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

Design, synthesis, and biological evaluation of novel BTK-targeting proteolysis targeting chimeras (PROTACs) with enhanced pharmacokinetic properties

Bruton's tyrosine kinase (BTK) has been an attractive target in the B-cell malignancies. Significant progress has been achieved in developing effective BTK-targeting small-molecule inhibitors and proteolysis targeting chimeras (PROTACs). Based on noncovalent inhibitor ARQ-531, we previously developed two potent BTK PROTACs 6e and SC-3e, which exhibited poor pharmacokinetic property. Herein, we present our extensive structure-activity relationship (SAR) studies focused on BTK binder, linker and cereblon (CRBN) ligand of SC-3e, resulting in two novel BTK PROTACs FDU28 (compound 25) and FDU73 (compound 27). Compounds 25 and 27 selectively induced rapid and robust degradation of wild type (WT) and C481S mutant BTK in a concentration-, time- and ubiquitin-proteasome system (UPS)-dependent manner without affecting CRBN neo-substrates. Furthermore, compound 27 displayed excellent cell antiproliferative activities, metabolic stability in mouse liver microsomes and improved bioavailability in mice. Overall, 27 is a highly effective and selective BTK degrader that is suitable for in vivo efficacy investigations.

Prognostic risk factors of pneumonia associated with COVID-19 in patients with lymphoma

Objective

Patients with hematological malignancies have an elevated risk of developing pneumonia after contracting COVID-19. Lymphoma is the most prevalent hematologic malignancy. It is critical to identify patients at high risk of contracting COVID-19-associated pneumonia.

Methods

From January 11-31, 2023, we distributed questionnaires to patients diagnosed with lymphoma according to 2016 World Health Organization diagnostic and classification criteria. COVID-19 infection was confirmed based on symptoms and laboratory tests. Pneumonia was confirmed using computed tomography scans.

Results

In total, 257 patients were included in this study; 221 patients (86.0%) had COVID-19 infection and 61 (27.6%) of these had pneumonia. Patients with B-cell non-Hodgkin lymphoma (B-NHL) had a significantly higher pneumonia incidence than patients with other lymphoma types (31.8% vs. 27.6%, P=0.005). Higher incidence of pneumonia was observed in patients receiving anti-CD20 therapy (30.0% vs. 16.3%, P=0.048) and Bruton's tyrosine kinase (BTK) inhibitor therapy (51.3% vs. 22.5%, P=0.001). B-NHL (hazard ratio [HR]=3.7, 95% confidence interval [CI] 1.4-10.0, P=0.009), anti-CD20 therapy (HR=2.3, 95% CI 1.0-5.2, P=0.050), BTK inhibitor (HR=3.6, 95% CI 1.8-7.4, P<0.001), active therapy (HR=3.0, 95% CI 1.5-5.7, P=0.001), and lack of disease remission (HR=3.7, 95% CI 1.8-7.4, P=0.001) were high-risk factors for developing pneumonia. Anti-PD-1 therapy was a protective factor against pneumonia development (HR=0.2, 95% CI 0.05-0.9, P=0.034). In multivariable analysis, BTK inhibitor (HR=3.5, 95% CI 1.6-8.0, P=0.003), active therapy (HR=3.3, 95% CI 1.6-6.8, P=0.001), and disease non-remission (HR=2.9, 1.3-6.4, P=0.007) were independent risk factors for pneumonia development after COVID-19 infection in patients with lymphoma.

Conclusions

Patients with lymphoma receiving BTK inhibitors, undergoing active therapy, and lacking disease remission exhibited a higher risk for pneumonia associated with COVID-19.

