High rate of durable remissions after treatment of newly diagnosed aggressive mantle-cell lymphoma with rituximab plus hyper-CVAD alternating with rituximab plus high-dose methotrexate and cytarabine

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.

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.

CD34+ Cell Mobilization, Autograft Cellular Composition and Outcome in Mantle Cell Lymphoma Patients

Backgound

Autologous stem cell transplantation (ASCT) is a standard treatment in transplant-eligible mantle cell lymphoma (MCL) patients after first-line chemoimmunotherapy.

Study Design and Methods

This prospective multicenter study evaluated the impact of CD34+ cell mobilization and graft cellular composition analyzed by flow cytometry on hematologic recovery and outcome in 42 MCL patients.

Results

During CD34+ cell mobilization, a higher blood CD34+ cell count (>30 × 106/L) was associated with improved overall survival (median not reached [NR] vs. 57 months, p = 0.04). The use of plerixafor did not impact outcome. Higher number of viable cryopreserved graft CD34+ cells (>3.0 × 106/kg) was associated with faster platelet (median 11 vs. 15 days, p = 0.03) and neutrophil (median 9 vs. 10 days, p = 0.02) recovery posttransplant. Very low graft CD3+CD8+ cell count (≤10 × 106/kg) correlated with worse progression-free survival (PFS) (HR 4.136, 95% CI 1.547-11.059, p = 0.005). On the other hand, higher absolute lymphocyte count >2.5 × 109/L at 30 days after ASCT (ALC-30) was linked with better PFS (median NR vs. 99 months, p = 0.045) and overall survival (median NR in either group, p = 0.05).

Conclusions

Better mobilization capacity and higher graft CD3+CD8+ cell count had a positive prognostic impact in this study, in addition to earlier lymphocyte recovery (ALC-30>2.5 × 106/L). These results need to be validated in another study with a larger patient cohort.

SOHO State of the Art Updates and Next Questions: Tailoring Upfront Therapy in Mantle Cell Lymphoma

In this article, we will review current strategies for the front-line management of mantle cell lymphoma, an uncommon and biologically and clinically heterogeneous subtype of non-Hodgkin lymphoma that remains incurable with current therapies. Patients invariably relapse with time, and as a result, treatment strategies involve persistent therapy over the course of months to years, including induction, consolidation, and maintenance. Topics discussed include the historical development of various chemoimmunotherapy backbones with continued modifications to maintain and improve efficacy while limiting off-target, off-tumor effects. Chemotherapy-free induction regimens were developed initially for elderly or less fit patients though are now being utilized for younger, transplant-eligible patients due to deeper, more prolonged remission durations with fewer toxicities. The historic paradigm of recommending autologous hematopoietic cell transplant for fit patients in complete or partial remission is now being challenged based in part on ongoing clinical trials in which minimal residual disease directed approaches influence the consolidation strategy for any particular individual. The addition of novel agents, namely first and second generation Bruton tyrosine kinase inhibitors as well as immunomodulatory drugs, BH3 mimetics, and type II glycoengineered anti-CD20 monoclonal antibodies have been tested in various combinations with or without immunochemotherapy. We will attempt to help the reader by systematically explaining and simplifying the various approaches for treating this complicated group of disorders.

Rituximab plus multiagent chemotherapy for newly diagnosed CD20-positive acute lymphoblastic leukemia: a prospective phase II study

BACKGROUND/AIMS

We performed a prospective study to determine the efficacy and safety of rituximab including chemotherapy in CD20-positive acute lymphoblastic leukemia (ALL).

METHODS

Patients with newly diagnosed ALL, aged ≥ 15 years, were eligible for the study if their leukemic blast cells in bone marrow expressed CD20 ≥ 20% at the time of diagnosis. Patients received multiagent chemotherapy with rituximab. After achieving complete remission (CR), patients received five cycles of consolidation with concomitant rituximab. Rituximab was administered monthly from day 90 of transplantation for patients who received allogeneic hematopoietic cell transplantation.

RESULTS

In patients with Philadelphia (Ph)-negative ALL, 39 of 41 achieved CR (95.1%), the 2- and 4-year relapse-free survival (RFS) rates were 50.4% and 35.7%, and the 2- and 4-year overall survival (OS) rates were 51.5% and 43.2%, respectively. In the group with Ph-positive ALL, all 32 patients achieved CR, the 2- and 4-year RFS rates were 60.7% and 52.1%, and the 2- and 4-year OS rates were 73.3% and 52.3%, respectively. In the Ph-negative ALL group, patients with higher CD20 positivity experienced more favorable RFS (p < 0.001) and OS (p = 0.06) than those with lower CD20 positivity. Patients who received ≥ 2 cycles of rituximab after transplantation had significantly improved RFS (hazard ratio [HR], 0.31; p = 0.049) and OS (HR, 0.29; p = 0.021) compared with those who received < 2 cycles.

CONCLUSION

The addition of rituximab to conventional chemotherapy for CD20-positive ALL is effective and tolerable (Clinicaltrials. gov NCT01429610).

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.

Blockade of CCR1 induces a phenotypic shift in macrophages and triggers a favorable antilymphoma activity

Tumor-associated macrophages (TAMs) within the tumor microenvironment (TME) play an important role in tumor growth and progression. TAMs have been involved in producing immunosuppressive TME via various factors; however, the underlying mechanisms remain unclear in B-cell lymphoma, including mantle cell lymphoma (MCL). We identified that chemokine receptor-1 (CCR1) is highly expressed on monocytes (Mo) and macrophages (MΦ), and CCR1 pharmacological inhibition or CCR1 siRNA abolished lymphoma-mediated Mo/MΦ migration in a chemotaxis assay. The deficiency of host CCR1 (CCR1 KO) was associated with decreased infiltration of peritoneal-MΦ compared with WT-CCR1. Functional studies indicated that the genetic depletion of CCR1 or treatment inhibited protumor MΦ (M2-like) phenotype by decreasing CD206 and IL-10 expression. Moreover, CCR1 depletion reprogrammed MΦ toward an MHCII+/TNFα+ immunogenic phenotype. Mechanistically, protumor MΦ driven-IL-10 provides a positive feedback loop to tumor-CCL3 by regulating the CCL3 promoter via STAT1 signaling. Therapeutic in vivo targeting of CCR1 with CCR1 antagonist BX-471 significantly reduced FC-muMCL1 mouse tumors in the syngeneic MCL model by the depletion of M2-TAMs and increased infiltration of cytotoxic CD8+ T cells. Our study established that CCR1 exerts a pivotal role in macrophage programming, thus shaping protumor TME and lymphoma progression. CCR1 inhibition through CCR1 antagonists may be a promising therapeutic strategy to reprogram macrophages in lymphoma-TME and achieve better clinical outcomes in patients.

Real-world treatment and outcome patterns of patients with mantle cell lymphoma in China: A large, multicenter retrospective analysis

BACKGROUND

Mantle cell lymphoma (MCL) is an uncommon heterogeneous subtype of B cell non-Hodgkin lymphoma, and clinical features in MCL appear regional characteristics. MCL treatment opinions are not uniform between countries or regions within Asia and China, and Asian patient-specific data for MCL treatment are fewer. The study aims to explore the clinical characteristics, treatment patterns and prognosis of MCL patients in China.

