Targets for Ibrutinib Beyond B Cell Malignancies

Chemoselective Stabilized Triphenylphosphonium Probes for Capturing Reactive Carbonyl Species and Regenerating Covalent Inhibitors with Acrylamide Warheads in Cellulo

Reactive carbonyl species (RCS) are important biomarkers of oxidative stress-related diseases because of their highly reactive electrophilic nature. Despite their potential as triggers for prodrug activation, selective labeling approaches for RCS remain limited. Here, we utilized triphenylphosphonium groups to chemoselectively capture RCS via an aqueous Wittig reaction, forming α,β-unsaturated carbonyls that enable further functionalization. We first designed native (light) and deuterated (heavy) probes to facilitate RCS metabolomic identification through distinct MS isotope patterns. This approach allowed us to capture and relatively quantify several endogenous RCS related to advanced lipoxidation/glycation end products (ALEs/AGEs). Second, we demonstrated that various endogenous RCS can trigger the in situ generation of acrylamide warheads of targeted covalent inhibitors (TCIs) with different substituents. These structural variations influence their protein binding profiles and consequently alter their cytotoxicity, which is beneficial for the development of inhibitor cocktails.

Sequelae of B-Cell Depleting Therapy: An Immunologist's Perspective

B-cell depleting therapy (BCDT) has revolutionised the treatment of B-cell malignancies and autoimmune diseases by targeting specific B-cell surface antigens, receptors, ligands, and signalling pathways. This narrative review explores the mechanisms, applications, and complications of BCDT, focusing on the therapeutic advancements since the introduction of rituximab in 1997. Various monoclonal antibodies and kinase inhibitors are examined for their roles in depleting B cells through antibody-dependent and independent mechanisms. The off-target effects, such as hypogammaglobulinemia, infections, and cytokine release syndrome, are discussed, emphasising the need for immunologists to identify and help manage these complications. The increasing prevalence of BCDT has necessitated the involvement of clinical immunologists in addressing treatment-associated immunological abnormalities, including persistent hypogammaglobulinemia and neutropenia. We highlight the importance of considering underlying inborn errors of immunity (IEI) in patients presenting with these complications. Furthermore, we discuss the impact of BCDT on other immune cell populations and the challenges in predicting and managing long-term immunological sequelae. The potential for novel BCDT agents targeting the BAFF/APRIL-TACI/BCMA axis and B-cell receptor signalling pathways to treat autoimmune disorders is also explored, underscoring the rapidly evolving landscape of B-cell targeted therapies.

[Cardiovascular adverse effects of Bruton tyrosine kinase inhibitors: Pathophysiological mechanisms, screening, and management]

The covalent Bruton tyrosine kinase inhibitors (iBTKs) have profoundly transformed the management of B-cell lymphoid malignancies, particularly chronic lymphocytic leukemia (CLL). These targeted therapies, with ibrutinib as the pioneer, have paved the way for significant improvement in the prognosis of many patients. With second-generation iBTKs such as acalabrutinib and zanubrutinib, the therapeutic landscape has expanded, offering potential new options for patients with CLL. This review focuses on the cardiovascular adverse effects associated with these treatments. It delves into the underlying pathophysiological mechanisms of these effects, highlighting the complex interactions between these molecules and the cardiovascular system. Additionally, it examines the frequency of adverse effects according to the type of iBTK, drawing on data from clinical trials and real-world clinical practice. Finally, the importance of close cardio-oncological monitoring is emphasized, with essential collaboration between hematologists and cardiologists. Strategies for screening and managing cardiovascular adverse effects are also discussed, emphasizing the need for a proactive approach in managing these complications. Experts propose a pragmatic follow-up of these patients, through a central illustration and a figure adapted from European cardio-oncology guidelines, to simplify hematologists' practice.

Efficacy and Safety of Ibrutinib as Monotherapy or Combination Therapy in Relapsed/Refractory Diffuse Large B-cell Lymphoma (R/R DLBCL): A Systematic Review and Meta-analysis

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a highly heterogeneous disease group. Ibrutinib's monotherapy or combination therapy is effective in relapsed/refractory (R/R) DLBCL. However, the treatment response in R/R DLBCL varies from 15% to 90% with different regimens, and the tolerance remains controversial.

AREAS OF UNCERTAINTY

The efficacy and safety of ibrutinib monotherapy or combination therapy in patients with R/R DLBCL remain uncertain.

DATA SOURCES

The PubMed, CBM, MEDLINE, Cochrane Library, and Embase databases were searched from their inception to July 2021.

THERAPEUTIC ADVANCES

The total complete remission rate (CRR) and overall response rate in R/R DLBCL patients treated with ibrutinib were 26% and 49%, respectively. The CRR of ibrutinib combination therapy was significantly higher than the ibrutinib monotherapy (45% vs. 19%). Moreover, the CRR of patients was 40% in double expressing lymphoma, 35% in central nervous system lymphoma, and 33% in nongerminal center B-cell-like (non-GCB) DLBCL, which was higher than the 8% in those with the GCB subtype. The pooled median PFS and overall survival were 5.57 and 10.17 months, respectively. GCB-DLBCL had the worst overall survival (5.1 months). Nevertheless, we found that combination regimens had no survival advantage compared with monotherapy (P > 0.05), indicating that combination therapy was only a transitional treatment and bridge for chimeric antigen receptor T cells or other treatments. Moreover, 12% of patients on ibrutinib combination therapy had ≥grade 3 adverse events compared with 9% on ibrutinib monotherapy.

CONCLUSIONS

Ibrutinib monotherapy or combination therapy was safe and effective in treating R/R DLBCL with tolerable adverse reactions.

Recent advances in the design of small molecular drugs with acrylamides covalent warheads

In the development of covalent inhibitors, acrylamides warhead is one of the most popular classes of covalent warheads. In recent years, researchers have made different structural modifications to acrylamides warheads, resulting in the creation of fluorinated acrylamide warheads and cyano acrylamide warheads. These new warheads exhibit superior selectivity, intracellular accumulation, and pharmacokinetic properties. Additionally, although ketoamide warheads have been applied in the design of covalent inhibitors for viral proteins, it has not received sufficient attention. Combined with the studies in kinase inhibitors and antiviral drugs, this review presents the structural features and the progression of acrylamides warheads, offering a perspective on future research and development in this field.

Characterization of ibrutinib's effects on the morphology, proliferation, phenotype, viability, and anti-inflammatory potential of adipose-derived mesenchymal stromal cells

Ibrutinib (IB) is a tyrosine kinase inhibitor (TKI) that has immunomodulatory action and can be used as second-line therapy for steroid-refractory or steroid-resistant chronic Graft versus Host Disease (cGVHD). Mesenchymal stromal cells (MSCs) are distributed throughout the body and their infusion has also been explored as a second-line therapeutic alternative for the treatment of cGVHD. Considering the currently unknown effects of IB on endogenous MSCs, as well as the possible combined use of IB and MSCs for cGVHD, we investigated whether adipose tissue-derived MSCs present IB-targets, as well as the consequences of treating MSCs with this drug, regarding cell viability, proliferation, phenotype, and anti-inflammatory potential. Interestingly, we show for the first time that MSCs express several IB target genes. Also of note, the treatment of such cells with this TKI elevated the levels of CD90 and CD105 surface proteins, as well as VCAM-1. Furthermore, IB-treated MSCs presented increased mRNA expression of the anti-inflammatory genes PD-L1, TSG-6, and IL-10. However, continued exposure to IB, even at low doses, compromised the viability of MSCs. These data indicate that the use of IB can stimulate an anti-inflammatory profile in MSCs, but also that a continued exposure to IB can compromise MSC viability over time.

Targeting Bruton's tyrosine kinase (BTK) as a signaling pathway in immune-mediated diseases: from molecular mechanisms to leading treatments

Bruton's tyrosine kinase (BTK), a nonreceptor tyrosine kinase, plays a remarkable role in the transmission and amplification of extracellular signals to intracellular signaling pathways. Various types of cells use the BTK pathway to communicate, including hematopoietic cells particularly B cells and T cells. The BTK pathway plays a role in controlling the proliferation, survival, and functions of B cells as well as other myeloid cells. First, second, and third-generation BTK inhibitors are currently being evaluated for the treatment of immune-mediated diseases in addition to B cell malignancies. In this article, the available evidence on the action mechanisms of BTK inhibitors is reviewed. Then, the most recent data obtained from preclinical studies and ongoing clinical trials for the treatment of autoimmune diseases, such as pemphigus vulgaris, pemphigus foliaceus, bullous pemphigoid, systemic lupus erythematosus, Sjögren's disease, rheumatoid arthritis, systemic sclerosis, multiple sclerosis, myasthenia gravis, and inflammatory diseases such as psoriasis, chronic spontaneous urticaria, atopic dermatitis, and asthma are discussed. In addition, adverse effects and complications associated with BTK inhibitors as well as factors predisposing patients to BTK inhibitors complications are discussed.

