EAM is safe and effective and should be considered a valid alternative to BCNU conditioning to improve outcomes of patients with chemosensitive r/R lymphomas undergoing ASCT.

Diffuse Large B-Cell Lymphoma (DLBCL): Early Patient Management and Emerging Treatment Options

Diffuse large B-cell lymphoma (DLBCL) represents a curable disease with a 60-70% chance of cure with current R-CHOP chemoimmunotherapy. However, 30-40% of patients are refractory or relapsing. Many attempts failed to improve the outcome of DLBCL patients, including the intensification of R-CHOP regimen, consolidation, or maintenance therapy since the introduction of R-CHOP in 2000. Better understanding of both molecular biology of lymphoma cells and the tumor microenvironment raised the hope for future improvement of DLBCL patients' survival. Novel molecular findings have initiated clinical trials exploring targeted therapy based on driver genetic alterations with an intent to improve survival of high-risk subsets of patients. But the preliminary results remain ambiguous. The approach "agnostic" to specific molecular alterations of lymphoma cell includes antibody-drug conjugates (especially polatuzumab vedotin), immunotherapy comprising different antibodies with immunomodulatory effect (tafasitamab, lenalidomide), and T-cell engaging therapy (bispecific antibodies, early use of CAR T-cell). This approach could increase the cure rates and change the current therapeutic paradigm. However, better prognostic stratification, smarter designs of clinical trials, modification of endpoints including the use of ctDNA are needed. This review covers the complexity of DLBCL management.

Predictors of response to axicabtagene-ciloleucel CAR T cells in aggressive B cell lymphomas: A real-world study

Chimeric antigen receptor T-cell (CAR T) therapy has shown promising efficacy in relapsed and refractory diffuse large B cell lymphoma (DLBCL). While most patients undergo CAR T infusion with active disease, the impact of some clinical variables, such as responsiveness to the pre-CAR T chemotherapy on the response to CAR T, is unknown. In this single-institution study, we studied the impact of several pre-CAR T variables on the post-CAR outcomes. Sixty patients underwent apheresis for axicabtagene-ciloleucel (axi-cel) and 42 of them (70.0%) had primary refractory disease. Bridging therapy between apheresis and lymphodepletion was given in 34 patients (56.7%). After axi-cel, the overall response rate was 63.3%. Responsiveness to the immediate pre-CAR T therapy did not show a significant association with response to axi-cel, progression-free (PFS) or overall (OS) survival. Multivariable analysis determined that bulky disease before lymphodepletion was independently associated with inferior outcomes, and patients that presented with high-burden disease unresponsive to immediate pre-CAR T therapy had a dismal outcome. This data supports proceeding with treatment in CAR T candidates regardless of their response to immediate pre-CAR T therapy. Interim therapeutic interventions should be considered in patients who have known risk factors for poor outcomes (bulky disease, high LDH).

Polatuzumab vedotin, rituximab, and bendamustine combination in relapsed or refractory diffuse large B-cell lymphoma: a real-world data from Turkey

Polatuzumab vedotin (Pola) with bendamustine and rituximab (BR) is a promising option for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). We analyzed the data of 71 R/R DLBCL patients who had been treated with Pola-BR in the named patient program from March 2018 to April 2021 from 32 centers in Turkey. All patients received up to six cycles of Pola 1.8 mg/kg, rituximab 375 mg/m² on day 1, and bendamustine 90 mg/m² on days 1-2 of each cycle. Median age at Pola-BR initiation was 55 (19-84). The overall response rate was 47.9%, including 32.4% CR rate when a median of 3 cycles was applied. With a median follow-up of 5 months, the median OS was 5 months. Grade 3-4 neutropenia and thrombocytopenia were the most common hematological toxicities. The real-world data from our cohort showed the Pola-BR is an effective option with a manageable toxicity profile.

Association of bridging therapy utilization with clinical outcomes in patients receiving chimeric antigen receptor (CAR) T-cell therapy

Background

Chimeric antigen receptor (CAR) T-cell therapy recipients may receive bridging therapy while awaiting product manufacturing to control disease. Yet, data are lacking regarding the impact of bridging therapy use on clinical outcomes.