METHODS

A total of 805 patients diagnosed with MCL between April 1999 and December 2019 at 19 comprehensive hospitals in China were included in this retrospective analysis. Kaplan-Meier method coupled with the log-rank test was used for univariate analysis, and COX proportional hazards model was used for multivariate analysis (MVA). p < 0.05 was consided statistically significant. All outputs were produced using R version 4.1.0.

RESULTS

The median age of the cohort was 60.0 years with a male-to-female ratio of 3.36:1. Five-year progression-free survival (PFS) and overall survival (OS) rates were 30.9% and 65.0%, respectively. High-intermediate/high-risk group according to MIPI-c, without high-dose cytarabine, lack of Auto-SCT as consolidation and maintenance treatment and SD/PD in initial treatment remained statistically relevant to poor PFS on MVA, and ki67 ≥50%, B symptoms, high-intermediate/high risk group according to MIPI-c, without high-dose cytarabine, lack of maintenance treatment, SD/PD in initial treatment and relapse/refractory state were independently associated with poorer OS on MVA.

CONCLUSIONS

First-line high dose cytarabine exposure, auto-SCT as consolidation therapy obtained survival benefits in Chinese population. Our study further confirmed the value of maintenance treatment and explored the application of new drug treatment and bendamustine in R/R MCL patients.

Bendamustine/Rituximab Plus Cytarabine/Rituximab, With or Without Acalabrutinib, for the Initial Treatment of Transplant-Eligible Mantle Cell Lymphoma Patients: Pooled Data From Two Pilot Studies

INTRODUCTION

Mantle cell lymphoma (MCL) is a moderately aggressive lymphoma subtype, generally viewed as incurable. For younger, fit patients, the standard of care remains various high-dose cytarabine-based induction regimens followed by autologous hematopoietic cell transplant and 3 years of rituximab maintenance. Despite reasonably good outcomes, with median progression-free survival in the range of 7 to 9 years, most patients eventually relapse, indicating a need to improve the safety and tolerability of remission induction strategies.

METHODS

Given the impressive activity of bendamustine/rituximab (BR) in older patients with MCL, we developed an induction regimen modeled after the Nordic Regimen but substituted BR in place of R-CHOP. In a second pilot study, we incorporated the second-generation Bruton tyrosine kinase inhibitor (BTKi), acalabrutinib, into the regimen. The primary endpoint of both studies was stem cell mobilization success rate.

RESULTS

All patients successfully underwent stem cell harvest in both studies.

CONCLUSION

The experience from our single institution pilot study suggested that sequential rather than alternating BR and cytarabine/rituximab (CR) was easier to administer from the standpoint of toxicities and subsequent dose modifications. Safety and efficacy data from the 2 pilot studies, FitMCL 1.0 and 2.0, were similar. The pilot studies provided preliminary safety data supporting the development of the NCTN trial EA4181, assessing three different induction regimens with or without acalabrutinib.

Long-term outcome in patients with mantle cell lymphoma following high-dose therapy and autologous stem cell transplantation

BACKGROUND

Long-term clinical and molecular remissions in patients with mantle cell lymphoma (MCL) after autologous stem cell transplantation (ASCT) have been evaluated in only a few studies.

DESIGN AND METHODS

Sixty-five patients with MCL received ASCT (54 first-line ASCT, 10 second-line ASCT, and 1 third-line ASCT). In the case of long-term remission (≥5 years; n = 27), peripheral blood was tested for minimal residual disease (MRD) by t(11;14)- and IGH-PCR at the last follow-up.

RESULTS

Ten-year overall survival (OS), progression-free survival (PFS), and freedom from progression (FFP) after first-line ASCT were 64%, 52%, and 59% versus after second-line ASCT 50%, 20%, and 20%, respectively. Five-year OS, PFS, and FFP for the first-line cohort were 79%, 63%, and 69%, respectively. Five-year OS, PFS, and FFP after second-line ASCT were 60%, 30%, and 30%, respectively. Treatment-related mortality (3 months after ASCT) was 1.5%. So far 26 patients developed sustained long-term clinical and molecular complete remissions of up to 19 years following ASCT in first treatment line.

CONCLUSION

Sustained long-term clinical and molecular remissions are achievable following ASCT.

How I manage mantle cell lymphoma: indolent versus aggressive disease

Mantle cell lymphoma (MCL) is a mature B-cell lymphoma with a variable clinical course and historically poor prognosis. Management is challenging in part due to the heterogeneity of the disease course, with indolent and aggressive subtypes now well recognised. Indolent MCL is often characterised by a leukaemic presentation, SOX11 negativity and low proliferation index (Ki-67). Aggressive MCL is characterised by rapid onset widespread lymphadenopathy, extra-nodal involvement, blastoid or pleomorphic histology and high Ki-67. Tumour protein p53 (TP53) aberrations in aggressive MCL are recognised with clear negative impact on survival. Until recently, trials have not addressed these specific subtypes separately. With the increasing availability of targeted novel agents and cellular therapies, the treatment landscape is constantly evolving. In this review, we describe the clinical presentation, biological factors, and specific management considerations of both indolent and aggressive MCL and discuss current and potential future evidence which may help move to a more personalised approach.

Personalized approaches for treatment-naïve mantle cell lymphoma

INTRODUCTION

Mantle cell lymphoma (MCL) can have diverse disease presentations, which vary in aggressiveness and prognosis, and can occur in patients with varying ability to tolerate therapy. Additionally, the options for treatment of MCL have expanded rapidly in the last decade, translating to improved outcome for patients.

AREAS COVERED

We review the initial evaluation of patients with MCL, identifying disease- and patient-specific prognostic factors, along with personalized therapies for patients with MCL. Specific scenarios include indolent and limited-stage MCL, advanced-stage disease in transplant-eligible and ineligible patients, and high-risk TP53 mutant disease. Ongoing trials and future directions in MCL treatment are also highlighted.

EXPERT OPINION

Given the wide array of disease and patient presentations with MCL, a personalized therapeutic approach is needed to optimize outcomes. The best therapeutic strategy should incorporate disease prognostic factors, patient status and comorbidities, goals of care, and response to treatment.

Impact of Pre-transplant Induction Therapy on Outcomes of Patients Who Undergo Autologous Stem Cell Transplantation for Mantle Cell Lymphoma in First Complete Remission

Mantle cell lymphoma is a rare subtype of non-Hodgkin's lymphoma with poor prognosis and continue to be challenging to treat. The choice of first line induction regimen remains a topic of debate due paucity of clinical trials. We retrospectively evaluated 66 patients diagnosed with mantle cell lymphoma who achieved first complete response after induction chemotherapy followed by autologous stem cell transplant. Treatment groups were divided into low-intensity versus high-intensity regimens. Our data showed the intensity of induction regimen does not impact posttransplant outcomes of mantle cell lymphoma who underwent autologous stem cell transplant in first complete response.