Discovery of promising B lymphocyte kinase inhibitors using structure-guided virtual screening

Tyrosine-protein kinase BLK, also known as B-cell lymphocyte kinase (BLK), is a non-receptor tyrosine kinase that is primarily expressed in B-cells. BLK plays a key role in B-cell signaling, particularly in B-cell development and maturation. The increased expression of BLK has been linked to various complex diseases, including autoimmune disorders, and specific malignancies of B cells, such as lymphomas and leukemias. Due to its significant involvement in B-cell signaling, BLK has emerged as a promising target for drug development, offering the potential for developing novel therapeutics to combat these diseases. Small molecule inhibitors of BLK hold great potential for therapeutic intervention; however, discovering potent and selective inhibitors remains challenging. Within this context, natural compounds hold significant potential as a valuable resource for discovering novel inhibitors of BLK. In the current study, a structure-based virtual screening of the IMPPAT 2 library was employed to identify promising candidates with potential as inhibitors of BLK. The control molecule for this study was the known BLK inhibitor, Dasatinib. After a multi-step filtering process, two molecules (Withanolide I and Mexogenin) demonstrated potential against BLK based on their superior binding affinity, ligand efficiency, and specific interaction. Interaction analysis of these compounds revealed several significant interactions with the active site residues of BLK. Both proposed molecules remained bound to the binding pocket of BLK, as indicated by the molecular dynamics (MD) simulation study. Taken together, these findings provide valuable insights for guiding future research endeavors and translational efforts in developing therapeutics for different complex diseases, such as autoimmune disorders, lymphomas, and leukemias.Communicated by Ramaswamy H. Sarma.

The Evolving Role of Bruton's Tyrosine Kinase Inhibitors in B Cell Lymphomas

Bruton's tyrosine kinase (BTK), a non-receptor tyrosine kinase crucial for B cell development and function, acts downstream of the B cell receptor (BCR) in the BCR pathway. Other kinases involved downstream of the BCR besides BTK such as Syk, Lyn, PI3K, and Mitogen-activated protein (MAP) kinases also play roles in relaying signals from the BCR to provide pro-survival, activation, and proliferation cues. BTK signaling is implicated in various B-cell lymphomas such as mantle cell lymphoma, Waldenström Macroglobulinemia, follicular lymphoma, and diffuse large B cell lymphoma, leading to the development of transformative treatments like ibrutinib, the first-in-class covalent BTK inhibitor, and pirtobrutinib, the first-in-class noncovalent BTK inhibitor. However, kinase-deficient mutations C481F, C481Y, C481R, and L528W in the BTK gene confer resistance to both covalent and non-covalent BTK inhibitors, facilitating B cell survival and lymphomagenesis despite kinase inactivation. Further studies have revealed BTK's non-catalytic scaffolding function, mediating the assembly and activation of proteins including Toll-like receptor 9 (TLR9), vascular cell adhesion protein 1 (VCAM-1), hematopoietic cell kinase (HCK), and integrin-linked kinase (ILK). This non-enzymatic role promotes cell survival and proliferation independently of kinase activity. Understanding BTK's dual roles unveils opportunities for therapeutics targeting its scaffolding function, promising advancements in disrupting lymphomagenesis and refining B cell lymphoma treatments.

In Silico Approach to Molecular Profiling of the Transition from Ovarian Epithelial Cells to Low-Grade Serous Ovarian Tumors for Targeted Therapeutic Insights

This paper aims to elucidate the differentially coexpressed genes, their potential mechanisms, and possible drug targets in low-grade invasive serous ovarian carcinoma (LGSC) in terms of the biologic continuity of normal, borderline, and malignant LGSC. We performed a bioinformatics analysis, integrating datasets generated using the GPL570 platform from different studies from the GEO database to identify changes in this transition, gene expression, drug targets, and their relationships with tumor microenvironmental characteristics. In the transition from ovarian epithelial cells to the serous borderline, the FGFR3 gene in the "Estrogen Response Late" pathway, the ITGB2 gene in the "Cell Adhesion Molecule", the CD74 gene in the "Regulation of Cell Migration", and the IGF1 gene in the "Xenobiotic Metabolism" pathway were upregulated in the transition from borderline to LGSC. The ERBB4 gene in "Proteoglycan in Cancer", the AR gene in "Pathways in Cancer" and "Estrogen Response Early" pathways, were upregulated in the transition from ovarian epithelial cells to LGSC. In addition, SPP1 and ITGB2 genes were correlated with macrophage infiltration in the LGSC group. This research provides a valuable framework for the development of personalized therapeutic approaches in the context of LGSC, with the aim of improving patient outcomes and quality of life. Furthermore, the main goal of the current study is a preliminary study designed to generate in silico inferences, and it is also important to note that subsequent in vitro and in vivo studies will be necessary to confirm the results before considering these results as fully reliable.

The Importance of Tracking "Missing" Metabolites: How and Why?

Technologies currently employed to find and identify drug metabolites in complex biological matrices generally yield results that offer a comprehensive picture of the drug metabolite profile. However, drug metabolites can be missed or are captured only late in the drug development process. This could be due to a variety of factors, such as metabolism that results in partial loss of the molecule, covalent bonding to macromolecules, the drug being metabolized in specific human tissues, or poor ionization in a mass spectrometer. These scenarios often draw a great deal of attention from chemistry, safety assessment, and pharmacology. This review will summarize scenarios of missing metabolites, why they are missing, and associated uncovering strategies from deeper investigations. Uncovering previously missed metabolites can have ramifications in drug development with toxicological and pharmacological consequences, and knowledge of these can help in the design of new drugs.

Orelabrutinib for the treatment of relapsed or refractory marginal zone lymphoma: A phase 2, multicenter, open-label study

Marginal zone lymphoma (MZL) is an indolent type of non-Hodgkin lymphoma that develops through pathological B cell receptor signaling. Orelabrutinib, a new-generation oral small molecule Bruton's tyrosine kinase inhibitor, was evaluated in relapsed/refractory (r/r) MZL patients. Previously treated r/r MZL patients received orelabrutinib 150 mg once daily in a phase 2, multicenter, single-arm study conducted in China. The primary endpoint was overall response rate (ORR) assessed by an Independent Review Committee (IRC) based on the Lugano 2014 classification. Other efficacy, safety, and pharmacokinetic profiles were evaluated as secondary outcome measures. A total of 111 patients were enrolled, of which 90 patients had MZL confirmed by central pathology review, who were mainly with extra-nodal MZL of mucosa-associated lymphoid tissue (MALT, 46.7%) and nodal MZL (35.6%). The majority had late-stage disease, with stage IV accounting for 75.6%. After a median follow-up duration of 24.3 months, the IRC-assessed ORR was 58.9% (95% confidence interval [CI], 48.0-69.2), with rates of complete response and partial response being 11.1% and 47.8%, respectively. The IRC-assessed median duration of response was 34.3 months, and the IRC-assessed median progression-free survival (PFS) was not reached with a 12-month PFS rate of 82.8% (95% CI, 72.6-89.5). The rate of overall survival at 12 months was 91.0% (95% CI, 82.8-95.4). Common all-grade treatment-related adverse events (TRAEs) included anemia (27.9%), neutrophil count decrease (23.4%), white blood cell count decrease (18.0%), platelet count decrease (17.1%), blood present in urine (16.2%), rash (14.4%), and upper respiratory tract infection (10.8%). Thirty-four patients (30.6%) experienced grade 3 or higher TRAEs. Serious TRAEs occurred in 18 patients (16.2%), of which pneumonia (5.4%) was the most common. Seven patients (6.3%) discontinued orelabrutinib due to TRAEs. Orelabrutinib demonstrated high response rates with durable disease remission and was well tolerated in Chinese patients with r/r MZL.

