Single-agent lenalidomide in patients with mantle-cell lymphoma who relapsed or progressed after or were refractory to bortezomib: phase II MCL-001 (EMERGE) study

Indolent lymphoma: addressing the needs of survivors

Over the past two decades, there has been a continuous improvement in outcome for patients with indolent lymphoma (iNHL) resulting in a gradual accumulation of survivors. While life expectancy in the current era approaches that of the lymphoma-free population, patients continue to experience lifelong complications of the disease and its treatment affecting general health, emotional, psychological and social wellbeing, relationships, employment, finances, and fitness. Contemporary care models while suited to the management of lymphoma are often lacking when it comes to identification and management of these additional needs. Given improvements in physical survival achieved over the past decades, it is timely for us to focus on other issues affecting patient wellbeing including immunodeficiency and infection, second cancers, cardiovascular disease, bone health, psychological wellbeing, and sexual health. Many of these aspects are in the domain of the primary care physician; however, there is limited guidance on how these issues should be addressed. It is now time for us to engage our patients, their caregivers, and other healthcare providers in care aspects beyond the lymphoma diagnosis, so they can anticipate a rich and full life, free from both direct and indirect consequences of the lymphoma diagnosis.

Challenges of treating mantle cell lymphoma in older adults

Mantle cell lymphoma (MCL) is a rare, incurable B-cell non-Hodgkin lymphoma and over half of patients affected are older adults (≥65 years of age). New targeted treatments for MCL have emerged over the past two decades. Nonetheless, MCL-specific death rates for older adults remain elevated compared with younger adults, demonstrating the challenge of treating this population. The older adult population is at risk for overtreatment or undertreatment. Clinicians must be mindful of how to optimize the holistic care of older adults receiving treatment for MCL. Evaluating fitness through a geriatric assessment (GA) is an important step when choosing therapy. The treatment armamentarium includes both chemotherapy and non-chemotherapy options and toxicities must be considered in the context of the patient's GA and proactively managed. Herein, the treatment of MCL in older adults is reviewed and strategies for choosing treatment are offered to assist in treatment decision-making for this challenging population.

Recent Updates of PET in Lymphoma: FDG and Beyond

Lymphoma is one of the most common cancers worldwide, categorized into Hodgkin lymphoma and non-Hodgkin lymphoma. 18F-fluorodeoxyglucose positron emission tomography (FDG PET) has become an essential imaging tool for evaluating patients with lymphoma in terms of initial diagnosis, staging, prognosis, and treatment response assessment. Recent advancements in imaging technology and methodologies, along with the development of artificial intelligence, have revolutionized the evaluation of complex imaging data, enhancing the diagnostic and predictive power of PET in lymphoma. However, FDG is not cancer-specific, but it primarily reflects glucose metabolism, which has prompted the investigation of alternative PET tracers to address this limitation. Novel PET radiotracers, such as fibroblast activation protein inhibitors targeting the tumor microenvironment, have recently shown promising results in evaluating various malignancies compared to FDG PET. Furthermore, with the rapid advancements in immunotherapy and the favorable imaging properties of 89Zr, immunoPET has emerged as a promising modality, offering insights into the functional and molecular status of the immune system. ImmunoPET can also facilitate the development of new antibody therapeutics and radioimmunotherapy by providing pharmacokinetic and pharmacodynamic data. This review provides comprehensive insights into the current clinical applications of FDG PET in lymphoma, while also exploring novel PET imaging radiotracers beyond FDG, discussing their mechanisms of action and potential impact on patient management.

Carfilzomib, lenalidomide, dexamethasone (KRD) in BTKi relapsed or refractory mantle cell lymphoma: A phase II study from Fondazione Italiana Linfomi

Mantle cell lymphoma (MCL) is a rare lymphoproliferative neoplasm considered incurable, with a median survival of 3-5 years. In recent years, Bruton's tyrosine kinase inhibitors (BTKi) have been introduced, demonstrating high therapeutic activity. However, the prognosis for MCL patients failing ibrutinib therapy is particularly poor, with a survival expectation of a few months. In this phase II trial, we assessed the efficacy and safety of the carfilzomib-lenalidomide-dexamethasone (KRD) combination in MCL patients who were relapsed/refractory (R/R) or intolerant to BTKi and in need of treatment. The primary objective of the study was to evaluate the antitumor efficacy of the KRD combination in terms of 12-month overall survival (12-month OS). From September 2019 to December 2020, 16 patients were enrolled from 11 Italian centers. After a median follow-up of 2.37 months (95% CI 0.92-6.47), the 12-month OS was 13%. The rate of grade 3-4 adverse events (AEs) was 35%, and the overall response rate (ORR) was 19%. These results led to the premature termination of enrollment, as defined in the protocol stopping rules. The efficacy of the KRD combination in advanced-stage MCL patients who are R/R to BTKi is unsatisfactory and too toxic.

The rules of T-cell engagement: current state of CAR T cells and bispecific antibodies in B-cell lymphomas

ABSTRACT

T-cell engaging-therapies have transformed the treatment landscape of relapsed and refractory B-cell non-Hodgkin lymphomas by offering highly effective treatments for patients with historically limited therapeutic options. This review focuses on the advances in chimeric antigen receptor-modified T cells and bispecific antibodies, first providing an overview of each product type, followed by exploring the primary data for currently available products in large B-cell lymphoma, follicular lymphoma, and mantle cell lymphoma. This review also highlights key logistical and sequencing considerations across diseases and product types that can affect clinical decision-making.

Immunomodulatory drugs: a promising clinical ally for cancer immunotherapy

While immunomodulatory imide drugs (IMiDs) have been authorised for treatment of haematological cancers for over two decades, the appreciation of their ability to stimulate antitumour T cell and natural killer (NK) cell responses is relatively recent. Clinical trial data increasingly show that targeted immunotherapies, such as antibodies, T cells, and vaccines, improve outcomes when delivered in combination with the IMiD derivatives lenalidomide or pomalidomide. Here, we review these clinical data to highlight the relevance of IMiDs in combinatorial immunotherapy for both haematological and solid tumours. Further research into the molecular mechanisms of IMiDs and an increased understanding of their immunomodulatory effects may refine the specific applications of IMiDs and improve the design of future clinical trials, moving IMiDs to the forefront of combinatorial cancer immunotherapy.

SOHO State of the Art Updates and Next Questions: Treatment Evolution of Mantle Cell Lymphoma: Navigating the Different Entities and Biological Heterogeneity of Mantle Cell Lymphoma in 2024

Progress in mantle cell lymphoma (MCL) has led to significant improvement in outcomes of patients even in the real world (RW) setting albeit to a lesser degree. In parallel to the demonstration of benefit using combination therapy with rituximab plus high-dose cytarabine (R-AraC) as well as dose intensive therapy-autologous stem cell transplantation (DIT-ASCT) consolidation and maintenance, it became clear over the last 2 decades that MCL is a highly heterogenous disease at the molecular level, explaining differences observed in clinical behavior and response to therapy. While clinical prognostic factors and models have helped stratify patients with distinct outcomes, they failed to help guide therapy. The identification of molecular high-risk (HR) features, in particular, but not only, p53 aberrations (including mutations and deletions [del]), as well as complex karyotype (CK), has allowed to identify subsets of patients with poorer outcomes (median overall survival [OS] <2 years) regardless of conventional therapies used. The constant pattern of relapse seen in MCL has fueled sustained and productive efforts, with 7 novel agents approved in the United States (US), showing high and durable efficacy even in HR and chemo-refractory patients and likely curing a subset of patients in the relapsed or refractory (R/R) setting. Progress in diagnostics, in particular next-generation sequencing (NGS), which is accessible in routine practice nowadays, can help recognize patients with HR features, well beyond MIPI or Ki-67 prognostication, although the impact on decision making is still unclear. The era of integrating novel agents into our prior standard of care (SOC) has begun with a confirmed benefit, for example, ibrutinib (Ib) in the TRIANGLE study, defining the first new potential SOC in younger patients in over 30 years. Expanding on novel agents, either in combination, sequentially or to replace chemotherapy altogether, using biological doublets or triplets has led to a median progression-free survival (PFS) in excess of 72 months, certainly competitive with prior SOC and will continue to reshape the management of MCL patients. Achieving minimal residual disease negative (MRD-ve) status is becoming a new endpoint in MCL, and customizing maintenance and/or de-escalation/consolidation strategies is within reach, although it will require prospective, built-in MRD-based approaches, with the goal of eliminating subclinical disease and not simply delaying time to relapse. Taking into account the biological diversity of MCL is now feasible in routine clinical practice and has already helped recognize what not to do for HR patients (i.e., avoid intensive induction chemotherapy and/or ASCT for p53 mutated patients) as well as identify promising novel options. Ongoing and future work will help expand on these dedicated approaches, to further improve the management and outcomes of all MCL patients.