First-Line Autologous Stem Cell Transplantation for Mantle Cell Lymphoma: A Systematic Analysis and Treatment Recommendation

Background

In the era of immunotherapy, autologous stem cell transplantation (ASCT) in first-line therapy in patients with mantle cell lymphoma (MCL) has been a controversial topic. This report aimed to explore the association between ASCT and MCL survival through a systematic review with meta-analysis.

Methods

We performed a systematic search of original articles published from inception to September 2021 using PubMed, MEDLINE, Embase, and Cochrane Library databases.

Results

We included studies that compared ASCT with non-ASCT consolidation in newly diagnosed transplant-eligible MCL. The endpoints were progression-free survival (PFS) and overall survival (OS). There were seven eligible studies (one randomized clinical trial, one prospective cohort study, and five observational studies) published between 2012 and 2021, in which the total number of participants was 3,271. In the non-intensive induction subgroup, patients with ASCT experienced a significant PFS but no OS benefit compared with those without ASCT. In the intensive induction subgroup, the PFS benefit from ASCT still existed but largely attenuated; no OS benefit was observed though only one study was suitable for evaluation. When compared to the rituximab maintenance arm, ASCT had a worse PFS and OS.

Conclusions

In the rituximab plus HiDAC era, the benefit of ASCT as a component of first-line treatment has been weakened. First-line maintenance strategy instead of ASCT seems worth exploring .

Monoclonal antibodies: new chance in the management of B-cell acute lymphoblastic leukemia

OBJECTIVES

This review aims to see the progress of several clinically-used monoclonal antibodies in treating ALL patients and how they improved patients' outcomes.

METHODS

We searched Web of Science, Elsevier and PubMed for relevant published studies, and summarized eligible evidence on the management of newly-diagnosed and relapsed or refractory ALL with monoclonal antibodies. Ongoing trials were identified from ClinicalTrials.gov.

RESULTS

Rituximab, an anti-CD20 monoclonal antibody, prolonged patients' complete remission duration and overall survival when combined with hyper-CVAD regimen. Another anti-CD20 monoclonal antibody, Ofatumumab, was reported to have similar benefits. Blinatumomab allows endogenous CD3-positive cytotoxic T cells to target and eliminate CD19-positive blasts. FDA has approved its efficacy in patients with R/R B-ALL and eliminating minimal residual disease (MRD). It serves as a bridge to eradicate MRD before transplantation, and may also be a new choice for patients unable to undergo transplantation. An anti-CD22 monoclonal antibody named Inotuzumab Ozogamicin showed great improvement in patients' outcome, but its toxicity to liver is also worthy of our attention.

CONCLUSION

Monoclonal antibodies are proven to be a promising immunotherapeutic strategy to improve ALL patients' outcome in the long term. There's still a need for individualized treatment with effective and well-tolerated medicines.Trial registration: ClinicalTrials.gov identifier: NCT01363128.Trial registration: ClinicalTrials.gov identifier: NCT01466179.Trial registration: ClinicalTrials.gov identifier: NCT02013167.Trial registration: ClinicalTrials.gov identifier: NCT02000427.Trial registration: ClinicalTrials.gov identifier: NCT01564784.Trial registration: ClinicalTrials.gov identifier: NCT03677596.Trial registration: ClinicalTrials.gov identifier: NCT01363297.Trial registration: ClinicalTrials.gov identifier: NCT02981628.Trial registration: ClinicalTrials.gov identifier: NCT03094611.Trial registration: ClinicalTrials.gov identifier: NCT01371630.Trial registration: ClinicalTrials.gov identifier: NCT04224571.Trial registration: ClinicalTrials.gov identifier: NCT02458014.Trial registration: ClinicalTrials.gov identifier: NCT04546399.Trial registration: ClinicalTrials.gov identifier: NCT02879695.Trial registration: ClinicalTrials.gov identifier: NCT03913559.Trial registration: ClinicalTrials.gov identifier: NCT03441061.Trial registration: ClinicalTrials.gov identifier: NCT03739814.Trial registration: ClinicalTrials.gov identifier: NCT02877303.Trial registration: ClinicalTrials.gov identifier: NCT03698552.Trial registration: ClinicalTrials.gov identifier: NCT04601584.Trial registration: ClinicalTrials.gov identifier: NCT04684147.Trial registration: ClinicalTrials.gov identifier: NCT04681105.

New Directions for Mantle Cell Lymphoma in 2022

Mantle cell lymphoma is a rare B-cell non-Hodgkin lymphoma that is clinically and biologically heterogeneous. Risk stratification at the time of diagnosis is critical. One of the most powerful prognostic indices is the Mantle Cell Lymphoma International Prognostic Index-Combined, which integrates an estimate of proliferation (Ki67 index) with the standard Mantle Cell Lymphoma International Prognostic Index clinical factors. In addition, the presence of TP53 mutation is associated with suboptimal response to intensive chemoimmunotherapy and particularly dismal survival outcomes. Given their excellent activity in the relapsed/refractory setting, increasingly, biologically targeted therapeutics-such as covalent Bruton tyrosine kinase inhibitors, lenalidomide, and venetoclax-are being incorporated into "chemotherapy-free" regimens and in combination with established chemoimmunotherapy backbones for treatment-naïve mantle cell lymphoma. In addition, risk-adapted treatment programs are increasingly being studied. These programs tailor treatment according to baseline prognostic factors (e.g., presence of TP53 mutation) and may incorporate biomarkers of response such as minimal residual disease assessment. Although still investigational, these studies present an opportunity to move beyond the biology-agnostic, historical fitness-based treatment selection paradigm and toward a more personalized, tailored treatment approach in mantle cell lymphoma. After Bruton tyrosine kinase inhibitor failure, many promising standard or investigational therapies exist, including CAR T-cell therapy (including brexucabtagene autoleucel and lisocabtagene maraleucel), bispecific antibody therapy targeting CD20-CD3, zilovertamab vedotin (an antibody-drug conjugate that targets ROR1), and the noncovalent Bruton tyrosine kinase inhibitor pirtobrutinib. These new therapies show promising efficacy, even among high-risk patients, and will likely translate to improvements in survival outcomes for patients with progressive mantle cell lymphoma following treatment with a Bruton tyrosine kinase inhibitor.

