Ibrutinib

Efficacy and safety of Orelabrutinib-based regimens in diffuse large B-cell lymphoma: a single-center retrospective analysis

Currently, combining chemotherapy with Bruton tyrosine kinase inhibitors (BTKi) has demonstrated significant effectiveness in treating patients with diffuse large B-cell lymphoma. Orelabrutinib is a second-generation BTK inhibitor, and presently, there have been few reports of Orelabrutinib being used to treat DLBCL. We conducted a retrospective investigation to explore the safety and efficacy of Orelabrutinib in combination with chemotherapy or immunotherapy. The study comprised 19 patients with a median age of 61 years. The overall response rate (ORR) was 89.5% with a complete response (CR) rate of 73.7% and a partial response rate (PR) of 15.8%. The estimated 2-year overall survival (OS) and progression-free survival (PFS) rates were 78.6% (95%CI, 59.8%-100%) and 72.2% (95% CI, 52.4%-99.6%), respectively, with a median follow-up time of 11 months (range 2-24). The most prevalent grade 3 or 4 adverse events (AEs), neutropenia (52.6%), anemia (36.8%), thrombocytopenia (26.3%), febrile neutropenia (26.3%), and lung infection (10.5%), were the most common. Our results reveal that Orelabrutinib is an effective therapy for DLBCL patients. Furthermore, our first investigation of the Orelabrutinib application lays a foundation for larger retrospective studies.

Folic Acid-Modified Ibrutinib-Loaded Silk Fibroin Nanoparticles for Cancer Cell Therapy with Over-Expressed Folate Receptor

The anticancer drug ibrutinib (IB), also known as PCI-32765, is a compound that irreversibly inhibits Bruton's tyrosine kinase (BTK) and was initially developed as a treatment option for B-cell lineage neoplasms. Its action is not limited to B-cells, as it is expressed in all hematopoietic lineages and plays a crucial role in the tumor microenvironment. However, clinical trials with the drug have resulted in conflicting outcomes against solid tumors. In this study, folic acid-conjugated silk nanoparticles were used for the targeted delivery of IB to the cancer cell lines HeLa, BT-474, and SKBR3 by exploiting the overexpression of folate receptors on their surfaces. The results were compared with those of control healthy cells (EA.hy926). Cellular uptake studies confirmed total internalization of the nanoparticles functionalized by this procedure in the cancer cells after 24 h, compared to nanoparticles not functionalized with folic acid, suggesting that cellular uptake was mediated by folate receptors overexpressed in the cancer cells. The results indicate that the developed nanocarrier can be used for drug targeting applications by enhancing IB uptake in cancer cells with folate receptor overexpression.

Evidence-based expert consensus on the management of primary central nervous system lymphoma in China

Primary central nervous system lymphoma (PCNSL) is a type of central nervous system restricted non-Hodgkin lymphoma, whose histopathological diagnosis is majorly large B cell lymphoma. To provide specific, evidence-based recommendations for medical professionals and to promote more standardized, effective and safe treatment for patients with PCNSL, a panel of experts from the Chinese Neurosurgical Society of the Chinese Medical Association and the Society of Hematological Malignancies of the Chinese Anti-Cancer Association jointly developed an evidence-based consensus. After comprehensively searching literature and conducting systematic reviews, two rounds of Delphi were conducted to reach consensus on the recommendations as follows: The histopathological specimens of PCNSL patients should be obtained as safely and comprehensively as possible by multimodal tomography-guided biopsy or minimally invasive surgery. Corticosteroids should be withdrawn from, or not be administered to, patients with suspected PCNSL before biopsy if the patient's status permits. MRI (enhanced and DWI) should be performed for diagnosing and evaluating PCNSL patients where whole-body PET-CT be used at necessary time points. Mini-mental status examination can be used to assess cognitive function in the clinical management. Newly diagnosed PCNSL patients should be treated with combined high-dose methotrexate-based regimen and can be treated with a rituximab-inclusive regimen at induction therapy. Autologous stem cell transplantation can be used as a consolidation therapy. Refractory or relapsed PCNSL patients can be treated with ibrutinib with or without high-dose chemotherapy as re-induction therapy. Stereotactic radiosurgery can be used for PCNSL patients with a limited recurrent lesion who were refractory to chemotherapy and have previously received whole-brain radiotherapy. Patients with suspected primary vitreoretinal lymphoma (PVRL) should be diagnosed by vitreous biopsy. PVRL or PCNSL patients with concurrent VRL can be treated with combined systemic and local therapy.