Biological and clinical determinants shaping heterogeneity in mantle cell lymphoma

ABSTRACT

Mantle cell lymphoma (MCL) is an uncommon mature B-cell lymphoma that presents a clinical spectrum ranging from indolent to aggressive disease, with challenges in disease management and prognostication. MCL is characterized by significant genomic instability, affecting various cellular processes, including cell cycle regulation, cell survival, DNA damage response and telomere maintenance, NOTCH and NF-κB/ B-cell receptor pathways, and chromatin modification. Recent molecular and next-generation sequencing studies unveiled a broad genetic diversity among the 2 molecular subsets, conventional MCL (cMCL) and leukemic nonnodal MCL (nnMCL), which may partially explain their clinical heterogeneity. Some asymptomatic and genetically stable nnMCL not requiring treatment at diagnosis may eventually progress clinically. Overall, the high proliferation of tumor cells, blastoid morphology, TP53 and/or CDKN2A/B inactivation, and high genetic complexity influence treatment outcome in cases treated with standard regimens. Emerging targeted and immunotherapeutic strategies are promising for refractory or relapsed cases and a few genetic and nongenetic determinants of refractoriness have been reported. This review summarizes the recent advances in MCL biology, focusing on molecular insights, prognostic markers, and novel therapeutic approaches.

Targeted Therapies in the Treatment of Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare, heterogeneous B-cell non-Hodgkin's lymphoma. The standard front-line treatment utilizes chemotherapy, often followed by consolidation with an autologous hematopoietic cell transplant; however, in most patients, the lymphoma will recur and require subsequent treatments. Additionally, mantle cell lymphoma primarily affects older patients and is frequently chemotherapy-resistant, which has further fostered the necessity for new, chemotherapy-free treatment options. In the past decade, targeted therapies in mantle cell lymphoma have been practice-changing as the treatment paradigm shifts further away from relying primarily on cytotoxic agents. Here, we will review the pathophysiology of mantle cell lymphoma and discuss the emergence of targeted, chemotherapy-free treatments aimed at disrupting the abnormal biology driving its lymphomagenesis. Treatments targeting the constitutive activation of NF-kB, Bruton's Tyrosine Kinase signaling, and anti-apoptosis will be the primary focus as we discuss their clinical data and toxicities. Our review will also focus primarily on the emergence and use of targeted therapies in the relapsed/refractory setting but will also discuss the emergence of their use in front-line therapy and in combination with other agents.

Novel treatment for mantle cell lymphoma - impact of BTK inhibitors and beyond

Mantle cell lymphoma (MCL) primarily affects older adults, accounting for 3-10% of all non-Hodgkin lymphoma (NHL) in western countries. The disease course of MCL is heterogenous; driven by clinical, cytogenetics, and molecular features that shape differences in outcomes, including proliferation index, MIPI scores, and mutational profile such as TP53 aberration. The advent of novel agents has fundamentally evolved the treatment landscape for MCL with treatment strategies that can now be more effectively tailored based on both patient- and disease-specific factors. In this review, we discuss the major classes of novel agents used for the treatment of MCL, focusing on efficacy and notable toxicities of BTK inhibitors. We further examine effective novel combination regimens and, lastly, discuss future directions for the evolution of targeted approaches for the treatment of MCL.

Recent advances in genomics and therapeutics in mantle cell lymphoma

Over the past decades, significant strides have been made in understanding the pathobiology, prognosis, and treatment options for mantle cell lymphoma (MCL). The heterogeneity observed in MCL's biology, genomics, and clinical manifestations, including indolent and aggressive forms, is intricately linked to factors such as the mutational status of the variable region of the immunoglobulin heavy chain gene, epigenetic profiling, and Sox11 expression. Several intriguing subtypes of MCL, such as Cyclin D1-negative MCL, in situ mantle cell neoplasm, CCND1/IGH FISH-negative MCL, and the impact of karyotypic complexity on prognosis, have been explored. Notably, recent immunochemotherapy regimens have yielded long-lasting remissions in select patients. The therapeutic landscape for MCL is continuously evolving, with a shift towards nonchemotherapeutic agents like ibrutinib, acalabrutinib, and venetoclax. The introduction of BTK inhibitors has brought about a transformative change in MCL treatment. Nevertheless, the challenge of resistance to BTK inhibitors persists, prompting ongoing efforts to discover strategies for overcoming this resistance. These strategies encompass non-covalent BTK inhibitors, immunomodulatory agents, BCL2 inhibitors, and CAR-T cell therapy, either as standalone treatments or in combination regimens. Furthermore, developing novel drugs holds promise for further improving the survival of patients with relapsed or refractory MCL. In this comprehensive review, we methodically encapsulate MCL's clinical and pathological attributes and the factors influencing prognosis. We also undertake an in-depth examination of stratified treatment alternatives. We investigate conceivable resistance mechanisms in MCL from a genetic standpoint and offer precise insights into various therapeutic approaches for relapsed or refractory MCL.

Phase 1b dose-finding study of rituximab, lenalidomide, and ibrutinib (R2I) in patients with relapsed/refractory mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare non-Hodgkin lymphoma that frequently becomes chemoresistant over time. The distinct mechanisms of ibrutinib and lenalidomide provided a judicious rationale to explore the combination with anti-CD20 immunotherapy. In this phase 1b study (NCT02446236), patients (n = 25) with relapsed/refractory MCL received rituximab with escalating doses of lenalidomide (days 1-21) and ibrutinib 560 mg (days 1-28) of 28-day cycles. The MTD for lenalidomide was 20 mg; most common grade ≥3 adverse events were skin rashes (32%) and neutropenic fever (24%). The best ORR was 88%, CR rate was 83%, and median duration of response (DOR) was 36.92 months (95% CI 33.77, 51.37). Responses were seen even in refractory patients or with high-risk features (e.g. blastoid variant, TP53 mutation, Ki-67 > 30%). R2I was safe and tolerable in patients with R/R MCL.

The story of the development of generic lenalidomide: How one company thwarted the Hatch-Waxman Act to generate billions of dollars in revenue

Lenalidomide (Revlimid®) was originally approved by the Food and Drug Administration (FDA) in 2005, however, a generic version was not available until 2022. In that time, the price of lenalidomide has increased more than 20 times, and in 2021 alone, it accounted for >$5.8 billion dollars in Medicare Part D spending. This was a direct consequence of legal tactics employed by the manufacturer to thwart development of generic formulations of lenalidomide. In this report, we review the clinical development of lenalidomide, provide background on generic drug manufacturing in the United States (US), describe the steps that the manufacturer took to prevent entry of generic lenalidomide into the US market, and advocate for legislative reform of the FDA approval process and patent law protections in the US.