Methods

We conducted a retrospective analysis of 235 patients who received CAR T-cell therapy at two tertiary care centers from February 2016 to December 2019. We abstracted clinical outcomes from review of the electronic health record including (1) overall response; (2) complete response (CR); (3) progression-free survival (PFS); (4) overall survival (OS); and (5) toxicity (cytokine release syndrome (CRS) and neurotoxicity). We assessed the association of bridging therapy use with overall response rate (ORR) and CR rate using multivariable logistic regression and with PFS and OS using multivariable Cox regression controlling for covariates. We analyzed the association of bridging therapy use with CRS and neurotoxicity using Fisher’s exact test.

Results

Patients’ median age was 63.1 years (range: 19–82), and the majority were men (144/235, 61.3%). Most patients received axicabtagene ciloleucel (192/235, 81.7%), and the most common lymphoma subtype was diffuse large B-cell lymphoma or grade 3B follicular lymphoma (107/235, 45.5%). Overall, 39.4% (93/236) received bridging therapy. Bridging therapy regimens included systemic chemotherapy (48/92, 52.2%), corticosteroids (25/92, 27.2%), radiation (9/92, 9.8%), and other systemic therapies (10/92, 10.9%). In multivariable Cox regression, bridging therapy use was associated with OS (HR: 1.97, p=0.004) but not PFS (HR: 1.18, p=0.449). In multivariable logistic regression, bridging therapy use was not associated with ORR (OR: 0.69, p=0.391) or CR rate (OR: 0.96, p=0.901). We did not identify an association of bridging therapy use with grade 3+ CRS (p=0.574) or grade 3+ neurotoxicity (p=0.748).

Conclusions

We identified that bridging therapy use is not associated with differences in ORR, CR rate, or PFS but is associated with worse OS. These data suggest bridging therapy may be a surrogate for additional poor prognostic factors leading to inferior OS and underscore the need for novel bridging therapy regimens to optimize outcomes in this patient population.

Combination strategies to optimize the efficacy of chimeric antigen receptor T cell therapy in haematological malignancies

Chimeric antigen receptor (CAR) T cell therapy has revolutionized the therapeutic landscape of haematological malignancies. However, resistance and relapse remain prominent limitations, and they are related to the limited persistence and efficacy of CAR T cells, downregulation or loss of tumour antigens, intrinsic resistance of tumours to death signalling, and immune suppressive microenvironment. Rational combined modality treatments are regarded as a promising strategy to further unlock the antitumor potential of CAR T cell therapy, which can be applied before CAR T cell infusion as a conditioning regimen or in ex vivo culture settings as well as concomitant with or after CAR T cell infusion. In this review, we summarize the combinatorial strategies, including chemotherapy, radiotherapy, haematopoietic stem cell transplantation, targeted therapies and other immunotherapies, in an effort to further enhance the effectiveness of this impressive therapy and benefit more patients.

CAR T-Cell Therapy Predictive Response Markers in Diffuse Large B-Cell Lymphoma and Therapeutic Options After CART19 Failure

Immunotherapy with T cells genetically modified with chimeric antigen receptors (CARs) has shown significant clinical efficacy in patients with relapsed/refractory B-cell lymphoma. Nevertheless, more than 50% of treated patients do not benefit from such therapy due to either absence of response or further relapse. Elucidation of clinical and biological features that would predict clinical response to CART19 therapy is of paramount importance and eventually may allow for selection of those patients with greater chances of response. In the last 5 years, significant clinical experience has been obtained in the treatment of diffuse large B-cell lymphoma (DLBCL) patients with CAR19 T cells, and major advances have been made on the understanding of CART19 efficacy mechanisms. In this review, we discuss clinical and tumor features associated with response to CART19 in DLBCL patients as well as the impact of biological features of the infusion CART19 product on the clinical response. Prognosis of DLBCL patients that fail CART19 is poor and therapeutic approaches with new drugs are also discussed.