Readministration of high-dose adeno-associated virus gene therapy vectors enabled by ImmTOR nanoparticles combined with B cell-targeted agents

Tolerogenic ImmTOR nanoparticles encapsulating rapamycin have been demonstrated to mitigate immunogenicity of adeno-associated virus (AAV) gene therapy vectors, enhance levels of transgene expression, and enable redosing of AAV at moderate vector doses of 2 to 5E12 vg/kg. However, recent clinical trials have often pushed AAV vector doses 10-fold to 50-fold higher, with serious adverse events observed at the upper range. Here, we assessed combination therapy of ImmTOR with B cell-targeting drugs for the ability to increase the efficiency of redosing at high vector doses. The combination of ImmTOR with a monoclonal antibody against B cell activation factor (aBAFF) exhibited strong synergy leading to more than a 5-fold to 10-fold reduction of splenic mature B cells and plasmablasts while increasing the fraction of pre-/pro-B cells. In addition, this combination dramatically reduced anti-AAV IgM and IgG antibodies, thus enabling four successive AAV administrations at doses up to 5E12 vg/kg and at least two AAV doses at 5E13 vg/kg, with the transgene expression level in the latter case being equal to that observed in control animals receiving a single vector dose of 1E14 vg/kg. Similar synergistic effects were seen with a combination of ImmTOR and a Bruton's tyrosine kinase inhibitor, ibrutinib. These results suggest that ImmTOR could be combined with B cell-targeting agents to enable repeated vector administrations as a potential strategy to avoid toxicities associated with vector doses above 1E14 vg/kg.

In Vitro and In Vivo Effects of Synthesis Novel Phenoxyacetamide Derivatives as Potent Apoptotic Inducer against HepG2 Cells through PARP-1 Inhibition

To discover potential cytotoxic agents, new semi-synthetic phenoxy acetamide derivatives, compound I and compound II, were synthesized, characterized, and screened for their cytotoxic activity against breast cancer (MCF-7) and liver cancer (HepG2) cell lines. The two compounds were more promising against HepG2 than the MCF-7 cell line according to IC50 values. When tested against the HepG2 cell line, compound I, and compound II both had significantly increased cytotoxic activity when compared to the reference medication 5-Fluorouracil (5-FU), with IC50 values of 1.43 M, 5.32 M, and 6.52 M for compound 1, 5-FU and compound II, respectively. Also, compound I displayed a degree of selectivity towards cancer cells compared to normal cells. Compound I significantly enhanced HepG2 total apoptotic cell death by about a 24.51-fold increase. According to cell cycle analysis, compound I induced the arrest of the cell cycle phases G1/S and blocked the progression of the HepG2 cells. Applying the RT-PCR technique achieved a highly significant upregulation in pro-apoptotic genes. The anti-apoptotic gene was significantly downregulated. There was an intrinsic and extrinsic pathway, but the intrinsic pathway was the dominant one. Tumor growth suppression as measured by tumor weight and volume and other hematological, biochemical, and histopathological analyses confirmed the efficacy of compound I as an anticancer agent in vivo examination. Finally, the molecular docking study revealed that compound I was properly docked inside the binding site of PARP-1 protein with stable binding energies and interactive binding modes. Therefore, compound I shows promise as a selective anti-cancer derivative for the treatment of liver cancer after more investigations and clinical studies. This selectivity is a favorable characteristic in the developing cytotoxic agents for cancer treatment, as it indicates a potential for reduced harm to health tissues.

Ibrutinib directly reduces CD8+T cell exhaustion independent of BTK

Introduction

Cytotoxic CD8+ T cell (CTL) exhaustion is a dysfunctional state of T cells triggered by persistent antigen stimulation, with the characteristics of increased inhibitory receptors, impaired cytokine production and a distinct transcriptional profile. Evidence from immune checkpoint blockade therapy supports that reversing T cell exhaustion is a promising strategy in cancer treatment. Ibrutinib, is a potent inhibitor of BTK, which has been approved for the treatment of chronic lymphocytic leukemia. Previous studies have reported improved function of T cells in ibrutinib long-term treated patients but the mechanism remains unclear. We investigated whether ibrutinib directly acts on CD8+ T cells and reinvigorates exhausted CTLs.

Methods

We used an established in vitro CTL exhaustion system to examine whether ibrutinib can directly ameliorate T cell exhaustion. Changes in inhibitory receptors, transcription factors, cytokine production and killing capacity of ibrutinib-treated exhausted CTLs were detected by flow cytometry. RNA-seq was performed to study transcriptional changes in these cells. Btk deficient mice were used to confirm that the effect of ibrutinib was independent of BTK expression.

Results

We found that ibrutinib reduced exhaustion-related features of CTLs in an in vitro CTL exhaustion system. These changes included decreased inhibitory receptor expression, enhanced cytokine production, and downregulation of the transcription factor TOX with upregulation of TCF1. RNA-seq further confirmed that ibrutinib directly reduced the exhaustion-related transcriptional profile of these cells. Importantly, using btk deficient mice we showed the effect of ibrutinib was independent of BTK expression, and therefore mediated by one of its other targets.

Discussion

Our study demonstrates that ibrutinib directly ameliorates CTL exhaustion, and provides evidence for its synergistic use with cancer immunotherapy.

Cardiotoxicity of anti-cancer drugs: cellular mechanisms and clinical implications

Cardio-oncology is an emerging field that seeks to enhance quality of life and longevity of cancer survivors. It is pertinent for clinicians to understand the cellular mechanisms of prescribed therapies, as this contributes to robust understanding of complex treatments and off-target effects, improved communication with patients, and guides long term care with the goal to minimise or prevent cardiovascular complications. Our aim is to review the cellular mechanisms of cardiotoxicity involved in commonly used anti-cancer treatments and identify gaps in literature and strategies to mitigate cardiotoxicity effects and guide future research endeavours.

Fc Epsilon RI-Neuroimmune Interplay in Pruritus Triggered by Particulate Matter in Atopic Dermatitis Patients

Atopic dermatitis (AD) is the most common chronic relapsing neuroinflammatory skin disease that is characterized by a complex and multifactorial pathophysiology. It reflects a profound interplay between genetic and environmental factors, and a recently disclosed neuroimmune dysregulation that drives skin barrier disruption, pruritus, and microbial imbalance. In terms of the key external environmental players that impact AD, air quality and itch severity linkage have been thoroughly researched. The impact of ambient air pollutants including particulate matter (PM) and AD pruritic exacerbation has been recorded despite reductions in air pollution levels in in developed countries. The developing countries have, on the contrary, experienced significant urbanization and industrialization with limited environmental protection standards in the past decades. This unprecedented construction, petrochemical industry utilization, and increment in population counts has been paired with consistent exposure to outdoor PM. This may present a key cause of AD pruritic exacerbation supported by the fact that AD prevalence has intensified globally in the past 50 years, indicating that environmental exposure may act as a trigger that could flare up itch in vulnerable persons. At the molecular level, the impact of PM on severe pruritus in AD could be interpreted by the toxic effects on the complex neuroimmune pathways that govern this disease. AD has been recently viewed as a manifestation of the disruption of both the immune and neurological systems. In light of these facts, this current review aims to introduce the basic concepts of itch sensory circuits in the neuroimmune system. In addition, it describes the impact of PM on the potential neuroimmune pathways in AD pathogenesis with a special focus on the Fc Epsilon RI pathway. Finally, the review proposes potential treatment lines that could be targeted to alleviate pruritus based on immune mediators involved in the Fc Epsilon signaling map.

Extraordinary clinical response to ibrutinib in low-grade ovarian cancer guided by organoid drug testing

Low-grade serous ovarian cancer (LGSOC) typically responds poorly to standard platinum-based chemotherapy and new therapeutic approaches are needed. We describe a remarkable response to targeted therapy in a patient with platinum-resistant, advanced LGSOC who had failed standard-of-care chemotherapy and two surgeries. The patient was in rapid decline and entering hospice care on home intravenous (i.v.) opioid analgesics and a malignant bowel obstruction requiring a G-tube. Genomic analysis of the patient's tumor did not indicate obvious therapeutic options. In contrast, a CLIA-certified drug sensitivity assay of an organoid culture derived from the patient's tumor identified several therapeutic choices, including Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, as well as the EGFR inhibitors afatinib and erlotinib. Following off-label administration of daily ibrutinib as monotherapy, the patient had an exceptional clinical turnaround over the following 65 weeks with normalization of CA-125 levels, resolution of the malignant bowel obstruction, halting of pain medications, and improvement of performance status from ECOG 3 to ECOG 1. After 65 weeks of stable disease, the patient's CA-125 levels began to rise, at which point the patient discontinued ibrutinib and began taking afatinib as monotherapy. The patient's CA-125 levels remained stable for an additional 38 weeks but due to anemia and rising CA-125 levels, the patient switched to erlotinib and is currently being monitored. This case highlights the clinical utility of ex vivo drug testing of patient-derived tumor organoids as a new functional precision medicine approach to identify effective personalized therapies for patients who have failed standard-of-care treatments.