Immunotherapy in indolent Non-Hodgkin's Lymphoma

Treatment of non-Hodgkin lymphoma (NHL) in general has improved over the years with the emergence of the monoclonal antibodies (MAB) therapy. NHL is divided into B cell NHL and T cell NHL. Treatment of NHL was based on the subtype of NHL and its staging. NHL is divided into aggressive and indolent NHL (iNHL). Subtypes of iNHL include: Follicular lymphoma (FL), Marginal zone lymphoma (MZL), Chronic lymphocytic leukemia/small-cell lymphocytic lymphoma (CLL/SLL), Gastric mucosa-associated lymphoid tissue (MALT) lymphoma, Lymphoplasmacytic lymphoma, Waldenström macroglobulinemia, Nodal marginal zone lymphoma (NMZL), Splenic marginal zone lymphoma (SMZL). Chemotherapy was the main stay treatment of iNHL until the emergence of Rituximab, anti-CD20 MAB targeting CD-20 surface cell antigens that are present on B-cells lymphoma and not on precursor cells, mainly efficacious in B cell iNHL, It became the mainstay treatment in follicular lymphoma (FL) as a single agent modality or in combination with chemotherapy. The anti-CD20 Rituximab played an important role in the development of the treatment of iNHL to become FDA approved in 1997. It was also proven effective in multiple other types of lymphoma. MAB through targeting the cell surface antigen leads to a direct or immune mediated cytotoxicity. This carries few side effects, including allergic reactions. Other than that, a resistance mechanism to rituximab emerged by inducing a failure in the apoptosis mechanism. Alternative mechanisms of resistance included the presence of soluble antigens that could act by binding to the antibody present before the drug itself can bind the lymphoma cell. Thus, the interest in immunotherapy grew further to explore the possibility of conjugating an immune mediated drug to a radio-sensitizing agent in order to enhance the selectivity of the drug. Here came the development of 90Y-ibritumomab tiuxetan and 131I-tositumomab. After it, humanized anti-CD20 emerged ofatumumab, IMMU106 (veltuzumab) in 2005, and ocrelizumab which are considered as second generation anti-CD20 and 3^rd generation anti-CD20 include AME-133v (ocaratuzumab), PRO131921 and GA101 (obinutuzumab). Also multiple other agents emerged targeting different surface cell antigens like CD52 (alemtuzumab), CD22 (unconjugated epratuzumab and calicheamicin conjugated CMC-544 [inotuzumab ozogamicin]), CD80 (galiximab), CD2 (MEDI-507 [siplizumab]), CD30 (SGN-30 and MDX-060 [iratumumab], Brentuximab vedotin), CD40 (SGN-40), and CD79b (Polatuzumab). Other agents include MAB targeting T-Cells like mogamulizumab, Denileukin Diftitox and BiTEs or bispecific T cell engagers like Mosunetuzumab, Glofitamab, and Epcoritamab. Moreover, further studies came up to evaluate the role of immunotherapy in combination chemotherapy as a pathway to evade the resistance mechanisms. Side effects of the treatment were mainly infusion related adverse reactions, myelosuppression in conjugated forms leading to immunosuppression and subsequently to infectious complications. Another important aspect in immunotherapy is the half-lives of the medication which is an important factor that can influence the evaluation of the response. The MAB treatment showed important benefit in the treatment of iNHL and it continuously shows how rapidly it can develop to provide optimum care and benefit to patients with iNHL.

Mantle cell lymphoma in 2022-A comprehensive update on molecular pathogenesis, risk stratification, clinical approach, and current and novel treatments

The field of mantle cell lymphoma (MCL) has witnessed remarkable progress due to relentless advances in molecular pathogenesis, prognostication, and newer treatments. MCL consists of a spectrum of clinical subtypes. Rarely, atypical cyclin D1-negative MCL and in situ MCL neoplasia are identified. Prognostication of MCL is further refined by identifying somatic mutations (such as TP53, NSD2, KMT2D), methylation status, chromatin organization pattern, SOX-11 expression, minimal residual disease (MRD), and genomic clusters. Lymphoid tissue microenvironment studies demonstrated the role of B-cell receptor signaling, nuclear factor kappa B (NF-kB), colony-stimulating factor (CSF)-1, the CD70-SOX-11 axis. Molecular mechanism of resistance, mutation dynamics, and pathogenic pathways (B-cell receptor (BCR), oxidative phosphorylation, and MYC) were identified in mediating resistance to various treatments (bruton tyrosine kinase (BTK) inhibitors [ibrutinib, acalabrutinib]. Treatment options range from conventional chemoimmunotherapy and stem cell transplantation (SCT) to targeted therapies against BTK (covalent and noncovalent), Bcl2, ROR1, cellular therapy such as anti-CD19 chimeric antigen receptor therapy (CAR-T), and most recently bispecific antibodies against CD19 and CD20. MCL patients frequently relapse. Complex pathogenesis and the management of patients with progression after treatment with BTK/Bcl2 inhibitors and CAR-T (triple-resistant MCL) remain a challenge. Next-generation clinical trials incorporating newer agents and concurrent translational and molecular investigations are ongoing.

Stem cell transplant for mantle cell lymphoma in Taiwan

Mantle cell lymphoma (MCL) is a B-cell lymphoma featuring an aggressive course and a progressive relapsing pattern. International guidelines recommend early consolidative autologous stem cell transplant (auto-SCT) for eligible patients while reserving allogeneic SCT (allo-SCT) as therapy for refractory cases. Since data describing the implementation of transplants in the Asian population with MCL are limited, we aimed to analyze post-SCT outcomes of 99 MCL patients from the Taiwan Bone Marrow Transplant Registry database. The median age was 56 years, and 11% of the patients had blastoid variant MCL. Ninety-four patients received auto-SCT, while 13 patients received allo-SCT, eight of which received allo-SCT after failing auto-SCT. Before auto-SCT, 52% of the patients were in their first complete remission (CR1). Overall, 37 patients (39%) relapsed after auto-SCT. The median post-auto-SCT progression-free survival and overall survival (OS) were 43.6 months and not reached, respectively. Blastoid variant MCL, transplant not received in CR1, and disease progression within 12 months post-auto-SCT independently predicted inferior OS in multivariable analysis. The median post-allo-SCT OS was 74 months. Two patients (15%) died of MCL recurrence post-allo-SCT. Three patients with refractory diseases were salvaged with ibrutinib or venetoclax to allo-SCT. Treatment strategies incorporating novel agents warrant further optimization.

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.

Ofatumumab plus HyperCVAD/HD-MA induction leads to high rates of minimal residual disease negativity in patients with newly diagnosed mantle cell lymphoma, results of a phase 2 study

BACKGROUND

Ofatumumab is a humanized type 1 anti-CD20 monoclonal antibody. Preclinical studies show improved complement-mediated cytotoxicity (CMC) compared to rituximab in mantle cell lymphoma (MCL). This study evaluates the safety and efficacy of combining ofatumumab with HyperCVAD/MA (O-HyperCVAD) in newly diagnosed MCL.

METHODS

In this single-arm phase 2 study, 37 patients were treated with the combination of O-HyperCVAD for 4 or 6 cycles, followed by high dose chemotherapy and autologous stem cell transplant. Primary objectives were overall response rate (ORR) and complete response (CR) rate at the end of therapy. Secondary objectives included minimal residual disease (MRD) negativity, progression-free survival (PFS), and overall survival (OS).

RESULTS

Median age was 60 years; ORR was 86% and 73% achieved a CR by modified Cheson criteria. The MRD negativity rate was 78% after 2 cycles of therapy, increasing to 96% at the end of induction; median PFS and OS were 45.5 months and 56 months, respectively. Achieving a post-induction CR by both imaging and flow cytometry was associated with improved PFS and OS. Early MRD negativity (post-2 cycles) was also associated with an improved PFS but not OS. There were 3 deaths while on therapy, and grades 3 and 4 adverse events (AEs) were observed in 22% and 68% of the patients.