Case Report: Subtotal Lymphoid and Total Marrow Irradiation as Bridge Therapy to CD19-Directed CAR T Cells in a Chemorefractory DLBCL With Leukemic Involvement

CAR T cell therapy has transformed the salvage approach for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). Maintaining disease control before CAR T cell infusion during product manufacturing (so-called bridging therapy) is an important step to optimizing outcome. Among possible bridging therapies, radiation therapy (RT) represents a valuable option, particularly when the disease is limited. Here, we report for the first time on a patient with chemorefractory-transformed DLBCL showing nodal, extranodal, and massive bone marrow (BM) lymphoma infiltration associated with leukemic involvement, a successful bridge therapy to CD19-directed CAR T cell therapy by subtotal lymphoid/total marrow irradiation plus thiothepa followed by reinfusion of CD34+ autologous hematopoietic stem cells. Such a novel bridging regimen allowed a significant reduction of nodal and BM tumor volume while improving blood cell count before CAR T cell infusion. The PET-CT scan and BM evaluation performed at 1, 3, and 6 months after treatment showed complete remission of the disease. A relapse occurred at almost 1 year in lymph nodes because of CD19 antigen escape while the BM remained free of disease. This extended radiotherapy approach may be an effective bridging therapy for chemorefractory DLBCL patients eligible for CAR T cells who present with a high tumor burden, including massive BM involvement associated with leukemic involvement. This preliminary evidence is worth confirming in additional patients.

Effect of Prior Therapy and Disease Refractoriness on the Efficacy and Safety of Oral Selinexor in Patients with Diffuse Large B-cell Lymphoma (DLBCL): A Post-hoc Analysis of the SADAL Study

BACKGROUND

Despite a number of treatment options, patients with diffuse large B-cell lymphoma (DLBCL) whose disease has become refractory to treatment have a poor prognosis. Selinexor is a novel, oral drug that is approved to treat patients with relapsed/refractory DLBCL. In this post hoc analysis of the SADAL study, a multinational, open-label study, we evaluated subpopulations to determine if response to single agent selinexor is impacted by number of lines of prior treatment, autologous stem cell transplant (ASCT), response to first and most recent therapies, and time to progressive disease.

PATIENTS

Patients (n = 134) with DLBCL after 2-5 prior therapies were enrolled in SADAL and received 60mg selinexor twice weekly.

RESULTS

The median overall survival was 9.0 months and median progression free survival was 2.6 months. Patients who had the best overall response rate (ORR) and disease control rate were those who had prior ASCT (42.5% and 50.0%) or responded to last line of therapy (35.9% and 43.5%). Patients with primary refractory DLBCL also showed responses (ORR 21.8%). Adverse events between subgroups were similar to the overall study population, the most common being thrombocytopenia (29.1%), fatigue (7.5%), and nausea (6.0%).

CONCLUSION

Regardless of prior therapy and disease refractory status, selinexor treatment demonstrated results consistent with its novel mechanism of action and lack of cross-resistance. Thus, single agent oral selinexor can induce deep, durable, and tolerable responses in patients with DLBCL who have recurrent disease after several chemoimmunotherapy combination regimens.

Polatuzumab vedotin in relapsed / refractory aggressive B-cell lymphoma

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive lymphoma histology. Outcomes for patients with relapsed or refractory (R/R) disease remain suboptimal. Polatuzumab vedotin (polatuzumab) is a recently approved antibody drug conjugate that targets CD79b, with a tubulin toxin payload, that has demonstrated significant clinical activity and an acceptable toxicity profile when administered with both anti-CD20 monoclonal antibodies and chemotherapy in clinical trials.

AREAS COVERED

In this article, we discuss the early-phase trials supporting the accelerated FDA approval of polatuzumab for patients with R/R DLBCL and review the status of and data from ongoing trials combining polatuzumab with other agents.

EXPERT OPINION

Polatuzumab is an important new tool for the management of patients with R/R DLBCL who are ineligible for or who relapse following standard second-line therapies. Combinations of polatuzumab with other agents may represent an opportunity to improve outcomes for this difficult to treat population. The recent publication of the POLARIX trial (NCT03274492) incorporating polatuzumab in the frontline treatment of DLBCL may impact the future role of this agent in the R/R setting.