PROTAC'ing oncoproteins: targeted protein degradation for cancer therapy

Molecularly targeted cancer therapies substantially improve patient outcomes, although the durability of their effectiveness can be limited. Resistance to these therapies is often related to adaptive changes in the target oncoprotein which reduce binding affinity. The arsenal of targeted cancer therapies, moreover, lacks coverage of several notorious oncoproteins with challenging features for inhibitor development. Degraders are a relatively new therapeutic modality which deplete the target protein by hijacking the cellular protein destruction machinery. Degraders offer several advantages for cancer therapy including resiliency to acquired mutations in the target protein, enhanced selectivity, lower dosing requirements, and the potential to abrogate oncogenic transcription factors and scaffolding proteins. Herein, we review the development of proteolysis targeting chimeras (PROTACs) for selected cancer therapy targets and their reported biological activities. The medicinal chemistry of PROTAC design has been a challenging area of active research, but the recent advances in the field will usher in an era of rational degrader design.

Rare deleterious mutations in Bruton's tyrosine kinase as biomarkers for ibrutinib-based therapy: an in silico insight

CONTEXT

Squamous cell carcinoma (SCC) is the second most common type of skin cancer caused by malignant keratinocytes. Multiple studies have shown that protein mutations have a significant impact on the development and progression of cancer, including SCC. We attempted to decode the effect of single amino acid mutations in the Bruton's tyrosine kinase (BTK) protein in this study. Molecular dynamic (MD) simulations were performed on selected deleterious mutations of the BTK protein, revealing that the variants adversely affect the protein, indicating that they may contribute to the prognosis of SCC by making the protein unstable. Then, we investigated the interaction between the protein and its mutants with ibrutinib, a drug designed to treat SCC. Even though the mutations have deleterious effects on protein structure, they bind to ibrutinib similarly to their wild type counterpart. This study demonstrates that the effect of detected missense mutations is unfavorable and can result in function loss, which is severe for SCC, but that ibrutinib-based therapy can still be effective on them, and the mutations can be used as biomarkers for Ibrutinib-based treatment.

METHODS

Seven different computational techniques were used to compute the effect of SAVs in accordance with the experimental requirements of this study. To understand the differences in protein and mutant dynamics, MD simulation and trajectory analysis, including RMSD, RMSF, PCA, and contact analysis, were performed. The free binding energy and its decomposition for each protein-drug complex were determined using docking, MM-GBSA, MM-PBSA, and interaction analysis (wild and mutants).

A Phase 2 Trial of Ibrutinib and Nivolumab in Patients with Relapsed or Refractory Classical Hodgkin's Lymphoma

BACKGROUND

Relapsed or refractory classical Hodgkin lymphoma (cHL) remains a difficult treatment challenge. Although checkpoint inhibitors (CPI) have provided clinical benefit for these patients, responses are generally not durable, and progression eventually occurs. Discovering combination therapies which maximize the immune response of CPI therapy may overcome this limitation. We hypothesized that adding ibrutinib to nivolumab will lead to deeper and more durable responses in cHL by promoting a more favorable immune microenvironment leading to enhanced T-cell-mediated anti-lymphoma responses.

METHODS

We conducted a single arm, phase II clinical trial testing the efficacy of nivolumab in combination with ibrutinib in patients ≥18 years of age with histologically confirmed cHL who had received at least one prior line of therapy. Prior treatment with CPIs was allowed. Ibrutinib was administered at 560 mg daily until progression in combination with nivolumab 3 mg/kg IV every 3 weeks for up to 16 cycles. The primary objective was complete response rate (CRR) assessed per Lugano criteria. Secondary objectives included overall response rate (ORR), safety, progression free survival (PFS), and duration of response (DoR).

RESULTS

A total of 17 patients from two academic centers were enrolled. The median age of all patients was 40 (range 20-84). The median number of prior lines of treatment was five (range 1-8), including 10 patients (58.8%) who had progressed on prior nivolumab therapy. Most treatment related events were mild (

CONCLUSIONS

Combined nivolumab and ibrutinib led to a CRR of 29.4% in R/R cHL. Although this study did not meet its primary efficacy endpoint of a CRR of 50%, likely due to enrollment of heavily pretreated patients including over half of who had progressed on prior nivolumab treatment, responses that were achieved with combination ibrutinib and nivolumab therapy tended to be durable even in the case of prior progression on nivolumab therapy. Larger studies investigating the efficacy of dual BTK inhibitor/immune checkpoint blockade, particularly in patients who had previously progressed on checkpoint blockade therapy, are warranted.

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Key Words

• Hodgkin’s lymphoma
• ibrutinib
• nivolumab

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Grants

• P30 CA016058 NCI NIH HHS

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Affiliation(s)

Walter Hanel Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Polina Shindiapina Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
David A. Bond Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Yazeed Sawalha Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Narendranath Epperla Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Timothy Voorhees Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Rina Li Welkie Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Ying Huang Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Gregory K. Behbehani Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Xiaoli Zhang Center for Biostatistics, Department of Biomedical Informatics, The Ohio State University, Columbus, OH 43210, USA
Eric McLaughlin Center for Biostatistics, Department of Biomedical Informatics, The Ohio State University, Columbus, OH 43210, USA
Wing K. Chan Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Jonathan E. Brammer Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Samantha Jaglowski Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
John C. Reneau Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Beth A. Christian Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Basem M. William Blood and Marrow Transplant and Cell Therapy Program, OhioHealth, 500 Thomas Ln #A3, Columbus, OH 43214, USA
Jonathon B. Cohen Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, 1365 Clifton Road NE, B4013, Atlanta, GA 30322, USA
Robert A. Baiocchi Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Kami Maddocks Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA
Kristie A. Blum Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, 1365 Clifton Road NE, B4013, Atlanta, GA 30322, USA
Lapo Alinari Division of Hematology, Department of Medicine, The Ohio State University, 460 W 10th Ave., Columbus, OH 43210, USA

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Targeting B Cells and Microglia in Multiple Sclerosis With Bruton Tyrosine Kinase Inhibitors: A Review

Importance

Currently, disease-modifying therapies for multiple sclerosis (MS) use 4 mechanisms of action: immune modulation, suppressing immune cell proliferation, inhibiting immune cell migration, or cellular depletion. Over the last decades, the repertoire substantially increased because of the conceptual progress that not only T cells but also B cells play an important pathogenic role in MS, fostered by the empirical success of B cell-depleting antibodies against the surface molecule CD20. Notwithstanding this advance, a continuous absence of B cells may harbor safety risks, such as a decline in the endogenous production of immunoglobulins. Accordingly, novel B cell-directed MS therapies are in development, such as inhibitors targeting Bruton tyrosine kinase (BTK).

Observations

BTK is centrally involved in the B cell receptor-mediated activation of B cells, one key requirement in the development of autoreactive B cells, but also in the activation of myeloid cells, such as macrophages and microglia. Various compounds in development differ in their binding mode, selectivity and specificity, relative inhibitory concentration, and potential to enter the central nervous system. The latter may be important in assessing whether BTK inhibition is a promising strategy to control inflammatory circuits within the brain, the key process that is assumed to drive MS progression. Accordingly, clinical trials using BTK inhibitors are currently conducted in patients with relapsing-remitting MS as well as progressive MS, so far generating encouraging data regarding efficacy and safety.

Conclusions and Relevance

While the novel approach of targeting BTK is highly promising, several questions remain unanswered, such as the long-term effects of using BTK inhibitors in the treatment of inflammatory CNS disease. Potential changes in circulating antibody levels should be evaluated and compared with B cell depletion. Also important is the potential of BTK inhibitors to enter the CNS, which depends on the given compound. Remaining questions involve where BTK inhibitors fit in the landscape of MS therapeutics. A comparative analysis of their distinct properties is necessary to identify which inhibitors may be used in relapsing vs progressive forms of MS as well as to clarify which agent may be most suitable for sequential use after anti-CD20 treatment.

Zanubrutinib Versus Ibrutinib in Relapsed/Refractory Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma: Interim Analysis of a Randomized Phase III Trial

PURPOSE

Zanubrutinib is a potent, irreversible next-generation Bruton tyrosine kinase (BTK) inhibitor designed to maximize BTK occupancy and minimize off-target kinase inhibition. We hypothesized that complete/sustained BTK occupancy may improve efficacy outcomes and increased BTK specificity may minimize off-target inhibition-related toxicities.

PATIENTS AND METHODS

ALPINE (ClinicalTrials.gov identifier: NCT03734016) is a global, randomized, open-label phase III study of zanubrutinib versus ibrutinib in patients with relapsed/refractory chronic lymphocytic leukemia. The primary end point was investigator-assessed overall response rate (ORR). The preplanned interim analysis was scheduled approximately 12 months after the first 415 patients were enrolled.