Navigating the changing landscape of BTK-targeted therapies for B cell lymphomas and chronic lymphocytic leukaemia

The B cell receptor (BCR) signalling pathway has an integral role in the pathogenesis of many B cell malignancies, including chronic lymphocytic leukaemia, mantle cell lymphoma, diffuse large B cell lymphoma and Waldenström macroglobulinaemia. Bruton tyrosine kinase (BTK) is a key node mediating signal transduction downstream of the BCR. The advent of BTK inhibitors has revolutionized the treatment landscape of B cell malignancies, with these agents often replacing highly intensive and toxic chemoimmunotherapy regimens as the standard of care. In this Review, we discuss the pivotal trials that have led to the approval of various covalent BTK inhibitors, the current treatment indications for these agents and mechanisms of resistance. In addition, we discuss novel BTK-targeted therapies, including covalent, as well as non-covalent, BTK inhibitors, BTK degraders and combination doublet and triplet regimens, to provide insights on the best current treatment paradigms in the frontline setting and at disease relapse.

Advancements in B-Cell Non-Hodgkin's Lymphoma: From Signaling Pathways to Targeted Therapies

Lymphoma is the sixth most prevalent cancer globally. Non-Hodgkin's lymphomas are the majority group of lymphomas, with B cells accounting for approximately 95% of these lymphomas. A key feature of B-cell lymphoma is the functional perturbations of essential biological pathways caused by genetic aberrations. These lead to atypical gene expression, providing cells with a selective growth advantage. Molecular analysis reveals that each lymphoma subtype has unique molecular mutations, which pose challenges in disease management and treatment. Substantial efforts over the last decade have led to the integration of this information into clinical applications, resulting in crucial insights into clinical diagnosis and targeted therapies. However, with the growing need for more effective medication development, we anticipate a deeper understanding of signaling pathways and their interactions to emerge. This review aims to demonstrate how the BCR, specific signaling pathways like PI3K/AKT/mTOR, NF-kB, and JAK/STAT are diverse in common types of B-cell lymphoma. Furthermore, it offers a detailed examination of each pathway and a synopsis of the approved or in-development targeted therapies. In conclusion, finding the activated signaling pathways is crucial for developing effective treatment plans to improve the prognosis of patients with relapsed or refractory lymphoma. Trial Registration: ClinicalTrials.gov identifier: NCT02180724, NCT02029443, NCT02477696, NCT03836261, NCT02343120, NCT04440059, NCT01882803, NCT01258998, NCT01742988, NCT02055820, NCT02285062, NCT01855750, NCT03422679, NCT01897571.

Unmet needs in relapsed/refractory mantle cell lymphoma (r/r MCL) post-covalent Bruton tyrosine kinase inhibitor (BTKi): a systematic literature review and meta-analysis

To quantify the clinical unmet need of r/r MCL patients who progress on a covalent Bruton tyrosine kinase inhibitor (BTKi), we conducted a systematic review to identify studies that reported overall survival (OS), progression-free survival (PFS), or response outcomes of patients who received a chemo(immunotherapy) ± targeted agent standard therapy (STx) or brexucabtagene autoleucel (brexu-cel) in the post-BTKi setting. Twenty-six studies (23 observational; three trials) reporting outcomes from 2005 to 2022 were included. Using two-stage frequentist meta-analyses, the estimated median PFS/OS for patients treated with an STx was 7.6 months (95% CI: 3.9-14.6) and 9.1 months (95% CI: 7.3-11.3), respectively. The estimated objective response rate (ORR) was 45% (95% CI: 34-57%). For patients treated with brexu-cel, the estimated median PFS/OS was 14.9 months (95% CI: 10.5-21.0) and 32.1 months (95% CI: 25.2-41.2), with a pooled ORR of 89% (95% CI: 86-91%). Our findings highlight a significant unmet need for patients whose disease progresses on a covalent BTKi.