Novel Immune-Based treatments for Diffuse Large B-Cell Lymphoma: The Post-CAR T Cell Era

Prognosis for patients with refractory/relapsed (R/R) diffuse large B-cell lymphoma (DLBCL) is poor. Immune-based therapeutic treatments such as CD19 Chimeric Antigen Receptor (CAR) T cell therapies have dramatically changed the treatment landscape for R/R DLBCL leading to durable remissions in ~ 50% of patients. However, there remains an unmet need for developing novel therapies to improve clinical outcomes of patients not responding or relapsing after CAR T cell therapies. Lack of suitable immunotherapeutic targets and disease heterogeneity represent the foremost challenges in this emerging field. In this review, we discuss the recently approved and emerging novel immunotherapies for patients with R/R DLBCL in the post-CAR T era and the cell surface targets currently used.

Systematic review and meta-analysis of the association between bridging therapy and outcomes of chimeric antigen receptor T cell therapy in patients with large B cell lymphoma

BACKGROUND

The existing evidence about the impact of bridging therapy (BT) on chimeric antigen receptor (CAR)-T cell therapy in patients with large B cell lymphoma (LBCL) is conflicting. Therefore, we reviewed all available evidence to examine the association between BT and CAR-T therapy outcomes by systematic review and meta-analysis approach.

METHODS

Two reviewers independently searched Embase, PubMed, Web of Science, and Cochrane library to identify all records that described BT for LBCL treated with CAR-T. We then applied a fixed- or random-effects meta-analysis to estimate the pooled hazard ratios (HRs) and rate ratio (RRs) for efficacy and safety endpoints and assessed differences across various BT modalities. The Newcastle-Ottawa Scale was used to evaluate study quality.

RESULTS

Twenty-six reports from 24 studies involving 2014 patients were included in the analysis. Pooled results showed that patients requiring BT had significantly worse 1-year overall survival rate (RR = 0.76, 95% confidence interval [CI] 0.68-0.85, P < 0.001), 1-year progression-free survival rate (RR = 0.71, 95% CI 0.60-0.85, P < 0.001), progression-free survival (HR = 1.35, 95% CI 1.07-1.69, P = 0.01), overall response rate (RR = 0.88, 95% CI 0.81-0.95, P = 0.001), complete response rate (RR = 0.78, 95% CI 0.65-0.93, P = 0.005), and grade ≥3 immune effector cell-associated neurotoxicity syndrome (RR = 1.43, 95% CI 1.10-1.87, P = 0.007), and tended to have poorer overall survival (HR = 1.42, 95% CI 0.99-2.02, P = 0.056) and grade ≥3 cytokine release syndrome (RR = 1.59, 95% CI 0.92-2.75, P = 0.096). Prolonged cytopenias were the common toxicity event associated with BT. Radiotherapy may serve as a promising BT option that can provide safe and effective disease control for patients with LBCL before CAR-T infusion. The inconsistency of patient baselines in the current study hindered further comparisons between different BT modalities. Most of the available evidence was rated as low quality because of concerns over low comparability.

CONCLUSION

BT appears to be associated with comparatively poor efficacy and safety outcomes after CAR-T infusion. However, due to the considerable heterogeneity between the BT and non-BT cohorts at disease baseline, no definitive conclusions can be made for the true impact of BT on CAR-T until further randomized studies are conducted.

A multicenter retrospective study of polatuzumab vedotin in patients with large B-cell lymphoma after CAR T-cell therapy