RESULTS

Between November 1, 2018, and December 14, 2020, 652 patients were enrolled. We present the interim analysis of the first 415 enrolled patients randomly assigned to receive zanubrutinib (n = 207) or ibrutinib (n = 208). At 15 months of median follow-up, ORR (partial or complete response) was significantly higher with zanubrutinib (78.3%; 95% CI, 72.0 to 83.7) versus ibrutinib (62.5%; 95% CI, 55.5 to 69.1; two-sided P < .001). ORR was higher with zanubrutinib versus ibrutinib in subgroups with del(17p)/TP53 mutations (80.5% v 50.0%) and del(11q) (83.6% v 69.1%); 12-month progression-free survival in all patients was higher with zanubrutinib (94.9%) versus ibrutinib (84.0%; hazard ratio, 0.40; 95% CI, 0.23 to 0.69). Atrial fibrillation rate was significantly lower with zanubrutinib versus ibrutinib (2.5% v 10.1%; two-sided P = .001). Rates of cardiac events, major hemorrhages, and adverse events leading to treatment discontinuation/death were lower with zanubrutinib.

CONCLUSION

Zanubrutinib had a significantly higher ORR, lower atrial fibrillation rate, and improved progression-free survival and overall cardiac safety profile versus ibrutinib. These data support improved efficacy/safety outcomes with selective BTK inhibition.

Zanubrutinib or Ibrutinib in Relapsed or Refractory Chronic Lymphocytic Leukemia

BACKGROUND

In a multinational, phase 3, head-to-head trial, ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, was compared with zanubrutinib, a BTK inhibitor with greater specificity, as treatment for relapsed or refractory chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). In prespecified interim analyses, zanubrutinib was superior to ibrutinib with respect to overall response (the primary end point). Data from the final analysis of progression-free survival are now available.

METHODS

We randomly assigned, in a 1:1 ratio, patients with relapsed or refractory CLL or SLL who had received at least one previous course of therapy to receive zanubrutinib or ibrutinib until the occurrence of disease progression or unacceptable toxic effects. In this final analysis, progression-free survival (a key secondary end point) was assessed with the use of a hierarchical testing strategy to determine whether zanubrutinib was noninferior to ibrutinib. If noninferiority was established, the superiority of zanubrutinib was assessed and claimed if the two-sided P value was less than 0.05.

RESULTS

At a median follow-up of 29.6 months, zanubrutinib was found to be superior to ibrutinib with respect to progression-free survival among 652 patients (hazard ratio for disease progression or death, 0.65; 95% confidence interval, [CI], 0.49 to 0.86; P = 0.002), as assessed by the investigators; the results were similar to those as assessed by an independent-review committee. At 24 months, the investigator-assessed rates of progression-free survival were 78.4% in the zanubrutinib group and 65.9% in the ibrutinib group. Among patients with a 17p deletion, a TP53 mutation, or both, those who received zanubrutinib had longer progression-free survival than those who received ibrutinib (hazard ratio for disease progression or death, 0.53; 95% CI, 0.31 to 0.88); progression-free survival across other major subgroups consistently favored zanubrutinib. The percentage of patients with an overall response was higher in the zanubrutinib group than in the ibrutinib group. The safety profile of zanubrutinib was better than that of ibrutinib, with fewer adverse events leading to treatment discontinuation and fewer cardiac events, including fewer cardiac events leading to treatment discontinuation or death.

CONCLUSIONS

In patients with relapsed or refractory CLL or SLL, progression-free survival was significantly longer among patients who received zanubrutinib than among those who received ibrutinib, and zanubrutinib was associated with fewer cardiac adverse events. (Funded by BeiGene; ALPINE ClinicalTrials.gov number, NCT03734016.).

Targeting Ibrutinib to Tumor-Infiltrating T Cells with a Sialic Acid Conjugate-Modified Phospholipid Complex for Improved Tumor Immunotherapy

Immune checkpoint blockade (ICB) treatment for the clinical therapy of numerous malignancies has attracted widespread attention in recent years. Despite being a promising treatment option, developing complementary strategies to enhance the proportion of patients benefiting from ICB therapy remains a formidable challenge because of the complexity of the tumor microenvironment. Ibrutinib (IBR), a covalent inhibitor of Bruton's tyrosine kinase (BTK), has been approved as a clinical therapy for numerous B-cell malignancies. IBR also irreversibly inhibits interleukin-2 inducible T cell kinase (ITK), an essential enzyme in Th2-polarized T cells that participates in tumor immunosuppression. Ablation of ITK by IBR can elicit Th1-dominant antitumor immune responses and potentially enhance the efficacy of ICB therapy in solid tumors. However, its poor solubility and rapid clearance in vivo restrict T cell targetability and tumor accumulation by IBR. A sialic acid derivative-modified nanocomplex (SA-GA-OCT@PC) has been reported to improve the efficacy of IBR-mediated combination immunotherapy in solid tumors. In vitro and in vivo experiments showed that SA-GA-OCT@PC effectively accumulated in tumor-infiltrating T cells mediated by Siglec-E and induced Th1-dominant antitumor immune responses. SA-GA-OCT@PC-mediated combination therapy with PD-L1 blockade agents dramatically suppressed tumor growth and inhibited tumor relapse in B16F10 melanoma mouse models. Overall, the combination of the SA-modified nanocomplex platform and PD-L1 blockade offers a treatment opportunity for IBR in solid tumors, providing novel insights for tumor immunotherapy.

Preparation and Optimization of Ibrutinib-Loaded Nanoliposomes Using Response Surface Methodology

The main aim of this study was to optimize the formulation and process variables for the preparation of ibrutinib nanoliposomes and to evaluate the stability of nanoliposomes. The influence of four formulations and process parameters, namely, the phosphatidylcholine-to-cholesterol ratio (A), conc. of ibrutinib (B), sonication time (C), and stirring time (D) on the drug encapsulation efficiency (Y₁) and particle size (Y₂) of ibrutinib nanoliposomes were investigated by using response surface methodology. Reverse-phase evaporation was used to prepare ibrutinib nanoliposomes. Twenty-nine trial experiments were performed as per the design and the response parameters were noted. Multiple linear regression analysis was used to assess each response parameter. The effect of each factor on the response parameters was depicted using perturbation, response surface, and contour plots. A numerical optimization technique was used to estimate the optimum process parameters to obtain the desired responses. Ibrutinib nanoliposomes prepared under optimal conditions were evaluated for stability at a different temperature, pH, and sonication time. It is evident from the results that the phosphatidylcholine-to-cholesterol ratio (A) was the major factor influencing the encapsulation efficiency. All the factors were found to have noteworthy influences on particle size. A statistical evaluation provided the information about the individual and interactive effects of independent factors on the response parameters in order to obtain optimum experimental conditions that lead to preparing nanoliposomes with improved characteristics. The optimum level of the independent variables was phosphatidylcholine:cholesterol (6.76:1), ibrutinib concentration (2 mg/mL), sonication time (15.13 min), and stirring time (45 min). At optimal conditions, Y₁ and Y₂ were found to be 90.76 ± 1.56% and 208.24 ± 3.16 nm, respectively. The ibrutinib nanoliposomes were found to be stable both in simulated gastric and intestinal fluids at 37 °C for 6 h. At elevated conditions of temperature and pH, the prepared nanoliposomes were found to be unstable. Sonication for shorter periods resulted in decreased particle size, whereas longer periods can be helpful for ultrasound-assisted drug delivery. The closeness between the obtained results and predicted results indicates the reliability of the optimization technique for the preparation of ibrutinib nanoliposomes.

Risk of HBV reactivation in relapsed or refractory diffuse large B-cell lymphoma patients receiving Bruton tyrosine kinase inhibitors therapy

Background

Bruton tyrosine kinase inhibitors (BTKis) interrupt B-cell receptor signaling and thereby could potentially reactivate hepatitis B virus (HBV). However, data about the risk for HBV reactivation (HBVr) of BTKis in relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL) patients are sparse.

Methods

A total of 55 R/R DLBCL patients receiving BTKis therapy in the Tongji Hospital of Tongji University were enrolled. Patient clinical characteristics, treatment outcomes and details of HBVr were collected and analyzed, aiming to demonstrate the risk of HBVr in R/R DLBCL patients post BTKis therapy and the efficacy of BTKis in HBV-associated R/R DLBCL patients.

Results

Of 55 R/R DLBCL patients treated with ibrutinib (N=38) and zanubrutinib (N=17), 4 were with chronic HBV infection (HBsAg positive), 26 with resolved HBV infection (HBsAg negative and HBcAb positive) and 25 without HBV infection (HBsAg negative and HBcAb negative). In resolved HBV infection group, 2 patients developed HBVr after the use of ibrutinib and zanubrutinib respectively. Neither of them developed HBV-related hepatitis. Our finding showed that the incidence of HBVr in resolved HBV infection group was 7.69% (95% CI, 0.9-25.1%). In this study, Overall response rate (ORR) was 70.9%. 1-year overall survival (OS) rate was 80.0%. Median progression-free survival (PFS) was 4 months (95% CI, 3-5 months). In addition, HBV infection was not associated with response rates or survival among R/R DLBCL patients post BTKis treatments.