CONCLUSION

The addition of ofatumumab to HyperCVAD/HD-MA led to high rates of MRD negativity by flow cytometry in patients with newly diagnosed MCL. Achieving a CR post-induction by both imaging and flow cytometry is associated with improved overall survival.

Circulating Tumor DNA Predicts Therapeutic Outcome in Mantle Cell Lymphoma

Early changes in ctDNA dynamics are prognostic in untreated MCL.

Bortezomib maintenance after bortezomib-based induction therapy does not improve outcome in untreated MCL.

Mantle cell lymphoma (MCL) is biologically and clinically heterogeneous and would benefit from prognostic biomarkers to guide management. Circulating tumor DNA (ctDNA) is a novel prognostic biomarker in diffuse large B-cell lymphoma that may have applicability in MCL. We analyzed ctDNA dynamics in previously untreated patients with MCL who received induction therapy with bortezomib and DA-EPOCH-R for 6 cycles followed by random assignment to observation or bortezomib maintenance in responding patients in a prospective phase 2 study. Most patients also underwent initial treatment window of bortezomib alone prior to induction. Serum was collected pretreatment, after the window, after cycles 1 and 2, at the end of induction, and at each follow-up visit along with restaging computed tomography scans. Next-generation sequencing was used to identify and quantify ctDNA encoding the immunoglobulin receptor sequences in serum as markers of minimal residual disease. Fifty-three patients were enrolled, with a median follow-up of 12.7 years. Patients without detectable ctDNA after 2 cycles of induction had longer progression-free survival (PFS) and overall survival (OS) compared with those with detectable ctDNA (median PFS, 2.7 vs 1.8 years; overall P = .005; median OS, 13.8 vs 7.4 years; overall P = .03). Notably, in vivo assessment of ctDNA dynamics during the bortezomib window was not prognostic, and there was no difference in PFS or OS with bortezomib maintenance. ctDNA monitoring after induction showed that molecular relapse preceded clinical relapse in some cases. In conclusion, interim ctDNA negativity strongly correlates with improved survival and supports the investigation of response-adapted strategies. This trial was registered at www.clinicaltrials.gov as #NCT00114738.

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.

Cellular Therapy Updates in B-Cell Lymphoma: The State of the CAR-T

Simple Summary

B-cell lymphomas are the most commonly occurring blood cancer and the second leading cause of cancer-related death among blood cancers. Chemotherapy and stem cell transplantation have long served as the standard therapies for relapsed or refractory aggressive B-cell lymphomas with very poor survival, historically. Recently, the development of multiple chimeric antigen receptor T-cell (CAR-T) products has translated into dramatically improved outcomes and survival for patients with relapsed or refractory B-cell lymphoma. Meanwhile, basic, translational and clinical development within the field has progressed rapidly. The aim of this review is to summarize the current state of the art of CAR-T therapies for B-cell lymphomas within this rapidly evolving field, focusing on current United States Food and Drug Administration (US FDA)-approved products and a selection of promising areas of future clinical development.

Abstract

Non-Hodgkin Lymphoma accounts for >460,000 cases and >240,000 deaths globally and >77,000 cases and >20,000 deaths in the U.S. annually, with ~85% of cases being B-cell malignancies. Until recently, patients with relapsed/refractory B-cell lymphoma following standard chemotherapy in combination with anti-CD20 monoclonal antibodies and autologous stem cell transplantation experienced a median overall survival (OS) of <6 months. However, with the approval of four different CD-19 CAR-T therapies between 2017 and 2021, approximately 60–80% of patients receiving CAR-T therapy now achieve an objective response with >3 years median OS. Here, we review the current state of the art of CD19 CAR-T therapies for B-cell lymphomas, focusing on current updates in US FDA-approved products, along with their associated efficacy and toxicities. Lastly, we highlight a selection of promising clinical developments in the field, including various novel strategies to increase CAR-T therapy efficacy while mitigating toxicity.

Efficacy of chemotherapy protocols for hematological malignancies: H-CVAD versus GELA/BURKIMAB/PETHEMA LAL

The hyper-CVAD/methotrexate-cytarabine (H-CVAD/ MTX-AraC) chemotherapy protocol has been one of the standard treatments for hematological malignancies, such as mantle cell lymphoma (MCL), Burkitt lymphoma (BL), and B-cell and T-cell acute lymphoblastic leukemia. Because results of this therapy are poor, it has been progressively replaced with new specific regimens with better efficacy profiles (GELA protocol for MCL, BURKIMAB for BL, and PETHEMA for B-cell and T-cell acute lymphoblastic leukemia [ALL]). The objective of this study was to analyze the response rates and survival of these therapeutic regimens. This retrospective and descriptive observational study of 81 patients compared 42 patients treated with hyper-CVAD/methotrexate-cytarabine (group A) with 39 patients treated with GELA/BURKIMAB/PETHEMA (group B). More patients in group B than in group A completed the treatment (89.7% vs. 47.6%, p < 0.001). In group A, 14.3% did not complete treatment because of death compared with 7.7% in group B, and 29% in group A had cycle delays versus 6.7% in group B (p < 0.001). In group A, 78.6% of group A achieved a complete response (CR) compared with 94.9% of group B (p = 0.050). Disease-free survival (DFS) and overall survival (OS) were significantly higher in group B (p < 0.001 in both cases). Data for current therapeutic protocols have indicated superior efficacy, with higher complete response rates, as well as better disease-free survival and overall survival results. This article provides the best results in terms of the efficacy of treatment of four hematological malignancies (MCL, BL, B-cell ALL, and T-cell ALL) with the most current specific therapeutic regimens (GELA for MCL, BURKIMAB for BL, and PETHEMA for B-cell ALL and T-cell ALL) with respect to a classic general protocol (H-CVAD/MTX-AraC for all four). These results may represent a great advance in the treatment of these blood cancers, achieving an important long-term benefit for these hematological patients.

Treatment patterns among patients with mantle cell lymphoma and comparison of healthcare resource utilization and costs among relapsed/refractory patients treated with ibrutinib or chemoimmunotherapy: A real-world retrospective study

PURPOSE

This study assessed treatment patterns in patients with mantle cell lymphoma (MCL) and compared health care resource utilization (HRU) and costs of ibrutinib with or without rituximab (I ± R) versus chemoimmunotherapy (CIT) in patients with relapsed/refractory MCL.

METHODS

For this retrospective cohort study, adults with MCL observed between May 13, 2013, and June 30, 2019, were identified using Optum's de-identified Clinformatics Data Mart Database. Treatment patterns were described among patients who received ≥1 line of therapy (LOT). HRU and costs (payer's perspective) were compared between patients treated with I ± R and CIT in the second or later line (2L+) of therapy. To account for differences in baseline characteristics between the 2 cohorts, inverse probability of treatment weighting was used. Monthly HRU and costs starting from I ± R or CIT treatment initiation (index date) were compared during the first Oncology Care Model (OCM) episode (ie, first 6 months) postindex and during the observed duration of I ± R or CIT LOT (index LOT) using rate ratios (RRs) and mean monthly cost differences (MMCDs), respectively.