Nine-year follow-up of lenalidomide plus rituximab as initial treatment for mantle cell lymphoma

Although chemoimmunotherapy is the current standard of care for initial treatment of mantle cell lymphoma (MCL), newer data suggest that there may be a role for a chemotherapy-free approach. We report the 9-year follow-up results of a multicenter, phase 2 study of lenalidomide plus rituximab (LR) as the initial treatment of MCL. The LR doublet is used as induction and maintenance until progression, with optional discontinuation after 3 years. We previously reported an overall response rate of 92% in evaluable patients, with 64% achieving a complete response. At a median follow-up of 103 months, 17 of 36 evaluable patients (47%) remain in remission. The 9-year progression-free survival and overall survival were 51% and 66%, respectively. During maintenance, hematologic adverse events included asymptomatic grade 3 or 4 cytopenia (42% neutropenia, 5% thrombocytopenia, and 3% anemia) and mostly grade 1 to 2 infections managed in the outpatient setting (50% upper respiratory infections, 21% urinary tract infections, 16% sinusitis, 16% cellulitis, and 13% pneumonia, with 5% requiring hospitalization). More patients developed grade 1 and 2 neuropathy during maintenance therapy (29%) than during induction therapy (8%). Twenty-one percent of patients developed secondary malignancies, including 5% with invasive malignancies, whereas the remainder were noninvasive skin cancers treated with local skin-directed therapy. Two patients permanently discontinued therapy because of concerns of immunosuppression during the COVID-19 pandemic. With long-term follow-up, LR continues to demonstrate prolonged, durable responses with manageable safety as initial induction therapy. This trial was registered at www.clinicaltrials.gov as #NCT01472562.

The shifting therapeutic paradigm for relapsed/refractory mantle cell lymphoma

Mantle cell lymphoma (MCL) is a heterogeneous subtype of non-Hodgkin lymphoma that has been historically associated with poor 5-year overall survival rates, especially for aggressive variants. Traditional cytotoxic chemotherapy had been a mainstay of therapy for relapsed/refractory (R/R) MCL for many years until the advent of molecularly targeted therapies and cell-based approaches. However, a significant concern is the lack of definitive consensus guidelines for management of R/R MCL. The managerial conundrum partly stems from the absence of head-to-head comparisons of novel therapies, with conclusions drawn from cross-trial comparisons. In this evidence-based review, we discuss the current therapeutic options for R/R MCL, including the most recent data from the BRUIN study that led to the approval of the first-in-class non-covalent reversible Bruton's tyrosine kinase (BTK) inhibitor pirtobrutinib in 2023, as well as the recent removal of ibrutinib from the market. We discuss outlooks for targeted therapy and tolerability considerations for novel agents, including unique considerations for the elderly population. We highlight emerging data that support the curative potential of chimeric antigen receptor-T (CAR-T) therapy from ZUMA-2, relative to other promising investigational agents in the pipeline, including glofitamab, epcoritamab, and zilovertamab vedotin. We summarize management recommendations based upon the most rigorous clinical evidence to date.

Chinese expert consensus on Bruton tyrosine kinase inhibitors in the treatment of B-cell malignancies

Targeted therapy with Bruton tyrosine kinase (BTK) inhibitors have revolutionized the treatment of patients with various B-cell malignancies. BTK inhibitors such as ibrutinib, zanubrutinib, orelabrutinib, and acalabrutinib have shown good clinical efficacy and better safety profiles than those of traditional chemotherapy and chemoimmunotherapy regimens. Multiple studies on new BTK inhibitors are ongoing, which may provide more therapeutic options for the treatment of B-cell malignancies. Considering the unmet need of evidence on BTK inhibitors in all clinical settings and to standardize the use of BTK inhibitors available in mainland China, Taiwan, Hong Kong, and Macau regions, this consensus has been formulated for the treatment of various B-cell malignancies based on the clinical practice and available evidences on the use of BTK inhibitors. The recommendations of this consensus will provide guidance to physicians and clinical researchers on the effective treatment of B-cell malignancies with BTK inhibitors.

Treatment of older patients with mantle cell lymphoma in the era of novel agents

Mantle cell lymphoma (MCL) is a rare, B-cell non-Hodgkin's lymphoma with a highly heterogeneous presentation that ranges from an indolent disease to an extremely aggressive one. Several clinical and biological prognostic markers can assist in determining the aggressiveness of the disease. Such as MIPI, Ki-67, and TP53, NOTCH1, and CDKN2A mutations. While aggressive chemoimmunotherapy regimens combining rituximab and cytarabine, followed by autologous stem-cell transplantation yield the most promising results, this treatment is too toxic for older patients. Several lower-intensity regimens have shown efficacy in older patients with reduced toxicity profiles. However, older relapsed/refractory patients have an extremely poor outcome. In the last several years, there is a major trend toward chemotherapy-free regimens, targeted therapies such as BTK, BCL-2 and PI3K inhibitors, and immunotherapies such as lenalidomide and CAR-T, which can provide a promising strategy for older patients. Herein we review the current therapies for older MCL patients, chemotherapy regimens, targeted therapies, and immunotherapies.

Beyond Bruton's tyrosine kinase inhibitors in mantle cell lymphoma: bispecific antibodies, antibody-drug conjugates, CAR T-cells, and novel agents

Mantle cell lymphoma is a B cell non-Hodgkin lymphoma (NHL), representing 2-6% of all NHLs and characterized by overexpression of cyclin D1. The last decade has seen the development of many novel treatment approaches in MCL, most notably the class of Bruton's tyrosine kinase inhibitors (BTKi). BTKi has shown excellent outcomes for patients with relapsed or refractory MCL and is now being studied in the first-line setting. However, patients eventually progress on BTKi due to the development of resistance. Additionally, there is an alteration in the tumor microenvironment in these patients with varying biological and therapeutic implications. Hence, it is necessary to explore novel therapeutic strategies that can be effective in those who progressed on BTKi or potentially circumvent resistance. In this review, we provide a brief overview of BTKi, then discuss the various mechanisms of BTK resistance including the role of genetic alteration, cancer stem cells, tumor microenvironment, and adaptive reprogramming bypassing the effect of BTK inhibition, and then provide a comprehensive review of current and emerging therapeutic options beyond BTKi including novel agents, CAR T cells, bispecific antibodies, and antibody-drug conjugates.

Adding venetoclax to lenalidomide and rituximab is safe and effective in patients with untreated mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare, incurable hematological malignancy with a heterogeneous presentation and clinical course. A wide variety of chemotherapy-based regimens are currently used in patients who are untreated. Over the last several years, several targeted or small-molecule therapies have shown efficacy in the relapsed/refractory setting and have since been explored in the frontline setting. Lenalidomide plus rituximab was explored in a phase 2 study of 38 patients with MCL who were untreated and ineligible to receive transplantation, in which the combination produced durable remissions. We looked to build upon this regimen by adding venetoclax to the combination. We conducted a multicenter, open-label, nonrandomized, single-arm study to evaluate this combination. We enrolled 28 unselected patients with untreated disease irrespective of age, fitness, or risk factors. Lenalidomide was dosed at 20 mg daily from days 1 to 21 of each 28-day cycle. The dose of venetoclax was determined using the time-to-event continual reassessment method. Rituximab was dosed at 375 mg/m2 weekly, starting on cycle 1, day 1 until cycle 2, day 1. No dose-limiting toxicities were noted. All patients were treated with venetoclax at the maximum tolerated dose of 400 mg daily. The most common adverse events were neutropenia and thrombocytopenia. The overall and complete response rates were 96% and 86%, respectively. In total, 86% of patients achieved minimal residual disease undetectability via next-generation sequencing. The median overall and progression-free survivals were not reached. The combination of lenalidomide, rituximab, and venetoclax is a safe and effective regimen in patients with untreated MCL. This trial was registered at www.clinicaltrials.gov as #NCT03523975.