Management of relapsed/refractory mantle cell lymphoma

In this review we summarize the current evidence describing the management of patients with relapsed/refractory MCL and outline the various novel therapeutics that have been developed over the past two decades. We also describe how overall response rates, complete response rates, duration of responses, and life expectancy have dramatically increased with the introduction of novel therapies, particularly covalent Bruton Tyrosine Kinase inhibitors (BTKi) and chimeric antigen receptor T-cell (CAR-T) therapy. The most recent emerging options for patients with progressive disease following BTKi or CAR-T, including non-covalent BTKi, antibody-drug conjugates, Bcl-2 inhibitors, and bispecific antibodies, may further improve response rates and outcomes. Future directions should focus on identifying the best sequencing and/or combinations of the increasingly available treatment options while prioritizing strategies with curative potential.

Use of new and emerging cancer drugs: what the cardiologist needs to know

The last decade has witnessed a paradigm shift in cancer therapy, from non-specific cytotoxic chemotherapies to agents targeting specific molecular mechanisms. Nonetheless, cardiovascular toxicity of cancer therapies remains an important concern. This is particularly relevant given the significant improvement in survival of solid and haematological cancers achieved in the last decades. Cardio-oncology is a subspecialty of medicine focusing on the identification and prevention of cancer therapy-related cardiovascular toxicity (CTR-CVT). This review will examine the new definition of CTR-CVT and guiding principles for baseline cardiovascular assessment and risk stratification before cancer therapy, providing take-home messages for non-specialized cardiologists.

Drug-induced atrial fibrillation. A narrative review of a forgotten adverse effect

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with an increased morbidity and mortality. There is clinical evidence that an increasing number of cardiovascular and non-cardiovascular drugs, mainly anticancer drugs, can induce AF either in patients with or without pre-existing cardiac disorders, but drug-induced AF (DIAF) has not received the attention that it might deserve. In many cases DIAF is asymptomatic and paroxysmal and patients recover sinus rhythm spontaneously, but sometimes, DIAF persists, and it is necessary to perform a cardioversion. Furthermore, DIAF is not mentioned in clinical guidelines on the treatment of AF. The risk of DIAF increases in elderly and in patients treated with polypharmacy and with risk factors and comorbidities that commonly coexist with AF. This is the case of cancer patients. Under these circumstances ascribing causality of DIAF to a given drug often represents a clinical challenge. We review the incidence, the pathophysiological mechanisms, risk factors, clinical relevance, and treatment of DIAF. Because of the limited information presently available, further research is needed to obtain a deeper insight into DIAF. Meanwhile, it is important that clinicians are aware of the problem that DIAF represents, recognize which drugs may cause DIAF, and consider the possibility that a drug may be responsible for a new-onset AF episode.

Zanubrutinib-lenalidomide-rituximab (ZR2) in unfit diffuse large B-cell lymphoma: efficient and tolerant

The objective of this study is to examine the effectiveness and safety of zanubrutinib, rituximab, and lenalidomide (ZR2) in unfit patients with diffuse large B-cell lymphoma (DLBCL). Thrombosis or bleeding risk of ZR2 regimen, especially when antiplatelet agents were co-prescribed, was also evaluated. We retrospectively reviewed unfit newly diagnosed (ND) and refractory or relapsed (R/R) patients with DLBCL who were administered with ZR2 regimen in two medical centers between December 2019 and February 2022. Response rates, progression-free survival (PFS), overall survival (OS), bleeding adverse events (AEs), and thrombosis episodes were analyzed. Furthermore, we investigated the effects of zanubrutinib alone or in combination with lenalidomide on platelet functions in vitro and in vivo. A total of 30 unfit patients (13 ND DLBCL and 17 R/R DLBCL patients) who received ZR2 regimen were enrolled in the study (median age: 69.5 years). The ultimate ORRs for the ND DLBCL and R/R DLBCL were 77.0% and 50.1%, respectively. The median follow-up was 16.6 months. The median PFS and OS were not achieved during the follow-up time. Subcutaneous hemorrhage AEs occurred in four cases, three cases suffered severe bleeding events, and thrombosis events were observed in two patients. ZR2 regimen inhibited platelet functions (aggregation, clot retraction, spreading and activation) in vitro and in vivo function testing especially in response to collagen. ZR2 is an efficient treatment option for unfit patients with DLBCL and could be well tolerated. Notably, this regimen inhibited platelet functions. Antiplatelet agents should be used with caution in patients treated with this regimen.