Waldenström Macroglobulinemia: Mechanisms of Disease Progression and Current Therapies

Waldenström macroglobulinemia is an indolent, B-cell lymphoma without a known cure. The bone marrow microenvironment and cytokines both play key roles in Waldenström macroglobulinemia (WM) tumor progression. Only one FDA-approved drug exists for the treatment of WM, Ibrutinib, but treatment plans involve a variety of drugs and inhibitors. This review explores avenues of tumor progression and targeted drug therapy that have been investigated in WM and related B-cell lymphomas.

Cryo-EM structure of the human IgM B cell receptor

The B cell receptor (BCR) initiates immune responses through antigen recognition. We report a 3.3-angstrom cryo-electron microscopy structure of human immunoglobulin M (IgM)-BCR in the resting state. IgM-BCR comprises two heavy chains, two light chains, and the Igα/Igβ heterodimer. The ectodomains of the heavy chains closely stack against those of Igα/Igβ, with one heavy chain locked between Igα and Igβ in the juxtamembrane region. Extracellular interactions may determine isotype specificity of the BCR. The transmembrane helices of IgM-BCR form a four-helix bundle that appears to be conserved among all BCR isotypes. This structure contains 14 glycosylation sites on the IgM-BCR ectodomains and reveals three potential surface binding sites. Our work reveals the organizational principles of the BCR and may facilitate the design of antibody-based therapeutics.

Late-Stage Functionalization for the Optimization of Reversible BTK Inhibitors

Late-stage functionalization (LSF) enables medicinal chemists to quickly explore structure–activity relationships (SAR) of novel analogues derived from a fully elaborated parent structure. Using several known C–H functionalization chemistries, we have systematically applied the LSF strategy to modify different regions of a Bruton’s tyrosine kinase (BTK) reversible inhibitor lead series. This approach allowed for broad SAR exploration across several key subunits of the molecule at positions that were previously difficult to explore with traditional synthesis, providing analogues with high potency and improved pharmacokinetic properties. This case study illustrates both the promise and the challenges associated with applying LSF to complex lead molecules.

Progressive multifocal leukoencephalopathy in the context of newer therapies in hematology and review of new treatment strategies

Progressive multifocal leukoencephalopathy (PML) is a rare, often fatal demyelinating disease of the central nervous system (CNS) caused by the reactivation of JC polyomavirus in the CNS. We present a case of a 54-year-old man with follicular lymphoma diagnosed with PML after being treated with anti-CD20 monoclonal antibody-based regimens for several years. Due to the lack of effective treatment choices for PML, the patient was treated with nivolumab, based on recent reports, but succumbed to his disease a few months after diagnosis. In this paper, we focus on reviewing the literature of PML cases correlated with newer agents used in hematology, possible factors affecting disease prognosis, as well as the available data on upcoming therapeutic options for patients with PML. Though newer promising treatments such as anti-PD1 monoclonal antibodies arise, a definitive treatment option is yet to be found. Vigilance, early detection, and prompt intervention play a crucial role in the prognosis of PML in patients with hematological malignancies.

A Novel Finding of Lichenoid Drug Reaction From Ibrutinib Therapy

Ibrutinib is Burton’s tyrosine kinase inhibitor used in the treatment of chronic lymphocytic leukemia and other conditions. This drug has been generally thought to be well tolerated, although studies have identified a few distinct adverse effects, including gastrointestinal discomfort, nausea, diarrhea, and atrial fibrillation. Regarding cutaneous findings, ibrutinib has only been linked to two self-limiting forms of mild rashes generally. In this report, we discuss a lichenoid drug reaction to ibrutinib in a patient with chronic lymphocytic leukemia severe enough to result in drug discontinuation. This adverse effect has not been previously reported to our knowledge.

Electrophilic warheads in covalent drug discovery: an overview

INTRODUCTION

Covalent drugs have been used for more than hundred years, but gathered larger interest in the last two decades. There are currently over a 100 different electrophilic warheads used in covalent ligands, and there are several considerations tailoring their reactivity against the target of interest, which is still a challenging task.