Polatuzumab vedotin (PV) is an antibody-drug conjugate targeting CD79b that is approved for patients with relapsed/refractory large B-cell lymphoma (LBCL). Patients who relapse after chimeric antigen receptor (CAR) T-cell therapy were not included in the registration study, and reports of PV use after CAR T cells are limited. This multicenter retrospective analysis included patients with LBCL who relapsed or progressed after CAR T-cell therapy and subsequently received PV with or without rituximab and bendamustine between July 2019 and May 2021. Response to treatment and progression were assessed based on the 2014 Lugano criteria. Fifty-seven patients were included in the study: 18 (32%) patients were primary refractory to CAR T-cell therapy, and 34 (60%) patients received PV-based therapy immediately after CAR T-cell therapy. PV was combined with rituximab in 54 (95%) patients and administered with bendamustine in 35 (61%) patients. A response was achieved in 25 (44%) patients, including complete remission in 8 (14%). No significant association between baseline characteristics and response was observed. After a median follow-up of 47 weeks (95% confidence interval [CI], 40-54), 46 (81%) patients had disease progression or died, and the median progression-free survival was 10 weeks (95% CI, 5-15). On a multivariate analysis, bone marrow involvement (hazard ratio, 5.2; 95% CI, 1.8-15; P = .003) and elevated lactate dehydrogenase levels (hazard ratio, 5.0; 95% CI, 1.4-16; P = .01) were associated with shorter progression-free survival. Studies aimed at better characterizing the intrinsic mechanism of resistance and identifying optimal consolidation strategies for these patients are warranted.

Monoclonal antibodies used for the management of haematological disorders

INTRODUCTION

Monoclonal antibodies Ab (MoAb) are increasingly becoming part of therapeutic armamentarium for haematologists and haemato-oncologists. This review brings together commonly used antibodies in one place for brevity and novel understanding.

AREAS COVERED

Pubmed and Scopus databases were explored focusing on MoAb in clinical haematological practice. Emphasis was given to current review articles. The data base was searched from 1997 till present. 24 different antibodies, most of which are in use were discussed. Antibodies are used for diverse conditions i.e. malignant and benign haematological conditions, treatment at various phases of stem cell transplantation. These antibodies were used both alone or in combination with various chemotherapy, targeted small molecules or as immunoconjugates. Some of the side effect profiles of these antibodies were common and some were unique. Unusual infections or organ dysfunctions were noted. Improved function of antibodies by protein engineering is also advancing rapidly. Dosage, frequency and route of administration depended on the convenience and condition for which the antibody is used.

EXPERT OPINION

: MoAbs are increasingly used in haematology practice either alone or in combination with other types of therapy for improved out come in various haematological conditions.

Polatuzumab vedotin plus bendamustine and rituximab in patients with relapsed/refractory diffuse large B-cell lymphoma in the real world

OBJECTIVES

Polatuzumab vedotin with bendamustine and rituximab (Pola-BR) was approved for treatment of transplant-ineligible patients with relapsed/refractory DLBCL (R/R DLBCL). However, the number of patients treated in the GO29365 trial including the extension cohort was limited, and more data evaluating the efficacy of this treatment regimen is needed.

METHODS

We analyzed 21 patients with R/R DLBCL to determine real-life efficacy and safety of Pola-BR regimen. Data of all patients entered the database of the NiHiL project (NCT03199066).

RESULTS

Median overall survival was 8.7 months, and progression-free survival 3.8 months. The overall response rate was 33%. Grade 3-4 neutropenia was detected in 29%, thrombocytopenia in 38%, anemia in 19%, infections in 24% cases, and peripheral neuropathy in 5%. Discontinuation of treatment was caused by progression in 50%, adverse events in 31%, and intended bridging to CAR-T therapy in 19%.

CONCLUSION

Although the outcome of patients is worse than in GO29365 trial, the use of Pola-BR regimen in the real world demonstrates tolerable toxicity profile and efficacy in transplant-ineligible patients with R/R DLBCL. Moreover, this regimen might represent a perspective option as a bridge to CAR-T therapy.

Pixantrone in patients with relapsed/refractory diffuse large B-cell lymphoma: A real-life, retrospective, multicenter trial on behalf of the "RTL" (Regional Tuscan Lymphoma network)

INTRODUCTION

Pixantrone is a novel aza-anthracenedione with antineoplastic activity, currently approved for multiply relapsed/refractory diffuse large B-cell lymphoma (DLBCL), even if real-life data are limited.

METHODS

We investigated pixantrone efficacy and safety in clinical practice, as 3^rd or 4^th line therapy. We retrospectively analyzed a cohort of 37 R/R DLBCL patients managed in 8 Tuscan onco-hematological centers. Pixantrone, 50 mg/m² , was administered on days 1, 8, 15 of a 28 days cycle for up to 6 cycles. Response to therapy was evaluated according to the Lugano 2014 classification.