Final results and overall survival data from a phase II study of acalabrutinib monotherapy in patients with relapsed/refractory mantle cell lymphoma, including those with poor prognostic factors

Not available.

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.

Combined therapy with ibrutinib and bortezomib followed by ibrutinib maintenance in relapsed or refractory mantle cell lymphoma and high-risk features: a phase 1/2 trial of the European MCL network (SAKK 36/13)

Background

The Bruton's tyrosine kinase inhibitor ibrutinib and the proteasome inhibitor bortezomib have single-agent activity, non-overlapping toxicities, and regulatory approval in mantle cell lymphoma (MCL). In vitro, their combination provides synergistic cytotoxicity. In this investigator-initiated phase 1/2 trial, we established the recommended phase 2 dose of ibrutinib in combination with bortezomib, and assessed its efficacy in patients with relapsed or refractory MCL.

Methods

In this phase 1/2 study open in 15 sites in Switzerland, Germany and Italy, patients with relapsed or refractory MCL after ≤2 lines of chemotherapy and both ibrutinib-naïve and bortezomib-naïve received six cycles of ibrutinibb and bortezomib, followed by ibrutinib maintenance. For the phase 1 study, a standard 3 + 3 dose escalation design was used to determine the recommended phase 2 dose of ibrutinib in combination with bortezomib. The primary endpoint in phase 1 was the dose limiting toxicities in cycle 1. The phase 2 study was an open-label, single-arm trial with a Simon's two-stage min-max design, with a primary endpoint of overall response rate (ORR) assessed by CT/MRI. This study was registered with ClinicalTrials.gov, NCT02356458.

Findings

Between August 2015 and September 2016, nine patients were treated in the phase 1 study, and 49 patients were treated between November 2016 and March 2020 in the phase 2 of the trial. The ORR was 81.8% (90% CI 71.1, 89.8%, CR(u) 21.8%) which increased with continued ibrutinib (median 10.6 months) to 87.3%, (CR(u) 41.8%). 75.6% of patients had at least one high-risk feature (Ki-67 > 30%, blastoid or pleomorphic variant, p53 overexpression, TP53 mutations and/or deletions). In these patients, ibrutinib and bortezomib were also effective with an ORR of 74%, increasing to 82% during maintenance. With a median follow-up of 25.4 months, the median duration of response was 22.7, and the median PFS was 18.6 months. PFS reached 30.8 and 32.9 months for patients with a CR or Cru, respectively.

Interpretation

The combination of ibrutinib and bortezomib shows durable efficacy in patients with relapsed or refractory MCL, also in the presence of high-risk features.

Funding

SAKK (Hubacher Fund), Swiss State Secretariat for Education, Research and Innovation, Swiss Cancer Research Foundation, and Janssen.

Combating relapsed and refractory Mantle cell lymphoma with novel therapeutic armamentarium: Recent advances and clinical prospects

Mantle cell lymphoma (MCL) is a rare, aggressive subtype of non-Hodgkin's lymphoma (NHL), accounting for 5% of all cases. Due to its virulence factor, it is an incurable disease and keeps relapsing despite an intensive treatment regimen. Advancements in research and drug discovery have shifted the treatment strategy from conventional chemotherapy to targeted agents and immunotherapies. The establishment of the role of Bruton tyrosine kinase led to the development of ibrutinib, a first-generation BTK inhibitor, and its successors. A conditioning regimen based immunotherapeutic agent like ibritumumob, has also demonstrated a viable response with a favorable toxicity profile. Brexucabtagene Autoleucel, the only approved CAR T-cell therapy, has proven advantageous for relapsed/refractory MCL in both children and adults. This article reviews certain therapies that could help update the current approach and summarizes a few miscellaneous agents, which, seldom studied in trials, could alleviate the regression observed in traditional therapies. DATA AVAILABILITY: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Zanubrutinib: past, present, and future