Conclusion

Our study suggested that HBV infection do not affect the efficacy of BTKis’ treatment. However, R/R DLBCL patients with resolved HBV infection are at a moderate risk of developing HBVr throughout BTKis treatment. Patients should be screened for HBVr during BTKis therapy.

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

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

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.

BTK inhibitor selection for chronic lymphocytic leukemia: which drug for which patient?

INTRODUCTION

The development of BTK inhibitors has revolutionized the management of CLL. Currently, there are 3 BTK inhibitors available to treat CLL: ibrutinib, acalabrutinib, and zanubrutinib (the latter not yet approved for this disease but included in the NCCN guidelines). In this review, we will elucidate our approach to the selection of BTK inhibitor and provide insight into the future of BTK directed therapy.

AREAS COVERED

This review utilizes data from published prospective trials, specifically RESONATE, RESONATE-2, ELEVATE-TN, ASCEND, ELEVATE-RR, and the ongoing FLAIR, SEQUOIA and ALPINE trials.

EXPERT OPINION

The choice of BTK inhibitor is guided by the setting (frontline vs relapsed) in conjunction with patient disease characteristics and comorbidities. In this review, we will elucidate our approach to the selection of BTK inhibitor and provide insight into the future of BTK directed therapy.

DTI-HETA: prediction of drug-target interactions based on GCN and GAT on heterogeneous graph

Drug-target interaction (DTI) prediction plays an important role in drug repositioning, drug discovery and drug design. However, due to the large size of the chemical and genomic spaces and the complex interactions between drugs and targets, experimental identification of DTIs is costly and time-consuming. In recent years, the emerging graph neural network (GNN) has been applied to DTI prediction because DTIs can be represented effectively using graphs. However, some of these methods are only based on homogeneous graphs, and some consist of two decoupled steps that cannot be trained jointly. To further explore GNN-based DTI prediction by integrating heterogeneous graph information, this study regards DTI prediction as a link prediction problem and proposes an end-to-end model based on HETerogeneous graph with Attention mechanism (DTI-HETA). In this model, a heterogeneous graph is first constructed based on the drug-drug and target-target similarity matrices and the DTI matrix. Then, the graph convolutional neural network is utilized to obtain the embedded representation of the drugs and targets. To highlight the contribution of different neighborhood nodes to the central node in aggregating the graph convolution information, a graph attention mechanism is introduced into the node embedding process. Afterward, an inner product decoder is applied to predict DTIs. To evaluate the performance of DTI-HETA, experiments are conducted on two datasets. The experimental results show that our model is superior to the state-of-the-art methods. Also, the identification of novel DTIs indicates that DTI-HETA can serve as a powerful tool for integrating heterogeneous graph information to predict DTIs.

Determinants of Atrial Fibrillation Development among Patients undergoing Ibrutinib Therapy

Objective: Within the last decade, the use of ibrutinib, a first-generation, non-selective, irreversible Burton's tyrosine kinase inhibitor for the treatment of hematological malignancies has proven highly effective in improving patient outcomes.Background: Ibrutinib has been associated with an increase in atrial fibrillation (AF). The predisposing factors are thought to be pre-existing cardiovascular risk factors, but these have not been directly evaluated.Methods: We conducted a nested case-control study, recruiting consecutive ibrutinib treated subjects to evaluate cardiovascular risk factors associated with the development of AF in patients diagnosed with hematological B-cell malignancies.Results: Of the 189 patients treated with ibrutinib and without AF at baseline, 54 (29%) developed AF. Cardiovascular risk factors associated with AF development were, older age, prior hypertension (HTN), history of heart failure (HF) and congenital heart disease. A patient with HF at baseline had a 1, 2, 6, and 12 month cumulative hazard of AF of 40%, 48%, 64%, and 71%, respectively. Patients with prior HTN without HF at baseline had a 1, 2, 6, and 12 month cumulative hazard of AF of 5%, 10%, 23%, and 31%, respectively while on ibrutinib therapy.Conclusions: The relationship between ibrutinib, cardiovascular comorbidities, and AF is through pre-existing cardiovascular disease. An individualized, multidisciplinary approach involving cardiologists should be considered when initiating ibrutinib, particularly when there is a history of HTN, HF or congenital heart disease. In such patients, there should be close cardiovascular monitoring and prompt intervention when AF develops to improve patient outcomes.

Drug repurposing for rheumatoid arthritis: Identification of new drug candidates via bioinformatics and text mining analysis

Rheumatoid arthritis (RA) is an autoimmune disease that results in the destruction of tissue by attacks on the patient by his or her own immune system. Current treatment strategies are not sufficient to overcome RA. In the present study, various transcriptomic data from synovial fluids, synovial fluid-derived macrophages, and blood samples from patients with RA were analysed using bioinformatics approaches to identify tissue-specific repurposing drug candidates for RA. Differentially expressed genes (DEGs) were identified by integrating datasets for each tissue and comparing diseased to healthy samples. Tissue-specific protein-protein interaction (PPI) networks were generated and topologically prominent proteins were selected. Transcription-regulating biomolecules for each tissue type were determined from protein-DNA interaction data. Common DEGs and reporter biomolecules were used to identify drug candidates for repurposing using the hypergeometric test. As a result of bioinformatic analyses, 19 drugs were identified as repurposing candidates for RA, and text mining analyses supported our findings. We hypothesize that the FDA-approved drugs momelotinib, ibrutinib, and sodium butyrate may be promising candidates for RA. In addition, CHEMBL306380, Compound 19a (CHEMBL3116050), ME-344, XL-019, TG100801, JNJ-26483327, and NV-128 were identified as novel repurposing candidates for the treatment of RA. Preclinical and further validation of these drugs may provide new treatment options for RA.

A Review of HER4 (ErbB4) Kinase, Its Impact on Cancer, and Its Inhibitors

HER4 is a receptor tyrosine kinase that is required for the evolution of normal body systems such as cardiovascular, nervous, and endocrine systems, especially the mammary glands. It is activated through ligand binding and activates MAPKs and PI3K/AKT pathways. HER4 is commonly expressed in many human tissues, both adult and fetal. It is important to understand the role of HER4 in the treatment of many disorders. Many studies were also conducted on the role of HER4 in tumors and its tumor suppressor function. Mostly, overexpression of HER4 kinase results in cancer development. In the present article, we reviewed the structure, location, ligands, physiological functions of HER4, and its relationship to different cancer types. HER4 inhibitors reported mainly from 2016 to the present were reviewed as well.

Clinical Trials of the BTK Inhibitors Ibrutinib and Acalabrutinib in Human Diseases Beyond B Cell Malignancies

The BTK inhibitors ibrutinib and acalabrutinib are FDA-approved drugs for the treatment of B cell malignances. Both drugs have demonstrated clinical efficacy and safety profiles superior to chemoimmunotherapy regimens in patients with chronic lymphocytic leukemia. Mounting preclinical and clinical evidence indicates that both ibrutinib and acalabrutinib are versatile and have direct effects on many immune cell subsets as well as other cell types beyond B cells. The versatility and immunomodulatory effects of both drugs have been exploited to expand their therapeutic potential in a wide variety of human diseases. Over 470 clinical trials are currently registered at ClinicalTrials.gov to test the efficacy of ibrutinib or acalabrutinib not only in almost every type of B cell malignancies, but also in hematological malignancies of myeloid cells and T cells, solid tumors, chronic graft versus host disease (cGHVD), autoimmune diseases, allergy and COVID-19 (http:www.clinicaltrials.gov). In this review, we present brief discussions of the clinical trials and relevant key preclinical evidence of ibrutinib and acalabrutinib as monotherapies or as part of combination therapies for the treatment of human diseases beyond B cell malignancies. Adding to the proven efficacy of ibrutinib for cGVHD, preliminary results of clinical trials have shown promising efficacy of ibrutinib or acalabrutinib for certain T cell malignancies, allergies and severe COVID-19. However, both BTK inhibitors have no or limited efficacy for refractory or recurrent solid tumors. These clinical data together with additional pending results from ongoing trials will provide valuable information to guide the design and improvement of future trials, including optimization of combination regimens and dosing sequences as well as better patient stratification and more efficient delivery strategies. Such information will further advance the precise implementation of BTK inhibitors into the clinical toolbox for the treatment of different human diseases.