AREAS COVERED

This review aims to give an overview of electrophilic warheads used for protein labeling in chemical biology and medicinal chemistry. The warheads are discussed by targeted residues, mechanism and selectivity, and analyzed through three different datasets including our collection of warheads, the CovPDB database, and the FDA approved covalent drugs. Moreover, the authors summarize general practices that facilitate the selection of the appropriate warhead for the target of interest.

EXPERT OPINION

In spite of the numerous electrophilic warheads, only a fraction of them is used in current drug discovery projects. Recent studies identified new tractable residues by applying a wider array of warhead chemistries. However, versatile, selective warheads are not available for all targetable amino acids, hence discovery of new warheads for these residues is needed. Broadening the toolbox of the warheads could result in novel inhibitors even for challenging targets developing with significant therapeutic potential.

Current Treatment Options in CLL

After impressive developments in recent years with the rise of new targeted agents, chemoimmunotherapy (CIT) only plays a minor role in the treatment of patients with chronic lymphocytic leukemia (CLL). Inhibitors of the Bruton tyrosine kinase (BTK), such as ibrutinib or more recently acalabrutinib, are highly effective, even in poor-risk or chemo-refractory patients. Venetoclax, an inhibitor of the anti-apoptotic BCL2 protein and, to a lesser extent, phosphoinositide-3 kinase (PI3K) delta inhibitors, add to the armamentarium of targeted agents for the treatment of CLL. Furthermore, anti-CD20 monoclonal antibodies are used very successfully either alone or in combination with BTK, BCL2 or PI3K inhibitors. Despite these advances, there is still an ongoing pursuit for new therapeutic approaches in the treatment of CLL. An even bigger challenge poses the determination of the optimal combination and sequence of those drugs. Here, we give an overview of current treatment options in CLL, weighing the advantages and disadvantages of each approach in the light of different clinical settings.

Current Methods of Post-Translational Modification Analysis and Their Applications in Blood Cancers

Post-translational modifications (PTMs) add a layer of complexity to the proteome through the addition of biochemical moieties to specific residues of proteins, altering their structure, function and/or localization. Mass spectrometry (MS)-based techniques are at the forefront of PTM analysis due to their ability to detect large numbers of modified proteins with a high level of sensitivity and specificity. The low stoichiometry of modified peptides means fractionation and enrichment techniques are often performed prior to MS to improve detection yields. Immuno-based techniques remain popular, with improvements in the quality of commercially available modification-specific antibodies facilitating the detection of modified proteins with high affinity. PTM-focused studies on blood cancers have provided information on altered cellular processes, including cell signaling, apoptosis and transcriptional regulation, that contribute to the malignant phenotype. Furthermore, the mechanism of action of many blood cancer therapies, such as kinase inhibitors, involves inhibiting or modulating protein modifications. Continued optimization of protocols and techniques for PTM analysis in blood cancer will undoubtedly lead to novel insights into mechanisms of malignant transformation, proliferation, and survival, in addition to the identification of novel biomarkers and therapeutic targets. This review discusses techniques used for PTM analysis and their applications in blood cancer research.

Targeting the IL-2 inducible kinase in melanoma; a phase 2 study of ibrutinib in systemic treatment-refractory distant metastatic cutaneous melanoma: preclinical rationale, biology, and clinical activity (NCI9922)

BACKGROUND

IL-2 inducible kinase (ITK) is highly expressed in metastatic melanomas and its inhibition suppresses melanoma cell proliferation. We hypothesize that ibrutinib has a direct antitumor effect in melanoma cell lines and that treatment of metastatic melanomas with ibrutinib induces antitumor responses.

METHODS

We assessed the ibrutinib effect on melanoma cell proliferation, apoptosis, and motility. Patients with metastatic melanoma refractory to PD-1 and MAPK inhibitors (if BRAFV600-mutant) were treated with ibrutinib, 840 mg PO QD, as part of a phase II clinical trial (clinicaltrials.gov NCT02581930).