FINDINGS

Among 1346 patients with ≥1 LOT (median follow-up, 15.3 months), 870 (64.6%) were treated with CIT in the first line. Only 348 (25.9%) had a 2L of therapy, of whom 110 (31.6%) were treated with CIT and 98 (28.2%) with an ibrutinib-based therapy. A total of 300 patients were included for the comparison of HRU and costs between 2L+ I ± R and 2L+ CIT. The weighted cohorts (after inverse probability of treatment weighting) included 149 patients treated with I ± R (mean age, 71.6 years; 73.7% men) and 151 treated with CIT (mean age, 71.5 years; 76.2% men). During the first OCM episode and during the index LOT, the I ± R cohort had significantly fewer monthly days with outpatient services compared to the CIT cohort (OCM, RR = 0.63 [P < 0.001]; index LOT, RR = 0.73 [P = 0.004]). Compared to the CIT cohort, the I ± R cohort incurred significantly higher monthly pharmacy costs (MMCDs: OCM, 9938 US dollars [USD] [P < 0.001]; index LOT, 8920 USD [P < 0.001]) that were fully offset by lower monthly medical costs (MMCDs: OCM, -19,373 USD [P < 0.001]; index LOT, -13,548 USD [P < 0.001]), resulting in monthly total health care cost savings (MMCDs, OCM, -9435 USD [P < 0.001]; index LOT , -4628 USD [P = 0.01]).

IMPLICATIONS

Over a median follow-up of 15.3 months, most patients with MCL were treated with CIT in the first line, and only one fourth had a 2L therapy. Patients with relapsed/refractory MCL treated with I ± R had significantly fewer days with outpatient services and lower monthly total health care costs versus those treated with CIT during the first OCM episode and the index LOT.

R-MACLO-IVAM regimen followed by maintenance therapy induces durable remissions in untreated mantle cell lymphoma - Long term follow up results

We present long-term combined results of two clinical trials implementing R-MACLO-IVAM induction followed by thalidomide or rituximab maintenance in 44 patients with untreated mantle cell lymphoma (MCL). The first 22 patients (UM-MCL1 ClinicalTrials.gov identifier NCT00450801) received maintenance with thalidomide (200 mg daily until relapse/intolerable toxicity) and a subsequent cohort of 22 patients (UM-MCL2 ClinicalTrials.gov identifier NCT00878254) received rituximab (375 mg/m² IV weekly × 4, repeated every 6 months for 3 years). Considering all 44 patients, 41 (93.2%) achieved complete response (CR), two (4.5%) partial response (PR), and one (2.3%) was not evaluated for response. With a median follow up of 7.2 years (range < 1 month to 16 years), the 5-year progression-free survival (PFS) was 55.6% (95% CI: 38.9%-69.4%) and median PFS 7.9 years (95% CI: 3.7-11 years). The 5-year OS was 83.3% (95% CI: 68.1%-91.7%) and median OS was not reached. Patients with blastic variant (n = 6) had a 5-year PFS and OS of 20.8% and 60%, respectively. Myelosuppression was the most common adverse event during immunochemotherapy. Long-term treatment-related mortality was 6.8%. Note, R-MACLO-IVAM followed by maintenance therapy is an effective regimen to induce long-term remission in MCL without need for consolidation with ASCT.

Treatment patterns and outcomes of older patients with mantle cell lymphoma in an Asian population

Background

Significant progress has been made in the treatment outcomes of mantle cell lymphoma (MCL) since the introduction of cytarabine and rituximab in modern regimens. However, older patients may not readily tolerate these agents nor derive benefit. We investigated the impact of age on treatment patterns and clinical outcomes of MCL patients in an Asian population.

Methods

A retrospective study was conducted on patients (n = 66) diagnosed with MCL at the National Cancer Centre Singapore between 1998 and 2018. The median follow-up duration was 40 months. Survival analyses were performed using the Kaplan-Meier method and multivariate Cox proportional models.

Results

The median age of the cohort was 59 years (range, 26–84), with a male predominance (73%). The majority (86%) had advanced stage 3–4 disease at diagnosis. Compared with younger patients, older patients aged ≥60 years (n = 32; 48.5%) presented more frequently with B-symptoms (75% vs 38%, p = 0.0028), anaemia (75% vs 35%, p = 0.0013), and carried higher prognostic risk scores (sMIPI high risk 84% vs 56%, p = 0.016). Non-cytarabine-based induction chemotherapy was more commonly administered in older patients (76% vs 32%, p = 0.0012). The 5-year overall survival (OS) and progression-free survival (PFS) was 68 and 25% respectively. In a multivariable model, older age (HR 3.42, 95%CI 1.48–7.92, p = 0.004) and anemia (HR 2.56, 95%CI 1.10–5.96, p = 0.029) were independently associated with poorer OS while older age (HR 2.24, 95%CI 1.21–4.14, p = 0.010) and hypoalbuminemia (HR 2.20, 95%CI 1.17–4.13, p = 0.014) were independently associated with poorer PFS. In an exploratory analysis, maintenance rituximab following induction chemotherapy improved PFS in younger patients, with median PFS of 131 months and 45 months with or without maintenance therapy respectively (HR 0.39, 95%CI 0.16–0.93, p = 0.035). In contrast, no survival benefit was observed in older patients.

Conclusions

We demonstrated in our analysis that older patients with MCL may harbor adverse clinical features and may not derive benefit from maintenance rituximab, highlighting the need for further research in this area of need.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08326-1.

Immune recovery in patients with mantle cell lymphoma receiving long-term ibrutinib and venetoclax combination therapy

Combination venetoclax plus ibrutinib for the treatment of mantle cell lymphoma (MCL) has demonstrated efficacy in the relapsed or refractory setting; however, the long-term impact on patient immunology is unknown. In this study, changes in immune subsets of MCL patients treated with combination venetoclax and ibrutinib were assessed over a 4-year period. Multiparameter flow cytometry of peripheral blood mononuclear cells showed that ≥12 months of treatment resulted in alterations in the proportions of multiple immune subsets, most notably CD4+ and CD8+ effector and central memory T cells and natural killer cells, and normalization of T-cell cytokine production in response to T-cell receptor stimulation. Gene expression analysis identified upregulation of multiple myeloid genes (including S100 and cathepsin family members) and inflammatory pathways over 12 months. Four patients with deep responses stopped study drugs, resulting in restoration of normal immune subsets for all study parameters except myeloid gene/pathway expression, suggesting long-term combination venetoclax and ibrutinib irreversibly affects this population. Our findings demonstrate that long-term combination therapy is associated with immune recovery in MCL, which may allow responses to subsequent immunotherapies and suggests that this targeted therapy results in beneficial impacts on immunological recovery. This trial was registered at www.clinicaltrials.gov as #NCT02471391.