RESULTS

Pixantrone was administered as 3^rd or 4^th line in 24/37 (64.9%) and 13/37 (35.1%) cases. Overall response rate and CR rate were 43.2% and 32.4%. After a median follow-up of 6 months, 17/37 patients (46%) were alive, the main cause of death was progressive disease (14/37 cases, 37.9%). Median PFS was 3 months, median DOR was 17.9 months, and median OS was 9.7 months. A significant proportion of patients achieved a long-lasting response >12 months (8/37 cases). IPI>2 showed a trend toward inferior PFS.

CONCLUSION

In this real-life setting, pixantrone demonstrated appreciable efficacy in a population with poor prognosis; in a small proportion of cases, it can be associated with long-term remission.

Monoclonal Antibodies in the Treatment of Diffuse Large B-Cell Lymphoma: Moving beyond Rituximab

Although rituximab has revolutionized the treatment of diffuse large B-cell lymphoma (DLBCL), a significant proportion of patients experience refractory disease or relapse early after the end of treatment. The lack of effective treatment options in the relapsed/refractory (R/R) setting had made the prognosis of these patients dismal. The initial enthusiasm for novel anti-CD20 antibodies had been short-lived as they failed to prove their superiority to rituximab. Therefore, research has focused on developing novel agents with a unique mechanism of action. Among them, two antibody-drug conjugates, namely polatuzumab vedotin (PolaV) and loncastuximab tesirine, along with tafasitamab, an anti-CD19 bioengineered antibody, have been approved for the treatment of R/R DLBCL. Whereas PolaV has been FDA and EMA approved, EMA has not approved loncastuximab tesirine and tafasitamab yet. Results from randomized trials, as well as real-life data for PolaV have been promising. Novel agents as bispecific antibodies bridging CD3 on T-cells to CD20 have shown very promising results in clinical trials and are expected to gain approval for treatment of R/R DLBCL soon. As the therapeutic armamentarium against DLBCL is expanding, an improvement in survival of patients with R/R and higher cure rates might soon become evident.

Revising the Treatment Pathways in Lymphoma: New Standards of Care-How Do We Choose?

Diffuse large B-cell lymphoma and follicular lymphoma are the most commonly encountered non-Hodgkin lymphomas in clinical practice. Both are biologically heterogeneous, with management strategies that are becoming increasingly complex. Diffuse large B-cell lymphoma typically exhibits aggressive behavior but can be cured in the majority of cases with immunochemotherapy. While R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) has been the standard of care for decades, the recent combination of polatuzumab-vedotin-R-CHP (rituximab plus cyclophosphamide, doxorubicin, and prednisone) has demonstrated improved progression-free survival for patients with intermediate- and intermediate-high-risk disease. Numerous novel therapies, including targeted agents and immunotherapy-based approaches, have recently been approved for relapsed/refractory disease and have led to improved outcomes. Follicular lymphoma is an indolent lymphoma that remains incurable with standard approaches. Overall survival in most patients is excellent, although a proportion of patients will have early relapsing disease and poorer outcomes. The availability of novel agents in the relapsed/refractory setting has shifted the treatment algorithm, which requires thoughtful consideration of sequencing. This article will review recent developments in the treatment of diffuse large B-cell lymphoma and relapsed/refractory follicular lymphoma.

Preparing for CAR T cell therapy: patient selection, bridging therapies and lymphodepletion

Chimeric antigen receptor (CAR) T cells have emerged as a potent therapeutic approach for patients with certain haematological cancers, with multiple CAR T cell products currently approved by the FDA for those with relapsed and/or refractory B cell malignancies. However, in order to derive the desired level of effectiveness, patients need to successfully receive the CAR T cell infusion in a timely fashion. This process entails apheresis of the patient's T cells, followed by CAR T cell manufacture. While awaiting infusion at an authorized treatment centre, patients may receive interim disease-directed therapy. Most patients will also receive a course of pre-CAR T cell lymphodepletion, which has emerged as an important factor in enabling durable responses. The time between apheresis and CAR T cell infusion is often not a simple journey, with each milestone being a critical step that can have important downstream consequences for the ability to receive the infusion and the strength of clinical responses. In this Review, we provide a summary of the many considerations for preparing patients with B cell non-Hodgkin lymphoma or acute lymphoblastic leukaemia for CAR T cell therapy, and outline current limitations and areas for future research.