Health resource utilization and costs of care for adult patients with relapsed or refractory mantle cell lymphoma in the United States: a retrospective claims analysis

OBJECTIVES

We assessed real-world healthcare resource utilization (HRU) and costs among US patients with relapsed or refractory mantle cell lymphoma (R/R MCL) by line of therapy (LoT).

METHODS

We selected patients from MarketScan® (1/1/2016-12/31/2020): ≥1 claims of MCL-indicated first line (1L) therapies, ≥1 diagnoses of MCL pre-index date (1L initiation date), ≥6-month continuous enrollment pre-index date, second line (2L) therapy initiation, ≥18 years old at 2L, and no clinical trial enrollment. Outcomes included time to next treatment (TTNT), all-cause HRU, and costs.

RESULTS

The cohort (N = 142) was 77.5% male, aged 62 years (median). Sixty-six percent and 23% advanced to 3L and 4L+, respectively. Mean (median) TTNT was 9.7 (5.9), 9.3 (5.0), and 6.3 (4.2) months for 2L, 3L, and 4L+, respectively. Mean (median) per patient per month (PPPM) costs were $29,999 ($21,313), $29,352 ($20,033), and $30,633 ($23,662) for 2L, 3L, and 4L+, respectively. Among those who received Bruton tyrosine kinase inhibitors, mean (median) PPPM costs were $24,702 ($17,203), $31,801 ($20,363), and $36,710 ($25,899) for 2L, 3L, and 4L+, respectively.

CONCLUSIONS

During the period ending in 2020, patients relapsed frequently, incurring high HRU and costs across LoTs. More effective treatments with long-lasting remissions in R/R MCL may reduce healthcare burden.

Treatment approaches for patients with TP53-mutated mantle cell lymphoma

Mantle cell lymphoma is an uncommon subtype of lymphoma characterised by clinical and biological heterogeneity. Although most patients with mantle cell lymphoma have durable responses after chemoimmunotherapy, there is a need to prospectively identify high-risk subsets of patients for whom disease control with standard chemotherapy will be short lived. Among the available prognostic factors, TP53 mutations are uniquely informative owing to their strong association with early disease progression and death among patients receiving conventional chemoimmunotherapy, with the highest negative prognostic value compared with other established risk indicators, including the mantle cell lymphoma international prognostic index, histological features, elevated Ki-67, and other genetic lesions. The poor outcomes for patients with TP53-mutated mantle cell lymphoma receiving chemoimmunotherapy and second-line Bruton tyrosine kinase inhibitors represent an urgent need for alternative approaches. In this Review, we synthesise the available data to inform the management of this high-risk subset of patients and present a treatment strategy prioritising clinical trials and early use of cellular therapies.

A FOXO1-dependent transcription network is a targetable vulnerability of mantle cell lymphomas

Targeting lineage-defined transcriptional dependencies has emerged as an effective therapeutic strategy in cancer treatment. Through screening for molecular vulnerabilities of mantle cell lymphoma (MCL), we identified a set of transcription factors (TFs) including FOXO1, EBF1, PAX5, and IRF4 that are essential for MCL propagation. Integrated chromatin immunoprecipitation and sequencing (ChIP-Seq) with transcriptional network reconstruction analysis revealed FOXO1 as a master regulator that acts upstream in the regulatory TF hierarchy. FOXO1 is both necessary and sufficient to drive MCL lineage commitment through supporting the lineage-specific transcription programs. We further show that FOXO1, but not its close paralog FOXO3, can reprogram myeloid leukemia cells and induce B-lineage gene expression. Finally, we demonstrate that cpd10, a small molecule identified from an enriched FOXO1 inhibitor library, induces a robust cytotoxic response in MCL cells in vitro and suppresses MCL progression in vivo. Our findings establish FOXO1 inhibition as a therapeutic strategy targeting lineage-driven transcriptional addiction in MCL.

The Serum- and Glucocorticoid-Inducible Kinase 1 (SGK1) as a Novel Therapeutic Target in Mantle Cell Lymphoma

INTRODUCTION

Mantle cell lymphoma (MCL) is an aggressive and incurable B-cell-derived malignant disease. MCL is treated using general chemotherapy; however, disease progression and relapse are common; thus, the development of novel therapeutic targets for treatment of MCL is urgently required. Serum- and glucocorticoid-inducible kinase 1 (SGK1) is involved in various cellular activities, and its dysregulation contributes to the pathogenesis of multiple types of cancer. However, little is known regarding its functional roles and associated molecular mechanisms in MCL.

METHODS

SGK1 inhibition mediated by either shRNA or treatment with SGK1 inhibitor (GSK650394) was conducted in MCL cell lines. Western blotting analysis was performed to figure out the expression of related proteins. MCL-cell-derived xenograft models were constructed to evaluate the anti-tumor effects of SGK1 inhibition or/and Bruton's tyrosine kinase (BTK) inhibition in vivo.

RESULTS

In this study, it was shown that inhibition of SGK1 significantly reduced cell proliferation, invasion and migration, increased apoptosis and blocked cell cycle progression in MCL cells. Furthermore, SGK1 inhibition significantly reduced the activation of ERK, AKT/mTOR, JAK2/STAT3 and the NF-κB signaling pathways. Using MCL-cell-derived xenograft mice models, SGK1 inhibition decreased tumor cell proliferation and tumor growth. Importantly, SGK1 overexpression significantly promoted xenograft tumor growth. Moreover, simultaneous inhibition of SGK1 and Bruton tyrosine kinase (BTK) resulted in synergistic anti-tumor effects on MCL both in vitro and in vivo.

CONCLUSION

SGK1 may be a novel candidate therapeutic target and simultaneous inhibition of SGK1 and BTK may be a promising therapeutic strategy for MCL patients. Further pre-clinical and even clinical studies of SGK1 inhibitor or combination with BTK inhibitor are essential.

What is the role of up-front autologous stem cell transplantation in mantle cell lymphoma?

Up-front autologous stem cell transplantation (ASCT) is the established standard of care for younger, transplant-eligible MCL patients and is associated with a prolonged progression-free survival (PFS) benefit. However, there is no randomized controlled trial data, with therapy including rituximab and cytarabine, that has established a PFS and overall survival (OS) benefit with ASCT in the modern era. Multiple retrospective studies have failed to identify an OS benefit associated with ASCT in younger MCL patients. The high-risk patient subgroup with evidence of baseline TP53 mutation has a dismal outcome with intensive chemoimmunotherapy followed by ASCT, thus up-front ASCT is not optimal for this patient subset. Ongoing randomized clinical trials will help to clarify the role of up-front ASCT in the future. For example, the ongoing European MCL Network Triangle study incorporating ibrutinib into chemoimmunotherapy induction and maintenance with and without ASCT will help define the role of ASCT in the era of novel biologically targeted agents (ClinicalTrials.gov identifier: NCT02858258). Additionally, minimal residual disease (MRD) assessment is a powerful prognostic tool in MCL, and the ongoing Eastern Cooperative Oncology Group-American College of Radiology Imaging Network E4151 study is comparing maintenance rituximab alone vs ASCT consolidation in MCL patients who achieve remission and MRD-undetectable status post induction (ClinicalTrials.gov identifier: NCT03267433). ASCT remains a highly efficacious initial therapy for younger MCL patients; however, ultimately the decision to pursue ASCT requires discussion of risks vs benefits, incorporating patient preferences and values.