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.

Autologous tumor cell vaccine induces antitumor T cell immune responses in patients with mantle cell lymphoma: A phase I/II trial

Here, we report on the results of a phase I/II trial (NCT00490529) for patients with mantle cell lymphoma who, having achieved remission after immunochemotherapy, were vaccinated with irradiated, CpG-activated tumor cells. Subsequently, vaccine-primed lymphocytes were collected and reinfused after a standard autologous stem cell transplantation (ASCT). The primary endpoint was detection of minimal residual disease (MRD) within 1 yr after ASCT at the previously validated threshold of ≥1 malignant cell per 10,000 leukocyte equivalents. Of 45 evaluable patients, 40 (89%) were found to be MRD negative, and the MRD-positive patients experienced early subsequent relapse. The vaccination induced antitumor CD8 T cell immune responses in 40% of patients, and these were associated with favorable clinical outcomes. Patients with high tumor PD-L1 expression after in vitro exposure to CpG had inferior outcomes. Vaccination with CpG-stimulated autologous tumor cells followed by the adoptive transfer of vaccine-primed lymphocytes after ASCT is feasible and safe.

Invited Review: Will Consolidation with ASCT Be a Thing of the Past for MCL and PTCL?

PURPOSE OF REVIEW

The treatment landscape of mantle cell (MCL) and peripheral T-cell lymphomas (PTCL) is rapidly changing; however, despite improvement in patients' survival, they still remain a largely incurable diseases. Treatment choice is dependent on patient factors, prior therapy, remission duration, and candidacy for stem cell transplantation (SCT). There are subsets of high-risk patients who do not benefit substantially from autologous SCT (ASCT) and for whom alternative targeted approaches are being examined. Here, we critically analyze the actual role of ASCT in PTCL and MCL.

RECENT FINDINGS

Research in areas of maintenance therapy and minimal residual disease is ongoing to identify MCL patients who may not require ASCT for durable response. Moreover, there are subsets of high-risk MCL patients who do not benefit substantially from ASCT and for whom alternative, targeted approaches are being examined. Much less clear evidence exists regarding the impact of consolidative ASCT in PTCL, mainly for the heterogeneity of these lymphomas: it is still controversial whether patients who achieved a complete response significantly take advantage of this procedure over active surveillance only. Several clinical and biologic markers are available to predict prognosis; however, despite improvements in outcomes, standard therapeutic approaches have not been able to overcome high-risk disease features for PTCL and MCL. Thus, the need of ASCT for these diseases is still matter of debate among hematologists.

High-Risk Mantle Cell Lymphoma in the Era of Novel Agents

PURPOSE OF REVIEW

Mantle cell lymphoma (MCL) is a heterogenous disease with a variety of morphologic and genetic features, some of which are associated with high risk disease. Here we critically analyze the current state of the understanding of MCL's biology and its implications in therapy, with a focus on chemotherapy-free and targeted therapy regimens.

RECENT FINDINGS

Mantle cell lymphoma (MCL) is a rare subtype of non-Hodgkin's lymphoma, defined by a hallmark chromosomal translocation t(11;14) which leads to constitutive expression of cyclin D1. Recent discoveries in the biology of MCL have identified a number of factors, including TP53 mutations and complex karyotype, that lead to unresponsiveness to traditional chemoimmunotherapy and poor outcomes. Bruton tyrosine kinase inhibitors, BH3-mimetics and other novel agents thwart survival of the neoplastic B-cells in a manner independent of high-risk mutations and have shown promising activity in relapsed/refractory MCL. These therapies are being investigated in the frontline setting, while optimal responses to chemotherapy-free regimens, particularly in high-risk disease, might require combination approaches. High-risk MCL does not respond well to chemoimmunotherapy. Targeted agents are highly active in the relapsed refractory setting and show promise in high-risk disease. Novel approaches may soon replace the current standard of care in both relapsed and frontline settings.

Clinical efficacy and safety of first-line treatments in patients with mantle cell lymphoma: A systematic literature review

Mantle cell lymphoma (MCL) is a rare form of non-Hodgkin's lymphoma (NHL) with a median overall survival (OS) of approximately 3-5 years. Systematic literature reviews (SLRs) identified efficacy and safety data for first-line therapies, reported in randomised controlled trials (RCTs) and non-randomised interventional studies (NRISs). Nine and 20 independent studies were included in the RCT and NRISs SLRs, respectively. Differences in the regimens and patient outcomes varied according to patient age and suitability for autologous stem cell transplantation (ASCT). In elderly patients ineligible for transplant, OS ranged from 40 months to 69.6 months. In young transplant-eligible patients, OS ranged from 53 months to 152.4 months. Despite the paucity of directly comparable evidence on the efficacy and safety of MCL therapies, these SLRs highlight that MCL remains a difficult NHL subtype to treat, with short survival highlighting the unmet need for newer treatments that improve patient outcomes.

Detailed Long-Term Follow-Up of Patients Who Relapsed After the Nordic Mantle Cell Lymphoma Trials: MCL2 and MCL3

Mantle cell lymphoma (MCL) is an incurable disease with a highly variable clinical course. The prognosis after relapse is generally poor, and no standard of care exists. We investigated the postrelapse outcomes of 149 patients who were initially treated in the Nordic Lymphoma Group trials, MCL2 or MCL3, both representing intensive cytarabine-containing frontline regimens including autologous stem cell transplant. Patients with progression of disease before 24 months (POD24, n = 51, 34%) displayed a median overall survival of 6.6 months compared with 46 months for patients with later POD (n = 98, 66%; P < 0.001). MCL international prognostic index, cell proliferation marker, blastoid morphology, and TP53 mutations showed independent prognostic value irrespective of POD24, and in a combined, exploratory risk score, patients with 0, 1, 2-3, or 4-5 high-risk markers, respectively, displayed a 5-year overall survival of 62%, 39%, 31%, and 0%. By a comparison of median progression-free survival of the different salvage therapies in the relapse setting, bendamustine-rituximab was superior to all other combination chemotherapy regimens; however, it was also associated with longer responses to last line of therapy. Collectively, we confirm the prognostic impact of POD24 and highlight the relevance of other biomarkers, and we emphasize the importance of novel therapies for patients with high-risk features at first POD.