Management of relapsed or refractory large B-cell lymphoma in patients ineligible for CAR-T cell therapy

INTRODUCTION

Chimeric antigen receptor T (CAR-T) therapy has revolutionized the treatment of relapsed/refractory large B-cell lymphoma (LBCL). However, patients who are excluded or have no access to CAR-T represent a challenge for clinicians and have generally a dismal outcome. The landscape for this category of patients is constantly evolving: new agents have been approved in the last 2-3 years, alone or in combination, and novel treatment modalities are under investigations.

AREAS COVERED

Thereafter, we reviewed the currently available therapeutic strategies: conventional chemotherapy, Antibody-drug conjugate ADC (mainly polatuzumab and loncastuxumab), bispecific antibodies (CD19/CD3 and focus on novel CD20/CD3 Abs), immunomodulatory drugs (covering tafasitamab and lenalidomide, checkpoint inhibitors mainly in PMBL), small molecules (selinexor, BTK and PI3K inhibitors), and the role of radiotherapy.

EXPERT OPINION

Navigating this scenario, will uncover new challenges, including identifying an ideal sequence for these therapies, the most effective combinations, and search for consistent predictive factors to help selecting the appropriate population of LBCL patients. At present, supporting clinical research for CAR-T ineligible patients, a new and challenging group, must remain a major focus that is complementary to advances in CAR T-cell therapy.

Results of a UK real world study of polatuzumab vedotin, bendamustine, and rituximab for relapsed/refractory large B-cell lymphoma

The addition of polatuzumab vedotin to bendamustine and rituximab (Pola-BR) has been shown to improve overall survival (OS) in stem cell transplant (SCT)-ineligible patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). It is also increasingly used as bridging to CAR T-cell therapy (CAR-T). We retrospectively analysed the efficacy of Pola-BR in 133 patients at 28 UK institutions. Treatment intent was bridging to CAR-T for N=40, re-induction with planned SCT for N=13 and stand-alone treatment for N=78. The overall response rate (ORR) was 57.0% (complete response (CR) 32.8%). After median 7.7 months follow-up, median PFS and OS were 4.8 months and 8.2 months respectively. For stand-alone treatment shortened PFS was associated with bulk disease (&gt;7.5cm) (HR 2.32 (95% CI 1.23-4.38), p=0.009), &gt;1 prior treatment (HR 2.17 (95% CI 1.19-3.95), p=0.01) and refractoriness to the last treatment (HR 3.48 (95% CI 1.79-6.76), p&lt;0.001). For CAR-T bridging the ORR was 42.1% (CR 18.4%) and for treatment after CAR-T failure the ORR was 43.8% (CR 18.8%). These data demonstrate efficacy for Pola-BR as a treatment for SCT-ineligible patients with R/R DLBCL, help to delineate which patients may benefit most, and provide preliminary evidence of efficacy as bridging to CAR-T and after CAR-T failure.

Chimeric antigen receptor T-cell (CAR-T) therapy in patients with aggressive B-cell lymphomas. Current outlook after a decade of treatment

Chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the management of patients with diffuse large B-cell lymphoma (DLBCL) who are refractory or relapse after immunochemotherapy. This strategy consists in genetically modifying the patient's own T lymphocytes to favor the recognition of selected tumor antigens. Currently, we have two anti-CD19 CAR-T drugs approved in Spain for patients with DLBCL after two or more prior treatment lines and there are multiple ongoing clinical trials exploring earlier lines of treatment. Both clinical trials and post-marketing real-world data have contributed to better define the efficacy and safety profile of each construct, identifying the main prognostic response factors and improving the management of each step in this therapy. All these aspects are reviewed herein.