Treatment Landscape of Relapsed/Refractory Mantle Cell Lymphoma: An Updated Review

Mantle cell lymphoma (MCL) accounts for nearly 2-6% of all non-Hodgkin lymphoma (NHL) cases, with a steady incidence increase over the past few decades. Although many patients achieve an adequate response to the upfront treatment, the short duration of remission with rapid relapse is challenging during MCL management. In this regard, there is no consensus on the best treatment options for relapsed/refractory (R/R) disease, and the international guidelines demonstrate wide variations in the recommended approaches. The last decade has witnessed the introduction of new agents in the treatment landscape of R/R MCL. Since the introduction of Bruton's tyrosine kinase (BTK) inhibitors, the treatment algorithm and response of R/R MCL patients have dramatically changed. Nevertheless, BTK resistance is common, necessitating further investigations to develop novel agents with a more durable response. Novel agents targeting the B-cell receptor (BCR) signaling have exhibited clinical activity and a well-tolerable safety profile. However, as the responses to these novel agents are still modest in most clinical trials, combination strategies were investigated in pre-clinical and early clinical settings to determine whether the combination of novel agents would exhibit a better durable response than single agents. In this report, we provide an updated literature review that covers recent clinical data about the safety and efficacy of novel therapies for the management of R/R MCL.

Reshaping the tumor microenvironment: The versatility of immunomodulatory drugs in B-cell neoplasms

Immunomodulatory drugs (IMiDs) such as thalidomide, lenalidomide and pomalidomide are antitumor compounds that have direct tumoricidal activity and indirect effects mediated by multiple types of immune cells in the tumor microenvironment (TME). IMiDs have shown remarkable therapeutic efficacy in a set of B-cell neoplasms including multiple myeloma, B-cell lymphomas and chronic lymphocytic leukemia. More recently, the advent of immunotherapy has revolutionized the treatment of these B-cell neoplasms. However, the success of immunotherapy is restrained by immunosuppressive signals and dysfunctional immune cells in the TME. Due to the pleiotropic immunobiological properties, IMiDs have shown to generate synergetic effects in preclinical models when combined with monoclonal antibodies, immune checkpoint inhibitors or CAR-T cell therapy, some of which were successfully translated to the clinic and lead to improved responses for both first-line and relapsed/refractory settings. Mechanistically, despite cereblon (CRBN), an E3 ubiquitin ligase, is considered as considered as the major molecular target responsible for the antineoplastic activities of IMiDs, the exact mechanisms of action for IMiDs-based TME re-education remain largely unknown. This review presents an overview of IMiDs in regulation of immune cell function and their utilization in potentiating efficacy of immunotherapies across multiple types of B-cell neoplasms.

SOHO State of the Art Updates and Next Questions: Managing Relapsed Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin lymphoma i.e., incurable with current therapies. While some patients experience prolonged remissions following initial therapy, most will have a relapsing-remitting course requiring several lines of treatment over the course of their disease. Several targeted therapies are now available to treat patients with relapsed MCL. The Bruton's tyrosine kinase (BTK) inhibitors, including ibrutinib, acalabrutinib, and zanubrutinib, are highly active in MCL and currently approved for treating patients with relapsed disease. Bortezomib and lenalidomide are available as monotherapy or in combination with other agents. Venetoclax is active and can be considered for use in relapsed MCL, although it is not currently approved by regulatory agencies. Chimeric antigen receptor T-cell (CAR-T) therapy with brexucabtagene autoleucel yields high response rates and is now approved for patients with relapsed MCL. Allogeneic stem cell transplant remains an option for a small subset of medically fit and motivated patients who have progressed through multiple lines of therapy, although its use is limited by substantial toxicity. There is currently no standard approach to sequencing therapies for patients with relapsed MCL, and the ability to utilize disease biologic and clinical characteristics to guide treatment decisions in this setting remains limited. In this review, we summarize the current evidence to guide the management of patients with relapsed MCL, review emerging agents and combination therapies that are under investigation, and outline our current treatment approach for these patients.

Mantle cell lymphoma: A clinical review of the changing treatment paradigms with the advent of novel therapies, and an insight into Indian data

BACKGROUND

Mantle cell lymphoma (MCL) is a rare type of mature B-cell lymphoid malignancy with the pathologic hallmark of translocation t(11;14) (q13, q32), which leads to an overexpression of Cyclin D1 (CCND1). The disease is also characterized by the presence of a high number of recurrent genetic alterations, which include aberrations in several cellular pathways. MCL is a heterogeneous disease with a wide range of clinical presentations and a majority presenting with aggressive disease in advanced stages.

RECENT FINDINGS

Management of MCL is bereft with challenges due to its resistant and relapsing pattern. Despite improvements in remission durations, the disease is currently incurable with standard therapy and has a median survival of about 3-5 years. The use of small molecules like the bruton tyrosine kinase (BTK) and BCL2 inhibitors, for treating relapsed MCL has been established leading to a diminishing role for conventional chemotherapy. Combinations of small molecule inhibitors with or without chemoimmunotherapy, are showing promising results. Cellular therapy in the form of CAR-T cell therapy, has been approved recently.

CONCLUSIONS

Personalized cancer treatment and chemo-free regimens are showing promise and results from well-planned long-term studies are evolving. In India, there is a paucity of epidemiological, clinical, and research data in this field.

Tumor Microenvironment and Immunotherapy-Based Approaches in Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin lymphoma (NHL) characterized by the translocation t(11;14) (q13;q32) and a poor response to rituximab–anthracycline-based chemotherapy. High-dose cytarabine-based regimens offer a durable response, but an important number of MCL patients are not eligible for intensive treatment and are ideal candidates for novel targeted therapies (such as BTK, proteasome or BCL2 inhibitors, Immunomodulatory Drugs (IMiDs), bispecific antibodies, or CAR-T cell therapy). On the bench side, several studies aiming to integrate the tumor within its ecosystem highlighted a critical role of the tumor microenvironment (TME) in the expansion and resistance of MCL. This led to important insights into the role of the TME in the management of MCL, including potential targets and biomarkers. Indeed, targeted agents often have a combined mechanism of action on the tumor B cell but also on the tumor microenvironment. The aim of this review is to briefly describe the current knowledge on the biology of the TME in MCL and expose the results of the different therapeutic strategies integrating the TME in this disease.

Mantle Cell Lymphoma: the Role of Risk-Adapted Therapy and Treatment of Relapsed Disease

PURPOSE OF REVIEW

In this review, the current treatment strategies are recapped, evolving agents are discussed, and we provide guidance in treating R/R MCL.

RECENT FINDINGS

There has been an advancement in treatment using targeted therapy, cellular therapies including chimeric antigen receptor (CAR) T cell therapy and hematopoietic stem cell transplantation (HSCT) and novel therapeutic agents including non-covalent BTKis, bispecific antibodies, and antibody-drug conjugates for treatment of refractory and relapsed mantle cell lymphoma. Mantle cell lymphoma (MCL) is a mature B-cell lymphoma that is associated with a poor prognosis. Current treatments include immunochemotherapy, chemotherapy and autologous stem cell transplantation (SCT) which place patients in remission but result in relapse. Chemoimmunotherapy uses chemotherapeutic agents paired with rituximab in patients who have chemo-sensitive disease with prolonged remission of at least > 2 years and/or have contraindications to chemotherapy that serve as bridges to more definitive treatment. Additional therapies including proteosome inhibitor-based therapies and immunomodulators, like bortezomib and lenalidomide, can be used as single agents or in combination with others. Bruton's tyrosine kinase (BTK) inhibitors including ibrutinib, acalaburtinib, and zanubrutinib have also been proven effective for the treatment of (R/R) disease. Another agent is Venetoclax, a robust drug that can be used in MCL after progression or intolerance to BTKi. Newer advances in the management of MCL have led to the utilization of cellular therapies including chimeric antigen receptor (CAR) T cell therapy and SCT that are options for healthy young (< 65 years old) who have progressed through several lines of therapies. With progression of disease, mutations are acquired that cause therapy resistance. Novel therapeutic agents such as non-covalent BTKis, bispecific antibodies, and antibody-drug conjugates are paving the way for advancements in treatment for R/R MCL. R/R MCL is a complex disease with many therapeutic options none of which has been proven superior in head-to-head comparison. In this review, the current treatment strategies are recapped, evolving agents are discussed, and we provide guidance in treating R/R MCL.