In recent years, Bruton tyrosine kinase (BTK) inhibitors have provided significant advances in the treatment of patients with B-cell malignancies. Ibrutinib was the first BTK inhibitor to be approved, and it changed the standard-of-care treatment for diseases such as chronic lymphocytic leukemia, mantle cell lymphoma, marginal zone lymphoma, and Waldenström macroglobulinemia, improving efficacy outcomes and safety compared to chemotherapy. In this article, we review the development of zanubrutinib, a next-generation BTK inhibitor, from molecular design to patient-related outcomes. We start this journey by providing insights into the discovery of BTK and the physiologic, genetic, and molecular characterization of patients lacking this kinase, together with the brief treatment landscape in the era of chemo-immunotherapies. Zanubrutinib was originally developed by applying a structure-activity strategy to enhance the specificity as well as enzymatic and pharmacokinetic properties. Preclinical studies confirmed greater specificity and better bioavailability of zanubrutinib compared with that of ibrutinib, which supported the initiation of clinical trials in humans. Preliminary clinical results indicated activity in B-cell malignancies together with an improved safety profile, in line with less off-target effects described in the preclinical studies. The clinical program of zanubrutinib has since expanded significantly, with ongoing studies in a wide range of hemato-oncological diseases and in combination with many other therapies. Zanubrutinib currently is approved for various B-cell malignancies in multiple countries. This story highlights the importance of multidisciplinary collaborative research, from bench to bedside, and provides an example of how the commitment to finding improved treatment options should always run parallel to patient care.

Clinical outcome of Mantle Cell Lymphoma patients with high-risk disease (high-risk MIPI-c or high p53 expression)

Currently, treatment allocation of patients with Mantle Cell Lymphoma (MCL) is mainly based on age and medical fitness. The combined MCL International Prognostic Index (MIPI-c) allows to predict prognosis using clinical factors (MIPI) and the Ki-67 index. However, high p53 expression as surrogate for TP53 alterations has demonstrated to be an independent predictor for poor outcome. We aimed to define a clear high-risk group based on the combination of MIPI, Ki-67 and p53 expression/TP53 alteration. A total of 684 patients from the prospective European MCL-Younger and MCL-Elderly trials were evaluable. The classification of high-risk disease (HRD) as high-risk MIPI-c or p53 expression >50% versus low-risk disease (LRD) as low, low-intermediate or high-intermediate MIPI-c and p53 expression ≤50% allowed to characterize two distinct groups with highly divergent outcome. Patients with HRD had significantly shorter median failure-free survival (FFS) (1.1 vs. 5.6 years, p < 0.0001) and overall survival (OS) (2.2 vs. 13.2 years, p < 0.0001) compared to those with LRD. These major differences were confirmed in two validation cohorts from the Italian MCL0208 and the Nordic-MCL4 trials. The results suggest that this subset of HRD patients is not sufficiently managed with the current standard treatment and is asking for novel treatment strategies.

Long-term outcomes of second-line versus later-line zanubrutinib treatment in patients with relapsed/refractory mantle cell lymphoma: An updated pooled analysis

BACKGROUND

We previously reported results of a pooled analysis of two zanubrutinib studies in relapsed or refractory (R/R) MCL showing better survival outcomes when zanubrutinib is used in second-line versus later-line. Here, we present an updated pooled analysis with a longer follow-up of 35.2 months.

METHODS

Data were pooled from two studies-BGB-3111-AU-003 (NCT02343120) and BGB-3111-206 (NCT03206970) of zanubrutinib in R/R MCL. The patients were divided into two groups based on the treatment line of zanubrutinib: the second-line and the later-line group. The inverse propensity score weighting method was used to balance the baseline covariates between the groups. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), PFS, and OS rates, objective response rate (ORR), duration of response (DOR), and safety.