Reactivities of the Front Pocket N-Terminal Cap Cysteines in Human Kinases

The front pocket (FP) N-terminal cap (Ncap) cysteine is the most popular site of covalent modification in kinases. A long-standing hypothesis associates the Ncap position with cysteine hyper-reactivity; however, traditional computational predictions suggest that the FP Ncap cysteines are predominantly unreactive. Here we applied the state-of-the-art continuous constant pH molecular dynamics (CpHMD) to test the Ncap hypothesis. Simulations found that the Ncap cysteines of BTK/BMX/TEC/ITK/TXK, JAK3, and MKK7 are reactive to varying degrees; however, those of BLK and EGFR/ERBB2/ERBB4 possessing a Ncap+3 aspartate are unreactive. Analysis suggested that hydrogen bonding and electrostatic interactions drive the reactivity, and their absence renders the Ncap cysteine unreactive. To further test the Ncap hypothesis, we examined the FP Ncap+2 cysteines in JNK1/JNK2/JNK3 and CASK. Our work offers a systematic understanding of the cysteine structure-reactivity relationship and illustrates the use of CpHMD to differentiate cysteines toward the design of targeted covalent inhibitors with reduced chemical reactivities.

Clinical pharmacology and PK/PD translation of the second-generation Bruton's tyrosine kinase inhibitor, zanubrutinib

Introduction: Bruton's tyrosine kinase (BTK) inhibitors have revolutionized the treatment of B-cell lymphomas. Zanubrutinib was designed to achieve improved therapeutic concentrations and minimize off-target activities putatively accounting, in part, for the adverse effects seen with other BTK inhibitors.Areas covered: This drug profile covers zanubrutinib clinical pharmacology and the translation of pharmacokinetics (PK) and pharmacodynamics (PD) to clinical efficacy and safety profiles, by highlighting key differences between zanubrutinib and other BTK inhibitors. We discuss PK, sustained BTK occupancy, and potential factors affecting PK of zanubrutinib, including food effects, hepatic impairment, and drug-drug interactions. These data, along with exposure-response analyses, were used to support the recommended dose of 320 mg, either once daily or as 160 mg twice daily. Translation of PK/PD attributes into clinical effects was demonstrated in a randomized, phase 3 head-to-head study comparing it with ibrutinib in patients with Waldenström macroglobulinemia.Expert opinion: Among the approved BTK inhibitors, zanubrutinib is less prone to PK modulation by intrinsic and extrinsic factors, leading to more consistent, sustained therapeutic exposures and improved dosing convenience. Zanubrutinib PK/PD has translated into durable responses and improved safety, representing an important new treatment option for patients who benefit from BTK therapy.

Multifaceted Immunomodulatory Effects of the BTK Inhibitors Ibrutinib and Acalabrutinib on Different Immune Cell Subsets - Beyond B Lymphocytes

The clinical success of the two BTK inhibitors, ibrutinib and acalabrutinib, represents a major breakthrough in the treatment of chronic lymphocytic leukemia (CLL) and has also revolutionized the treatment options for other B cell malignancies. Increasing evidence indicates that in addition to their direct effects on B lymphocytes, both BTK inhibitors also directly impact the homeostasis, phenotype and function of many other cell subsets of the immune system, which contribute to their high efficacy as well as adverse effects observed in CLL patients. In this review, we attempt to provide an overview on the overlapping and differential effects of ibrutinib and acalabrutinib on specific receptor signaling pathways in different immune cell subsets other than B cells, including T cells, NK cells, monocytes, macrophages, granulocytes, myeloid-derived suppressor cells, dendritic cells, osteoclasts, mast cells and platelets. The shared and distinct effects of ibrutinib versus acalabrutinib are mediated through BTK-dependent and BTK-independent mechanisms, respectively. Such immunomodulatory effects of the two drugs have fueled myriad explorations of their repurposing opportunities for the treatment of a wide variety of other human diseases involving immune dysregulation.

Resistance Mutations to BTK Inhibitors Originate From the NF-κB but Not From the PI3K-RAS-MAPK Arm of the B Cell Receptor Signaling Pathway

Since the first clinical report in 2013, inhibitors of the intracellular kinase BTK (BTKi) have profoundly altered the treatment paradigm of B cell malignancies, replacing chemotherapy with targeted agents in patients with chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), and Waldenström's macroglobulinemia. There are over 20 BTKi, both irreversible and reversible, in clinical development. While loss-of-function (LoF) mutations in the BTK gene cause the immunodeficiency X-linked agammaglobulinemia, neither inherited, nor somatic BTK driver mutations are known. Instead, BTKi-sensitive malignancies are addicted to BTK. BTK is activated by upstream surface receptors, especially the B cell receptor (BCR) but also by chemokine receptors, and adhesion molecules regulating B cell homing. Consequently, BTKi therapy abrogates BCR-driven proliferation and the tissue homing capacity of the malignant cells, which are being redistributed into peripheral blood. BTKi resistance can develop over time, especially in MCL and high-risk CLL patients. Frequently, resistance mutations affect the BTKi binding-site, cysteine 481, thereby reducing drug binding. Less common are gain-of-function (GoF) mutations in downstream signaling components, including phospholipase Cγ2 (PLCγ2). In a subset of patients, mechanisms outside of the BCR pathway, related e.g. to resistance to apoptosis were described. BCR signaling depends on many proteins including SYK, BTK, PI3K; still based on the resistance pattern, BTKi therapy only selects GoF alterations in the NF-κB arm, whereas an inhibitor of the p110δ subunit of PI3K instead selects resistance mutations in the RAS-MAP kinase pathway. BTK and PLCγ2 resistance mutations highlight BTK's non-redundant role in BCR-mediated NF-κB activation. Of note, mutations affecting BTK tend to generate clone sizes larger than alterations in PLCγ2. This infers that BTK signaling may go beyond the PLCγ2-regulated NF-κB and NFAT arms. Collectively, when comparing the primary and acquired mutation spectrum in BTKi-sensitive malignancies with the phenotype of the corresponding germline alterations, we find that certain observations do not readily fit with the existing models of BCR signaling.

Novel mouse model resistant to irreversible BTK inhibitors: a tool identifying new therapeutic targets and side effects

Pharmacological inhibitors of Bruton tyrosine kinase (BTK) have revolutionized treatment of B-lymphocyte malignancies and show great promise for dampening autoimmunity. The predominant BTK inhibitors tether irreversibly by covalently binding to cysteine 481 in the BTK catalytic domain. Substitution of cysteine 481 for serine (C481S) is the most common mechanism for acquired drug resistance. We generated a novel C481S knock-in mouse model and, using a battery of tests, no overt B-lymphocyte phenotype was found. B lymphocytes from C481S animals were resistant to irreversible, but sensitive to reversible, BTK inhibitors. In contrast, irreversible inhibitors equally impaired T-lymphocyte activation in mice, mimicking the effect of treatment in patients. This demonstrates that T-lymphocyte blockage is independent of BTK. We suggest that the C481S knock-in mouse can serve as a useful tool for the study of BTK-independent effects of irreversible inhibitors, allowing for the identification of novel therapeutic targets and pinpointing potential side effects.

Myeloid-derived suppressor cell subtypes differentially influence T-cell function, T-helper subset differentiation, and clinical course in CLL

Cancer pathogenesis involves the interplay of tumor- and microenvironment-derived stimuli. Here we focused on the influence of an immunomodulatory cell type, myeloid-derived suppressor cells (MDSCs), and their lineage-related subtypes on autologous T lymphocytes. Although MDSCs as a group correlated with an immunosuppressive Th repertoire and worse clinical course, MDSC subtypes (polymorphonuclear, PMN-MDSC, and monocytic, M-MDSCs) were often functionally discordant. In vivo, PMN-MDSCs existed in higher numbers, correlated with different Th-subsets, and more strongly associated with poor clinical course than M-MDSCs. In vitro, PMN-MDSCs were more efficient at blocking T-cell growth and promoted Th17 differentiation. Conversely, in vitro M-MDSCs varied in their ability to suppress T-cell proliferation, due to the action of TNFα, and promoted a more immunostimulatory Th compartment. Ibrutinib therapy impacted MDSCs differentially as well, since after initiating therapy, PMN-MDSC numbers progressively declined, whereas M-MDSC numbers were unaffected, leading to a set of less immunosuppressive Th cells. Consistent with this, clinical improvement based on decreasing CLL-cell numbers correlated with the decrease in PMN-MDSCs. Collectively, the data support a balance between PMN-MDSC and M-MDSC numbers and function influencing CLL disease course.