Oncological Treatment-Related Fatigue in Oncogeriatrics: A Scoping Review

Fatigue is a highly prevalent symptom in both cancer patients and the older population, and it contributes to quality-of-life impairment. Cancer treatment-related fatigue should thus be included in the risk/benefit assessment when introducing any treatment, but tools are lacking to a priori estimate such risk. This scoping review was designed to report the current evidence regarding the frequency of fatigue for the different treatment regimens proposed for the main cancer indications, with a specific focus on age-specific data, for the following tumors: breast, ovary, prostate, urothelium, colon, lung and lymphoma. Fatigue was most frequently reported using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) versions 3 to 5. A total of 324 regimens were analyzed; data on fatigue were available for 217 (67%) of them, and data specific to older patients were available for 35 (11%) of them; recent pivotal trials have generally reported more fatigue grades than older studies, illustrating increasing concern over time. This scoping review presents an easy-to-understand summary that is expected to provide helpful information for shared decisions with patients regarding the anticipation and prevention of fatigue during each cancer treatment.

Real-World Treatment Patterns and Outcomes of Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is considered incurable with the available chemoimmunotherapy approaches, and therefore newer, effective targeted therapies such as Bruton Tyrosine Kinase (BTK) inhibitors are increasingly used in MCL as chronic suppressive therapy, especially in the elderly. We aimed to describe the treatment patterns in MCL at different lines of therapy with a focus on BTK inhibitor use and compare outcomes with known prognostic factors using a nationwide Flatiron Health electronic health record (EHR)-derived de-identified database. We analyzed patient-level data from the period of 2011 to 2021. In this study of 4336 patients with MCL, we found that bendamustine plus rituximab chemotherapy was the most commonly used frontline regimen (42%). Maintenance rituximab or consolidative autologous stem cell transplant (ASCT) was administered to 31% of all patients. Also, for patients who received ASCT as consolidation therapy, only 34% subsequently received rituximab maintenance. BTK inhibitors were the most preferred agents in second or later lines of therapy (n=933, 57%), followed by bortezomib, lenalidomide, and venetoclax, respectively. Among patients treated with BTK inhibitors, the median real-world overall survival (rwOS) was 35 months (95%CI 27-50), 24 months (95%CI 22 - 30), and 18 months (95% CI 14 - 21), for first line, second line and for third or later line of therapy, respectively. Patients with deletion 17p/TP53 mutation and blastoid variant MCL had poor outcomes; however, BTK inhibitors appeared to mitigate the negative influence of del17p/TP53 mutated MCL with an HR of 1.17 (95%CI 0.88 - 1.55) on multivariable analysis.

Relapsed/Refractory Mantle Cell Lymphoma: Beyond BTK Inhibitors

Mantle cell lymphoma (MCL) is a rare mature B-cell non-Hodgkin lymphoma (B-NHL) with historically poor outcomes. Virtually all patients will eventually experience refractory or relapsed (R/R) disease, with a virulent course of resistance and serial relapses, making treatment challenging. The available therapies for R/R MCL are not curative with conventional therapy, their goal being to palliate and prolong survival. A variety of agents approved for R/R MCL, including Bruton's tyrosine kinase inhibitors (BTKi), changed the treatment landscape of R/R MCL. In the pre-BTKi era, the median progression-free survival (PFS) in R/R disease was 4-9 months. With the introduction of ibrutinib, the median PFS improved to 13-14.6 months. Despite these impressive results, the duration of response is limited, and resistance to BTKi inevitably develops in a subset of patients. Outcomes after progression on BTKi are extremely poor, with a median overall survival (OS) of 6 to 10 months. Certain therapies, such as chimeric antigen receptor (CAR) T cells, have shown promising results after BTKi failure. The preferred combination and sequencing of therapies beyond BTKi remain unestablished and are currently being investigated. In this review, we describe the current evidence for the available treatment of R/R MCL after progression on BTKi.

Mantle cell lymphoma management trends and novel agents: where are we going?

The heterogeneity in disease pathology, the unpredictability in disease prognosis, and the variability in response to therapy make mantle cell lymphoma (MCL) a focus of novel therapeutic development. MCL is characterized by dysregulated expression of cyclin D1 through a chromosome t(11;14) translocation. MCL international prognostic index (MIPI), ki-67 proliferation index, and TP53 mutation status are currently utilized for prognostication. With advances in pharmacokinetic analysis and drug discovery, treatment strategy has evolved from chemotherapy to combination of targeted, epigenetic, and immune therapies. In this review, we discuss investigational and newly approved treatment approaches. In a short time, the US Food and Drug Administration (FDA) has approved five agents for the treatment of MCL: lenalidomide, an immunomodulatory agent; bortezomib, a proteasome inhibitor; and ibrutinib, acalabrutinib, and zanubrutinib, all Bruton kinase inhibitors. Epigenetic agents (e.g. cladribine and vorinostat), mammalian target of rapamycin (mTOR) inhibitors (e.g. temsirolimus and everolimus), and monoclonal antibodies and/or antibody-drug conjugates (e.g. obinutuzumab, polatuzumab, and ublituximab) are promising therapeutic agents currently under clinical trial investigation. Most recently, chimeric antigen receptor (CAR)-T cell therapy and bispecific T-cell engager (BiTE) therapy even open a new venue for MCL treatment. However, due to its intricate pathology nature and high relapse incidence, there are still unmet needs in developing optimal therapeutic strategies for both frontline and relapsed/refractory settings. The ultimate goal is to develop innovative personalized combination therapy approaches for the purpose of delivering precision medicine to cure this disease.

Evolving frontline immunochemotherapy for mantle cell lymphoma and the impact on survival outcomes

Because there have been a dvances in frontline treatment for mantle cell lymphoma (MCL) over the last 2 decades, we sought to characterize the changes in frontline treatment patterns and their association with outcomes. Patients with newly diagnosed MCL from September 2002 through June 2015 were enrolled in a prospective cohort study, and clinical characteristics, treatment, and clinical outcomes were compared between patients diagnosed from 2002 to 2009 (Era 1) compared with 2010 to 2015 (Era 2). Patient age, sex, and simplified MCL International Prognostic Index (sMIPI) score were similar between the 2 groups. In patients age 65 years or younger, there was less use of rituximab plus hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (R-Hyper-CVAD) (16.1% vs 8.8%) but more use of rituximab plus maximum-strength cyclophosphamide, doxorubicin, vincristine, and prednisone (R-maxi-CHOP) alternating with rituximab plus high-dose cytarabine (R-HiDAC), also known as the Nordic regimen, and R-CHOP alternating with rituximab plus dexamethasone, high-dose cytarabine, and cisplatin (R-DHAP) (1.1% vs 26.4%) and less use of R-CHOP or R-CHOP-like regimens (64.5% vs 35.2%) but more use of R-bendamustine (0% vs 12.1%) in Era 2 (P < .001). These changes were associated with improved event-free survival (EFS; 5-year EFS, 34.3% vs 50.0%; P = .010) and overall survival (OS; 5-year OS, 68.8% vs 81.6%; P = .017) in Era 2. In patients older than age 65 years, there was less use of R-CHOP or R-CHOP-like therapy (39.0% vs 14.3%) and nonstandard systemic therapy (36.6% vs 13.0%) but more use of R-bendamustine (0% vs 49.4%). These changes were associated with a trend for improved EFS (5-year EFS, 25.4% vs 37.5%; P = .051) in Era 2. The shift from R-CHOP or R-CHOP-like regimens to R-bendamustine was associated with improved EFS (5-year EFS, 25.0% vs 44.6%; P = .008) in Era 2. Results from this prospective cohort study provide critical real-world evidence for improved outcomes with evolving frontline patterns of care in patients with MCL.