RESULTS

Among 112 pooled patients, 41 (36.6%) patients received zanubrutinib as second-line and 71 (63.4%) patients as later-line therapy. After weighting, OS was significantly improved in the second-line versus later-line group (HR, 0.459 [95% CI: 0.215, 0.98]; p = 0.044) with median OS not estimable in both groups. The PFS was similar between the two groups (HR, 0.78 [95% CI: 0.443, 1.373]; p = 0.389) but with numerically longer median PFS in the second-line versus later-line group (27.8 vs. 22.1 months). ORR was numerically higher in the second-line versus later-line (88.6% vs. 85.7%), and DOR was similar between the two groups (25.2 vs. 25.1 months). Zanubrutinib showed a similar safety profile in both groups.

CONCLUSION

Zanubrutinib in second-line treatment was associated with significantly improved OS compared with later-line treatment of R/R MCL.

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.

Orelabrutinib for the treatment of relapsed or refractory MCL: a phase 1/2, open-label, multicenter, single-arm study

Relapsed or refractory (r/r) mantle cell lymphoma (MCL) is an aggressive B-cell malignancy with a poor prognosis. Bruton tyrosine kinase (BTK) is a mediator of B-cell receptor signaling and is associated with the development of B-cell lymphomas. Patients with r/r MCL were enrolled in this phase 1/2 study and treated with orelabrutinib, a novel, highly selective BTK inhibitor. The median number of prior regimens was 2 (range, 1-4). The median age was 62 years (range, 37-73 years). Eligible patients received oral orelabrutinib 150 mg once daily (n = 86) or 100 mg twice daily (n = 20) until disease progression or unacceptable toxicity. A dose of 150 mg once daily was chosen as the preferred recommended phase 2 dose. After a median follow-up duration of 23.8 months, the overall response rate was 81.1%, with 27.4% achieving a complete response and 53.8% achieving a partial response. The median duration of response and progression-free survival were 22.9 and 22.0 months, respectively. The median overall survival (OS) was not reached, and the rate of OS at 24 months was 74.3%. Adverse events (AEs) occurring in >20% of patients were thrombocytopenia (34.0%), upper respiratory tract infection (27.4%), and neutropenia (24.5%). Grade ≥3 AEs were infrequent and most commonly included thrombocytopenia (13.2%), neutropenia (8.5%), and anemia (7.5%). Three patients discontinued treatment because of treatment-related adverse events (TRAEs), but no fatal TRAEs were reported. Orelabrutinib showed substantial efficacy and was well tolerated in patients with r/r MCL. This trial was registered at www.clinicaltrials.gov as #NCT03494179.

Hepatotoxicity of Small Molecule Protein Kinase Inhibitors for Cancer

Small molecule protein kinase inhibitors (PKIs) have become an effective strategy for cancer patients. However, hepatotoxicity is a major safety concern of these drugs, since the majority are reported to increase transaminases, and few of them (Idelalisib, Lapatinib, Pazopanib, Pexidartinib, Ponatinib, Regorafenib, Sunitinib) have a boxed label warning. The exact rate of PKI-induced hepatoxicity is not well defined due to the fact that the majority of data arise from pre-registration or registration trials on fairly selected patients, and the post-marketing data are often based only on the most severe described cases, whereas most real practice studies do not include drug-related hepatotoxicity as an end point. Although these side effects are usually reversible by dose adjustment or therapy suspension, or by switching to an alternative PKI, and fatality is uncommon, all patients undergoing PKIs should be carefully pre-evaluated and monitored. The management of this complication requires an individually tailored reappraisal of the risk/benefit ratio, especially in patients who are responding to therapy. This review reports the currently available data on the risk and management of hepatotoxicity of all the approved PKIs.