Ibrutinib combinations in CLL therapy: scientific rationale and clinical results

Ibrutinib has revolutionized the treatment of chronic lymphocytic leukemia (CLL). This drug irreversibly inhibits Bruton tyrosine kinase (BTK) by covalently binding to the C481 residue in the BTK kinase domain. BTK is a pivotal protein for B cell receptor signaling and tissue homing of CLL cells. Preclinical investigations have established the importance of the B cell receptor pathway in the maintenance and survival of normal and malignant B cells, underscoring the importance of targeting this axis for CLL. Clinical trials demonstrated overall and progression-free survival benefit with ibrutinib in multiple CLL subgroups, including patients with relapsed or refractory disease, patients with 17p deletion, elderly patients, and treatment-naïve patients. Consequently, ibrutinib was approved by the US Food and Drug Administration for newly diagnosed and relapsed disease. Ibrutinib has transformed the treatment of CLL; however, several limitations have been identified, including low complete remission rates, development of resistance, and uncommon substantial toxicities. Further, ibrutinib must be used until disease progression, which imposes a financial burden on patients and society. These limitations were the impetus for the development of ibrutinib combinations. Four strategies have been tested in recent years: combinations of ibrutinib with immunotherapy, chemoimmunotherapy, cell therapy, and other targeted therapy. Here, we review the scientific rationale for and clinical outcome of each strategy. Among these strategies, ibrutinib with targeted agent venetoclax results in high complete response rates and, importantly, high rates of undetectable minimal residual disease. Although we concentrate here on ibrutinib, similar combinations are expected or ongoing with acalabrutinib, tirabrutinib, and zanubrutinib, second-generation BTK inhibitors. Future investigations will focus on the feasibility of discontinuing ibrutinib combinations after a defined time; the therapeutic benefit of adding a third agent to ibrutinib-containing combinations; and profiling of resistant clones that develop after combination treatment. A new standard of care for CLL is expected to emerge from these investigations.

Phase I/II study of tirabrutinib, a second-generation Bruton's tyrosine kinase inhibitor, in relapsed/refractory primary central nervous system lymphoma

Background

The safety, tolerability, efficacy, and pharmacokinetics of tirabrutinib, a second-generation, highly selective oral Bruton’s tyrosine kinase inhibitor, were evaluated for relapsed/refractory primary central nervous system lymphoma (PCNSL).

Methods

Patients with relapsed/refractory PCNSL, Karnofsky performance status ≥70, and normal end-organ function received tirabrutinib 320 and 480 mg once daily (q.d.) in phase I to evaluate dose-limiting toxicity (DLT) within 28 days using a 3 + 3 dose escalation design and with 480 mg q.d. under fasted conditions in phase II.

Results

Forty-four patients were enrolled; 20, 7, and 17 received tirabrutinib at 320, 480, and 480 mg under fasted conditions, respectively. No DLTs were observed, and the maximum tolerated dose was not reached at 480 mg. Common grade ≥3 adverse events (AEs) were neutropenia (9.1%), lymphopenia, leukopenia, and erythema multiforme (6.8% each). One patient with 480 mg q.d. had grade 5 AEs (pneumocystis jirovecii pneumonia and interstitial lung disease). Independent review committee assessed overall response rate (ORR) at 64%: 60% with 5 complete responses (CR)/unconfirmed complete responses (CRu) at 320 mg, 100% with 4 CR/CRu at 480 mg, and 53% with 6 CR/CRu at 480 mg under fasted conditions. Median progression-free survival was 2.9 months: 2.1, 11.1, and 5.8 months at 320, 480, and 480 mg under fasted conditions, respectively. Median overall survival was not reached. ORR was similar among patients harboring CARD11, MYD88, and CD79B mutations, and corresponding wild types.

Conclusion

These data indicate favorable efficacy of tirabrutinib in patients with relapsed/refractory PCNSL.

Trial registration

JapicCTI-173646.

Ibrutinib Has Time-dependent On- and Off-target Effects on Plasma Biomarkers and Immune Cells in Chronic Lymphocytic Leukemia

Supplemental Digital Content is available in the text.

Ibrutinib is a covalently binding inhibitor of the B-cell receptor signaling-mediator Bruton’s tyrosine kinase (BTK) with great efficacy in chronic lymphocytic leukemia (CLL). Common side effects like atrial fibrillation (AF), bleeding and infections might be caused by ibrutinib’s inhibition of other kinases in non-B cells. Five-year follow-up of plasma biomarkers by proximity extension assay and immune cell numbers by flow cytometry during ibrutinib treatment revealed that 86 of the 265 investigated plasma biomarkers significantly changed during treatment, 74 of which decreased. Among the 12 markers that increased, 6 are associated with cardiovascular diseases and therefore potentially involved in ibrutinib-induced AF. Comparison between healthy donors and X-linked agammaglobulinemia (XLA) patients, who have nonfunctional BTK and essentially lack B cells, showed indicative changes in 53 of the 265 biomarkers while none differed significantly. Hence, neither B cells nor BTK-dependent pathways in other cells seem to influence the levels of the studied plasma biomarkers in healthy donors. Regarding immune cells, the absolute number of T cells, including subsets, decreased, paralleling the decreasing tumor burden. T helper 1 (Th1) cell numbers dropped strongly, while Th2 cells remained relatively stable, causing Th2-skewing. Thus, long-term ibrutinib treatment has a profound impact on the plasma proteome and immune cells in patients with CLL.

Follicular Lymphoma-associated BTK Mutations are Inactivating Resulting in Augmented AKT Activation

PURPOSE

On the basis of the recent discovery of mutations in Bruton tyrosine kinase (BTK) in follicular lymphoma, we studied their functional properties.

EXPERIMENTAL DESIGN

We identified novel somatic BTK mutations in 7% of a combined total of 139 follicular lymphoma and 11 transformed follicular lymphoma cases, none of which had received prior treatment with B-cell receptor (BCR) targeted drugs. We reconstituted wild-type (WT) and mutant BTK into various engineered lymphoma cell lines. We measured BCR-induced signal transduction events in engineered cell lines and primary human follicular lymphoma B cells.

RESULTS

We uncovered that all BTK mutants destabilized the BTK protein and some created BTK kinase-dead mutants. The phospholipase C gamma 2 (PLCγ2) is a substrate of BTK but the BTK mutants did not alter PLCγ2 phosphorylation. Instead, we discovered that BTK mutants induced an exaggerated AKT phosphorylation phenotype in anti-Ig-treated recombinant lymphoma cell lines. The short hairpin RNA-mediated knockdown of BTK expression in primary human nonmalignant lymph node-derived B cells resulted in strong anti-Ig-induced AKT activation, as did the degradation of BTK protein in cell lines using ibrutinib-based proteolysis targeting chimera. Finally, through analyses of primary human follicular lymphoma B cells carrying WT or mutant BTK, we detected elevated AKT phosphorylation following surface Ig crosslinking in all follicular lymphoma B cells, including all BTK-mutant follicular lymphoma. The augmented AKT phosphorylation following BCR crosslinking could be abrogated by pretreatment with a PI3Kδ inhibitor.

CONCLUSIONS

Altogether, our data uncover novel unexpected properties of follicular lymphoma-associated BTK mutations with direct implications for targeted therapy development in follicular lymphoma.See related commentary by Afaghani and Taylor, p. 2123.

Targeting Solid Tumors With BTK Inhibitors

The repurposing of FDA-approved Bruton's tyrosine kinase (BTK) inhibitors as therapeutic agents for solid tumors may offer renewed hope for chemotherapy-resistant cancer patients. Here we review the emerging evidence regarding the clinical potential of BTK inhibitors in solid tumor therapy. The use of BTK inhibitors may through lead optimization and translational research lead to the development of new and effective combination regimens for metastatic and/or therapy-refractory solid tumor patients.

Ibrutinib in Patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma: A Retrospective Study

Limited treatment options are available for relapsed or refractory diffuse large B cell lymphoma (RR DLBCL). Few clinical studies have reported the use of Ibrutinib, a covalent Bruton Tyrosine kinase (BTK) inhibitor, in RR DLBCL. There are relatively few clinical studies about Ibrutinib in RR DLBCL now. We retrospectively investigated the safety and efficacy of Ibrutinib (alone or in combination with other drugs) in patients with RR DLBCL. We reviewed the medical records of 40 RR DLBCL patients who received Ibrutinib alone or in combination with other drugs in our hospital from June 2018 to August 2020. The objective response rate (ORR) of RR DLBCL patients on Ibrutinib was 22.5%. The median progression free survival time (PFS) was 13.0 months (95% CI 8.914–17.086), and the median overall survival time (OS) was 15.0 months (95% CI 11.931–18.089). Rash (25.0%) and fatigue (25.0%) were the most common adverse reactions in this study. The application of Ibrutinib to patients with RR DLBCL has good short-term efficacy, and the adverse reactions are well tolerated. Combined treatment of Ibrutinib with other drugs has been found to more effective than Ibrutinib therapy alone.