Regulation of B-Cell Receptor Signaling and Its Therapeutic Relevance in Aggressive B-Cell Lymphomas

The proliferation and survival signals emanating from the B-cell receptor (BCR) constitute a crucial aspect of mature lymphocyte's life. Dysregulated BCR signaling is considered a potent contributor to tumor survival in different subtypes of B-cell non-Hodgkin lymphomas (B-NHLs). In the last decade, the emergence of BCR-associated kinases as rational therapeutic targets has led to the development and approval of several small molecule inhibitors targeting either Bruton's tyrosine kinase (BTK), spleen tyrosine kinase (SYK), or phosphatidylinositol 3 kinase (PI3K), offering alternative treatment options to standard chemoimmunotherapy, and making some of these drugs valuable assets in the anti-lymphoma armamentarium. Despite their initial effectiveness, these precision medicine strategies are limited by primary resistance in aggressive B-cell lymphoma such as diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL), especially in the case of first generation BTK inhibitors. In these patients, BCR-targeting drugs often fail to produce durable responses, and nearly all cases eventually progress with a dismal outcome, due to secondary resistance. This review will discuss our current understanding of the role of antigen-dependent and antigen-independent BCR signaling in DLBCL and MCL and will cover both approved inhibitors and investigational molecules being evaluated in early preclinical studies. We will discuss how the mechanisms of action of these molecules, and their off/on-target effects can influence their effectiveness and lead to toxicity, and how our actual knowledge supports the development of more specific inhibitors and new, rationally based, combination therapies, for the management of MCL and DLBCL patients.

Sequencing of Novel Therapies for Mantle Cell Lymphoma

OPINION STATEMENT

There is no standard approach to sequencing novel therapies in mantle cell lymphoma (MCL). For initial treatment, intensive induction chemotherapy followed by autologous stem cell transplant and rituximab maintenance remains our preferred approach in young, fit patients. We consider bendamustine plus rituximab or lenalidomide plus rituximab in patients who are ineligible for intensive chemotherapy-based approaches. Bruton's tyrosine kinase inhibitors are our preferred class of agents to use in the second-line setting. When patients inevitably relapse on one of these agents, we proceed with chimeric antigen receptor T-cell (CAR T) therapy in eligible patients, often with the use of bridging therapy with corticosteroids, lenalidomide, or venetoclax. We treat patients who are ineligible for CAR T or clinic trial with venetoclax, lenalidomide, or proteosome inhibitor-based regimens, although efficacy is expected to be limited in this setting with a shortened duration of response to each subsequent line of therapy. Allogeneic stem cell transplant remains an option for carefully selected patients who progress after autologous stem cell transplant and CAR T. Clinical trials involving combinations of novel agents in early lines of therapy are ongoing, and new compounds with unique mechanisms of action are in development. The results of ongoing clinical trials with novel agents will further change the treatment landscape for patients with MCL in the coming years.

Outcomes and Utilization Trends of Front-Line Autologous Hematopoietic Cell Transplantation for Mantle Cell Lymphoma

Although autologous hematopoietic cell transplantation (auto-HCT) has become a common practice for eligible patients in the front-line setting with mantle cell lymphoma (MCL), there are limited data regarding trends in auto-HCT utilization and associated outcomes. This study used the Center for International Blood and Marrow Transplant Research (CIBMTR) database to evaluate survival outcomes and auto-HCT utilization in adults age ≥18 years who underwent auto-HCT within 12 months of diagnosis of MCL between January 2000 and December 2018. The 19-year period from 2000 to 2018 was divided into 4 separate intervals-2000 to 2004, 2005 to 2009, 2010 to 2014, and 2015 to 2018-and encompassed 5082 patients. To evaluate transplantation utilization patterns, we combined MCL incidence derived from the SEER 21 database with CIBMTR- reported auto-HCT activity within 12 months of diagnosis of MCL. Primary outcomes included overall survival (OS) along with the auto-HCT utilization rate. The cumulative incidence of nonrelapse mortality at 1 year decreased from 7% in the earliest cohort (2000 to 2004) to 2% in the latest cohort (2015 to 2018). Mirroring this trend, OS outcomes improved continually with time, with a 3-year OS of 72% in the earliest cohort improving to 86% in the latest cohort. In addition, we noted an increase in auto-HCT utilization from 2001 to 2018, particularly in patients age ≤65 years. This large retrospective analysis highlights trends in auto-HCT utilization and outcomes in patients with MCL and emphasizes the need to optimize pretransplantation and post-transplantation treatment strategies to enhance survival outcomes.

Zanubrutinib monotherapy in relapsed/refractory mantle cell lymphoma: a pooled analysis of two clinical trials

Mantle cell lymphoma (MCL) is a mature B-cell neoplasm with a high initial response rate followed almost invariably by relapse. Here we report the pooled data from 2 studies, BGB-3111-AU-003 and BGB-3111-206, to explore the efficacy of zanubrutinib monotherapy in relapsed/refractory (R/R) MCL. A total of 112 patients were included. Median follow-up durations were 24.7 and 24.9 months for BGB-3111-AU-003 and BGB-3111-206, respectively. Overall response rate (ORR) and complete response (CR) rate were 84.8% and 62.5%, and median duration of response, progression-free survival (PFS) and overall survival (OS) were 24.9, 25.8 and 38.2 months, respectively. After weighting, the PFS (median: NE vs. 21.1 months, P = 0.235) and OS (median: NE vs. 38.2 months, P = 0.057) were similar but numerically better in the second-line than later-line group. Zanubrutinib was well-tolerated with treatment discontinuation and dose reduction for adverse events in 12.5% and 2.7% of patients, respectively. Hypertension, major hemorrhage and atrial fibrillation/flutter rates were 11.6%, 5.4% and 1.8%, respectively. Zanubrutinib is efficacious in R/R MCL, with a favorable safety profile.

Non-chemotherapy Options for Newly Diagnosed Mantle Cell Lymphoma

OPINION STATEMENT

Mantle cell lymphoma is a rare and incurable non-Hodgkin lymphoma with a heterogenous clinical presentation. Typically, treatment consists of frontline chemoimmunotherapy induction with or without autologous stem cell transplant (ASCT) as consolidation. However, this approach has the propensity to increase short- and long-term toxicities, such as secondary malignancies, without being curative. Genomic profiling of MCL will allow for greater impact of new targeted therapies in the future and may become a helpful tool to guide treatment. Based on the data discussed, use of non-chemotherapy options may become the preferred approach for frontline therapy as opposed to conventional chemotherapy and hematopoietic stem cell transplants.

Immunomodulatory Drugs for the Treatment of B Cell Malignancies

Accumulating evidence suggests that the tumor microenvironment (TME) is involved in disease progression and drug resistance in B cell malignancies, by supporting tumor growth and facilitating the ability of malignant cells to avoid immune recognition. Immunomodulatory drugs (IMiDs) such as lenalidomide have some direct anti-tumor activity, but critically also target various cellular compartments of the TME including T cells, NK cells, and stromal cells, which interfere with pro-tumor signaling while activating anti-tumor immune responses. Lenalidomide has delivered favorable clinical outcomes as a single-agent, and in combination therapy leads to durable responses in chronic lymphocytic leukemia (CLL) and several non-Hodgkin lymphomas (NHLs) including follicular lymphoma (FL), diffuse large B cell lymphoma (DLBCL), and mantle cell lymphoma (MCL). Recently, avadomide, a next generation cereblon E3 ligase modulator (CELMoD), has shown potent anti-tumor and TME immunomodulatory effects, as well as promising clinical efficacy in DLBCL. This review describes how the pleiotropic effects of IMiDs and CELMoDs could make them excellent candidates for combination therapy in the immuno-oncology era-a concept supported by preclinical data, as well as the recent approval of lenalidomide in combination with rituximab for the treatment of relapsed/refractory (R/R) FL.