Case report: CD19-directed CAR-T cell therapy combined with BTK inhibitor and PD-1 antibody against secondary central nervous system lymphoma

Current therapeutic strategies for central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) are extremely limited. Secondary central nervous system lymphoma (SCNSL) also shows a grave prognosis and high mortality. This report describes a young female patient with DLBCL and CNS relapse who received low-dose CD19-directed chimeric antigen receptor T (CAR-T) cell therapy followed with Bruton’s tyrosine kinase inhibitor and programmed cell death protein 1 antibody after several lines of chemotherapy. However, limited reports on CAR-T cell therapy are applied for SCNSL, particularly those in combination with targeted agents. The current treatment combination for this case provides a new regimen for CNS relapse from DLBCL.

Zanubrutinib Monotherapy for Naïve and Relapsed/Refractory Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma: A Pooled Analysis of Three Studies

INTRODUCTION

Zanubrutinib is a highly selective irreversible inhibitor of Bruton tyrosine kinase which has shown significant activity in lymphoid malignancies in early phase studies. We report here the long-term follow-up outcomes of zanubrutinib in various lines of therapy in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL).

METHODS

This post hoc analysis pooled patients with treatment-naïve (TN) or relapsed/refractory (R/R) CLL/SLL receiving zanubrutinib monotherapy from three phase 1/2 studies (BGB-3111-1002, BGB-3111-AU-003, BGB-3111-205).

RESULTS

A total of 211 patients with CLL/SLL (TN 19, R/R 192) were included. After weighting (TN 19, R/R 24), the overall response rate (ORR) was 95.4% and significantly higher in the TN group than in the R/R group (100 vs. 91.0%, p < 0.0001). ORR was also significantly higher in the TN group than in the one prior line of therapy group (100 vs. 98.9%, p < 0.0001). Among those with R/R disease, the ORR was 97.8% in patients with one prior line of therapy (n = 79) and 90.7% in those with > 1 prior lines of therapy (n = 85; p = 0.080). The median follow-up times were 50.1, 35.7, and 45.9 months for TN, R/R and all cohorts, respectively. Progression-free survival and overall survival were significantly longer in the TN group and only one prior line of therapy group compared with the > 1 prior lines of therapy group (all p < 0.05) and were similar in the TN group compared with the one prior line therapy group. Efficacy was similar regardless of the presence of genomic aberrations. Most frequent grade ≥ 3 adverse events were infections (41.7%), neutropenia (34.1%), and thrombocytopenia (9.4%). Atrial fibrillation occurred in only 1.9% of patients.

CONCLUSIONS

With extended follow-up, zanubrutinib yielded long-term benefits and demonstrated a favorable safety profile for patients with TN or RR CLL/SLL. Earlier utilization of zanubrutinib was associated with better outcomes.

TRIAL REGISTRATION

Clinical Trials.gov identifiers, NCT03189524, NCT02343120 (retrospectively registered), and NCT03206918 (retrospectively registered).

Ibrutinib-Associated Cardiotoxicity: From the Pharmaceutical to the Clinical

Ibrutinib is the first-in-class Bruton tyrosine kinase (BTK) inhibitor that has revolutionized the treatment of B cell malignancies. Unfortunately, increased incidences of cardiotoxicity have limited its use. Despite over a decade of research, the biological mechanisms underlying ibrutinib cardiotoxicity remain unclear. In this review, we discuss the pharmacological properties of ibrutinib, the incidence and mechanisms of ibrutinib-induced cardiotoxicity, and practical management to prevent and treat this condition. We also synopsize and discuss the cardiovascular adverse effects related to other more selective BTK inhibitors, which may guide the selection of appropriate BTK inhibitors.

Case Report: Dual Inhibition of HDAC and BTK for Diffuse Large B-Cell Lymphoma After Failure to CD19-Targeted CAR-T Therapy

Background

Failure to CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), is an emerging clinical problem. There is no consensus on the treatment for these patients and treatment remains empirical.