Histone deacetylase 8 inhibition suppresses mantle cell lymphoma viability while preserving natural killer cell function

Mantle Cell Lymphoma (MCL) is a non-Hodgkin lymphoma with a median survival rate of five years. Standard treatment with high-dose chemotherapy plus rituximab (anti-CD20 antibody) has extended overall survival although, the disease remains incurable. Histone deacetylases (HDAC) are a family of enzymes that regulate multiple proteins and cellular pathways through post-translational modification. Broad spectrum HDAC inhibitors have shown some therapeutic promise, inducing cell cycle inhibition and apoptosis in leukemia and non-Hodgkin's lymphoma. However, the therapeutic effects of these broad-spectrum HDAC inhibitors can detrimentally dampen Natural Killer (NK) cell cytotoxicity, reduce NK viability, and downregulate activation receptors important for NK mediated anti-tumor responses. Impairment of NK function in MCL patients during therapy potentially limits therapeutic activity of rituximab. Thus, there is an unmet need to decipher specific roles of individual HDACs in order to preserve and/or enhance NK function, while, directly impairing MCL viability. We investigated the impact of HDAC8 in MCL cell lines. Inhibition or genetic loss of HDAC8 caused MCL cells to undergo apoptosis. In contrast, exposure of primary human NK cells to an HDAC8 inhibitor does not alter viability, receptor expression, or antibody dependent cellular cytotoxicity (ADCC). However, an increase in effector cytokine interferon-gamma (IFNγ) producing NK cells was observed in response to HDAC8 inhibition. Taken together these data suggest that selective HDAC8 inhibitors may simultaneously preserve NK functional activity, while impairing MCL tumor growth, establishing a rationale for future clinical evaluation.

Survival Trends in Patients Under Age 65 Years With Mantle Cell Lymphoma, 1995-2016: A SEER-Based Analysis

Purpose: The treatment paradigm for mantle cell lymphoma (MCL), a B-cell malignancy, has shifted considerably during the past decades. This study aimed to evaluate time trends in overall survival (OS) and disease-specific mortality (DSM) of younger (age ≤ 65 years) patients with MCL from 1995 to 2016.

Methods: We used the Surveillance, Epidemiology, and End Results database. Year of diagnosis was divided into three eras: the chemotherapy-alone era (1995–2000), intensified-immunochemotherapy era (2001–2012), and targeted-therapy era (2013–2016). We used the Kaplan–Meier method, log-rank test, and subdistribution proportional hazard regression in the analysis.

Results: A total 4,892 patients were identified. Median OS increased from 67 months in the chemotherapy-alone era to 107 months in the intensified-immunochemotherapy era (P < 0.001). The DSM rate decreased significantly from 1995 to 2016 (P < 0.001); the adjusted hazard ratios of MCL-specific death were 0.589 (P < 0.001) for the intensified-immunochemotherapy era and 0.459 (P < 0.001) for targeted-therapy era, as compared with the chemotherapy-alone era. Patients with advanced-stage MCL exhibited lowering risk of death across the three eras (P < 0.001).

Conclusions: During 1995–2016, survival in younger patients with MCL increased significantly, especially those with advanced-stage disease, potentially reflecting the impact of advancement in treatment modalities on MCL outcome.

A Phase III study of zanubrutinib plus rituximab versus bendamustine plus rituximab in transplant-ineligible, untreated mantle cell lymphoma

Mantle cell lymphoma is an aggressive B-cell malignancy. Current frontline chemoimmunotherapies produce high response rates but relapse is inevitable. Furthermore, the elderly and those with comorbidities are precluded from standard regimens and stem cell transplant, leaving them with limited options. Targeted therapies, including Bruton tyrosine kinase inhibitors, are an effective treatment strategy in mantle cell lymphoma. Zanubrutinib is a potent next-generation Bruton tyrosine kinase inhibitor that has demonstrated complete and sustained Bruton tyrosine kinase occupancy, minimal off-target effects and favorable pharmacokinetic/pharmacodynamic properties. Described herein is an ongoing Phase III study comparing the efficacy and safety of zanubrutinib plus rituximab followed by zanubrutinib monotherapy versus bendamustine plus rituximab followed by observation in transplant-ineligible patients with previously untreated mantle cell lymphoma. Clinical Trial Registration: NCT04002297 (ClinicalTrials.gov).

Management of Mantle Cell Lymphoma in the Era of Novel Oral Agents

Objectives: To discuss (1) recent and emerging data for pharmacological management of untreated and relapsed/refractory (R/R) mantle cell lymphoma (MCL) with agents approved in the United States, (2) important considerations for toxicity monitoring and management, and (3) preliminary data and ongoing studies for agents in MCL-specific clinical trials. Data Sources: PubMed/MEDLINE, EMBASE, Google Scholar, product labeling, National Comprehensive Cancer Network, American Cancer Society, and ClinicalTrials.gov were searched for studies published between January 1, 2017, and January 31, 2020, and key historical trials. Study Selection and Data Extraction: Relevant studies conducted in humans and selected supporting preclinical data were reviewed. Data Synthesis: MCL is a rare but usually aggressive non-Hodgkin lymphoma that most commonly affects the older population. Traditionally, the treatment of MCL has been determined based on transplant eligibility. Newer data suggest that more tolerable frontline therapy may produce outcomes similar to intensive historical induction regimens, possibly precluding fewer patients from autologous stem cell transplant and producing better long-term outcomes in transplant-ineligible patients. In the R/R setting, novel regimens are improving outcomes and changing the landscape of treatment. Relevance to Patient Care and Clinical Practice: This review summarizes and discusses recent and emerging data for management of newly diagnosed and R/R MCL; key supportive care considerations for agents are also discussed. Conclusions: Recent study results are changing management of MCL. Although these data have complicated the picture of regimen selection, increasingly effective and tolerable therapy and additional anticipated data point to a brighter future for patients with MCL.

Saudi Lymphoma Group's Clinical Practice Guidelines for Diagnosis, Management and Follow-up of Patients with Various Types of Lymphoma during the Coronavirus Disease 2019 Pandemic

The Saudi Lymphoma Group had previously published recommendations on the management of the major subtypes of lymphoma. However, the effect the currently ongoing coronavirus disease 2019 (COVID-19) pandemic has on the management of patients with lymphoma has been paramount. Therefore, the Saudi Lymphoma Group has decided to provide clinical practice guidelines for the diagnosis, management and follow-up of patients with various types of lymphoma during the COVID-19 pandemic.

Key Clinical and Translational Research Questions to Address Unmet Needs in Mantle Cell Lymphoma

Survival for patients with mantle cell lymphoma has improved dramatically over the last 2 decades owing to a better understanding of disease biology and the development of more effective treatment regimens for patients with untreated and relapsed disease. With these advancements, we are now poised to ask questions that challenge old treatment strategies, use new technologies, and improve our understanding of disease heterogeneity. This article focuses on questions that we believe will drive the future of mantle cell lymphoma treatment. Although not an exhaustive list, we review current literature, ongoing studies, and provide expert opinion on future trial design.

Blastoid Mantle Cell Lymphoma

Blastoid and pleomorphic mantle cell lymphoma (MCL) are among the worst prognostic, aggressive histology, high-risk variants of MCL, and, in this article, they are presented as blastoid MCL. Blastoid MCL have not been systematically studied, probably due to their rarity. De novo blastoid MCLs have superior outcomes compared with transformed MCL. Compared with classic MCL, extranodal involvement (mainly skin, central nervous system), frequent relapses, and inferior responses to conventional chemoimmunotherapy, BTK inhibitors and venetoclax are frequent in blastoid MCL. KTE-X19 induces excellent response in blastoid MCL. Combinations with novel agents are actively investigated. This article presents a comprehensive review on blastoid MCL in 2020.