Brexucabtagene Autoleucel: A Novel Chimeric Antigen Receptor T-cell Therapy for the Treatment of Mantle Cell Lymphoma

OBJECTIVE

To identify and assess the current literature surrounding the safety, efficacy, and practical considerations of brexucabtagene autoleucel (brexu-cel) for the treatment of relapsed or refractory (r/r) mantle cell lymphoma (MCL).

DATA SOURCES

An English-based literature search was conducted using the terms "brexucabtagene autoleucel" AND "mantle cell lymphoma" OR "KTE-X19"in PubMed (inception through May 1, 2021), EMBASE (inception through May 1, 2021), and ClinicalTrials.gov.

STUDY SELECTION AND DATA EXTRACTION

All studies evaluating the use of brexu-cel in MCL were considered for inclusion.

DATA SYNTHESIS

In the pivotal ZUMA-2 trial, brexu-cel demonstrated objective response and complete response rates of 85% and 59%, respectively. These results were consistent among high-risk subgroups. Noteworthy treatment-related adverse effects included grade ≥3 cytopenias (94%), immune effector cell-associated neurotoxicity syndrome (31%), and cytokine release syndrome (15%). Brexu-cel elicited a toxicity profile similar to that of other novel chimeric antigen receptor (CAR) T-cell products, with no new safety signals.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

There are currently no head-to-head clinical trials evaluating brexu-cel against other approved subsequent-line options in r/r MCL. In a relatively small phase II trial, brexu-cel demonstrated impressive response rates in heavily pretreated patients, with few viable alternatives. Long-term safety and efficacy outcomes with brexu-cel are unknown. The prevention, identification, and management of unique CAR T-cell toxicities requires expert care from a well-trained interdisciplinary team.

CONCLUSION

Brexu-cel has emerged as a viable treatment option in MCL. Additional studies are required to determine the optimal sequencing and place in therapy for brexu-cel in this highly heterogeneous, pathobiologically distinct, and incurable malignancy.

Cancer therapies based on targeted protein degradation - lessons learned with lenalidomide

For decades, anticancer targeted therapies have been designed to inhibit kinases or other enzyme classes and have profoundly benefited many patients. However, novel approaches are required to target transcription factors, scaffolding proteins and other proteins central to cancer biology that typically lack catalytic activity and have remained mostly recalcitrant to drug development. The selective degradation of target proteins is an attractive approach to expand the druggable proteome, and the selective oestrogen receptor degrader fulvestrant served as an early example of this concept. Following a long and tragic history in the clinic, the immunomodulatory imide drug (IMiD) thalidomide was discovered to exert its therapeutic activity via a novel and unexpected mechanism of action: targeting proteins to an E3 ubiquitin ligase for subsequent proteasomal degradation. This discovery has paralleled and directly catalysed myriad breakthroughs in drug development, leading to the rapid maturation of generalizable chemical platforms for the targeted degradation of previously undruggable proteins. Decades of clinical experience have established front-line roles for thalidomide analogues, including lenalidomide and pomalidomide, in the treatment of haematological malignancies. With a new generation of 'degrader' drugs currently in development, this experience provides crucial insights into class-wide features of degraders, including a unique pharmacology, mechanisms of resistance and emerging therapeutic opportunities. Herein, we review these past experiences and discuss their application in the clinical development of novel degrader therapies.

Imaging Assessment of Tumor Response in the Era of Immunotherapy

Assessment of tumor response during treatment is one of the most important purposes of imaging. Before the appearance of immunotherapy, response evaluation criteria in solid tumors (RECIST) and positron emission tomography response criteria in solid tumors (PERCIST) were, respectively, the established morphologic and metabolic response criteria, and cessation of treatment was recommended when progressive disease was detected according to these criteria. However, various types of immunotherapy have been developed over the past 20 years, which show novel false positive findings on images, as well as distinct response patterns from conventional therapies. Antitumor immune response itself causes 18F-fluorodeoxyglucose (FDG) uptake in tumor sites, known as "flare phenomenon", so that positron emission tomography using FDG can no longer accurately identify remaining tumors. Furthermore, tumors often initially increase, followed by stability or decrease resulting from immunotherapy, which is called "pseudoprogression", so that progressive disease cannot be confirmed by computed tomography or magnetic resonance imaging at a single time point. As a result, neither RECIST nor PERCIST can accurately predict the response to immunotherapy, and therefore several new response criteria fixed for immunotherapy have been proposed. However, these criteria are still controversial, and also require months for response confirmation. The establishment of optimal response criteria and the development of new imaging technologies other than FDG are therefore urgently needed. In this review, we summarize the false positive images and the revision of response criteria for each immunotherapy, in order to avoid discontinuation of a truly effective immunotherapy.

Mantle cell lymphoma - advances in molecular biology, prognostication and treatment approaches

Mantle cell lymphoma (MCL) is clinically characterised by its heterogenous behaviour with courses ranging from indolent cases that do not require therapy for years to highly aggressive MCL with a very limited prognosis. A better understanding of the complex biology of MCL has already led to the approval of several innovative agents, expanding the landscape of MCL therapies and improving therapeutic options especially for refractory/relapsed (R/R) disease. Nevertheless, to further optimise MCL treatment, early identification of individual risk profile and risk-adapted, patient-tailored choice of therapeutic strategy needs to be prospectively incorporated into clinical patient management. The present review highlights recent advances in deciphering the molecular background of MCL, the definition of prognostically relevant factors and the identification of potential druggable targets and summarises current treatment recommendations for primary and R/R MCL including novel targeted therapies.

Novel Treatments for Mantle Cell Lymphoma: From Targeted Therapies to CAR T Cells

Mantle cell lymphoma is a rare B-cell non-Hodgkin's lymphoma that retains a sobering prognosis despite an extensive research effort. Mantle cell lymphoma remains incurable even with aggressive, and at times toxic, chemoimmunotherapy with early incorporation of autologous stem cell transplantation. Given this, attention has turned to the use of targeted therapies addressing dysregulation of B-cell signaling pathways. Drugs such as immunomodulatory agents, proteasome inhibitors, and Bruton's tyrosine kinase inhibitors have shown success in the relapsed/refractory population, and there is ongoing investigation into the utilization of novel Bruton's tyrosine kinase, B-cell leukemia/lymphoma-2, and spleen tyrosine kinase inhibitors alone or in combination in both the front-line and relapsed settings. Other areas of research in novel immunotherapies include investigations of bispecific T-cell engagers and antibody-drug conjugates. Most recently, chimeric antigen receptor T-cell therapy has been granted US Food and Drug Administration approval as a result of durable remissions even in high-risk patients who have classically done poorly with traditional chemoimmunotherapy. The intent of this article is to review the literature describing these selective therapies and discuss their current and future roles in the treatment of mantle cell lymphoma.

Relapsed Mantle Cell Lymphoma: Current Management, Recent Progress, and Future Directions

The increasing number of approved therapies for relapsed mantle cell lymphoma (MCL) provides patients effective treatment options, with increasing complexity in prioritization and sequencing of these therapies. Chemo-immunotherapy remains widely used as frontline MCL treatment with multiple targeted therapies available for relapsed disease. The Bruton's tyrosine kinase inhibitors (BTKi) ibrutinib, acalabrutinib, and zanubrutinib achieve objective responses in the majority of patients as single agent therapy for relapsed MCL, but differ with regard to toxicity profile and dosing schedule. Lenalidomide and bortezomib are likewise approved for relapsed MCL and are active as monotherapy or in combination with other agents. Venetoclax has been used off-label for the treatment of relapsed and refractory MCL, however data are lacking regarding the efficacy of this approach particularly following BTKi treatment. Anti-CD19 chimeric antigen receptor T-cell (CAR-T) therapies have emerged as highly effective therapy for relapsed MCL, with the CAR-T treatment brexucabtagene autoleucel now approved for relapsed MCL. In this review the authors summarize evidence to date for currently approved MCL treatments for relapsed disease including sequencing of therapies, and discuss future directions including combination treatment strategies and new therapies under investigation.