Case Report

We reported a case of an elderly R/R DLBCL patient who had TP53 mutation and relapsed 12 months after initial response to CAR T-cell therapy. The patient did not respond to salvage chemotherapy with the GDP regimen and could not tolerate any aggressive chemotherapy. Thereafter, the patient was given chidamide and zanubrutinib. After two months of treatment, the patient achieved sustained complete remission. At the last follow-up, the patient remains in radiographic CR 22 months after CAR-T infusion and 10 months after the initiation of the combination treatment.

Conclusion

We report the first successful case of dual inhibition of HDAC and BTK for the treatment of R/R DLBCL after failure to CAR-T cell therapy, which opens a new therapeutic possibility for the future.

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.

Zanubrutinib in lymphoproliferative disorders: a comprehensive review

The availability of Bruton tyrosine kinase (BTK) inhibitors has brought about a paradigm shift in the treatment of patients with B-cell lymphomas and chronic lymphocytic leukemia. BTK was clinically validated as a target by the efficacy of the first-in-class inhibitor ibrutinib. The extended survival conferred by BTK inhibitors has brought long-term tolerability to the foreground. To minimize toxicities thought to be attributable to off-target kinase inhibition, a next generation of BTK inhibitors with greater selectivity was developed. In the United States, zanubrutinib, a next-generation BTK inhibitor, has been approved for treating adults with mantle cell lymphoma who have received at least one prior therapy, for adults with Waldenström macroglobulinemia, and for adults with relapsed or refractory marginal zone lymphoma who have received at least one anti-CD20-based therapy. Because few head-to-head comparative trials of BTK inhibitors have so far been reported, no BTK 'inhibitor of choice' can be identified. Zanubrutinib has promising efficacy in its approved indications and appears to have reduced cardiac toxicities, particularly atrial fibrillation, which may influence the choice of BTK inhibitor treatment by prescribers. Further studies are needed to inform on optimal treatment sequencing of zanubrutinib and its combination with other agents. Here, we summarize existing clinical evidence for its efficacy and safety in mantle cell lymphoma, Waldenström macroglobulinemia, marginal zone lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma, and other B-lymphoproliferative indications.

Plain Language Summary

Zanubrutinib is a drug that was shown to effectively treat cancer of B cells without causing excessive serious side effects Patients with certain B-cell malignancies (cancers of white blood cells) benefit from treatment with Bruton tyrosine kinase (BTK) inhibitors, drugs that block the BTK protein and keep cancer from growing and spreading. Patients experience extended survival with ibrutinib, the first-generation BTK inhibitor approved by US Food and Drug Administration (FDA); however, one in five patients quit treatment because of harmful side effects. Ibrutinib-related side effects such as increased risk of bleeding, atrial fibrillation (abnormal heart rhythm), and high blood pressure are thought to be caused by ibrutinib blocking other proteins besides the intended target protein BTK. To reduce these side effects, zanubrutinib, a next-generation BTK inhibitor, was designed to block BTK more specifically than ibrutinib. Results of clinical studies on zanubrutinib treatment appear promising in patients with several types of B-cell malignancies, including mantle cell lymphoma (MCL), Waldenström macroglobulinemia (WM), marginal zone lymphoma (MZL), chronic lymphocytic leukemia, and small lymphocytic lymphoma. There are not yet enough clinical data to determine which BTK inhibitor is most effective in treating B-cell malignancies without causing harmful side effects. Early data from the phase 3 ALPINE clinical study suggest that zanubrutinib works better than ibrutinib, and fewer patients experience side effects and quit treatment. Zanubrutinib is currently approved for use for treatment of adult patients with MCL who have received at least one prior therapy, for adults with WM, and for adults with MZL who have received at least one anti-CD20-based therapy.

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.