RESULTS

Melanoma cell lines frequently express ITK, YES1, and EGFR. Ibrutinib suppressed cell motility and proliferation in most cell lines. Eighteen patients (13 male; median age 63.5 years, range 37-82; 12 with ipilimumab resistance) were enrolled. The most frequent side effects were fatigue (61%), anorexia (50%), hyponatremia (28%), nausea, and vomiting (22% each). No antitumor responses were seen. At a median follow-up of 6 months (0.3-35.8 months), the median progression-free survival was 1.3 months (range 0.2-5.5 months). Fifteen patients were discontinued from the study due to progression, and 14 patients had died from metastatic melanoma. All archived tumors expressed ITK, 41% had no expression of p16 and PTEN, and 61% had absent tumor-infiltrating lymphocytes (TILs). Ibrutinib significantly suppressed proliferating (Ki67+) CD19+ peripheral blood mononuclear cells and had no significant effect on other lymphocyte subsets.

CONCLUSION

Ibrutinib did not induce any meaningful clinical benefit. ITK expression may not be clinically relevant. Treatment-refractory metastatic melanomas have other fundamental defects (i.e. absent PTEN and p16 expression, absent TILs) that may contribute to an adverse prognosis.

Current and novel BTK inhibitors in Waldenström's macroglobulinemia

The current therapeutic approach in Waldenström’s macroglobulinemia (WM) is being driven by insights in disease biology and genomic landscape. Bruton’s tyrosine kinase (BTK) plays a key role in signaling pathways for the survival of WM clone. BTK inhibition has changed the treatment landscape of the disease. Ibrutinib has resulted in deep and durable responses both as an upfront and salvage treatment with a manageable toxicity profile. However, the need for fewer off-target effects and deeper responses has resulted in the clinical development of second-generation BTK inhibitors. Zanubrutinib has resulted in clinically meaningful antitumor activity, including deep and durable responses, with a low discontinuation rate due to treatment-related toxicities. Cardiovascular adverse events seem to be milder compared with ibrutinib. Interestingly, the efficacy of zanubrutinib in WM is significant both for MYD88^L265P and MYD88^WT patients. Although the randomized, phase III ASPEN clinical trial did not meet its primary endpoint in terms of showing a superiority of zanubrutinib in deep responses compared with ibrutinib, secondary efficacy and safety endpoints underscore the potential clinical role of zanubrutinib in the treatment algorithm of WM independent of the MYD88 mutational status. Combination regimens and non-covalent BTK inhibitors are emerging as promising treatment strategies. Long-term data will determine whether next-generation BTK inhibitors are more potent and safer compared with ibrutinib, and whether they are able to overcome resistance to ibrutinib, either alone or in combination with inhibitors of other interrelated molecular pathways.

Novel Treatment Strategies in the Management of Waldenström Macroglobulinemia

PURPOSE OF REVIEW

Recent advances the genomic profiling of patients with Waldenström macroglobulinemia (WM) have led to the identification of novel therapeutic targets in these patients. In this review, we cover the current standard of care and the recently evaluated novel approaches with high potential to be incorporated in the therapeutic armamentarium against WM.

RECENT FINDINGS

The MYD88^L265P mutation is the most common genomic abnormality in WM, and is encountered in 80-95% of patients, making it an important target for drug development. The success of the first-generation Bruton tyrosine kinase (BTK) inhibitor, ibrutinib, has generated tremendous interest in the study of more selective and potent BTK inhibitors. Additionally, the identification of CXCR4^WHIM mutations in up to approximately 40% of patients with WM has fueled research regarding their implication on systemic therapy in WM. In a rapidly advancing field of targeted therapies, the treatment options for patients with WM are expanding as researchers continue to uncover and harness the survival pathways active in this hematologic malignancy.

The current role of BTK inhibitors in the treatment of Waldenstrom's Macroglobulinemia

INTRODUCTION

Waldenstrom's Macroglobulinemia (WM) is a rare, indolent lymphoplasmacytic lymphoma characterized by heterogeneous clinical and genomic profile. Bruton's tyrosine kinase (BTK) is central to the signaling pathways required for clonal WM cell survival, and BTK inhibitors currently have an imperative role in the treatment of WM.

AREAS COVERED

The central role of BTK in WM will be described, and the rationale behind the development of BTKi. Clinical trial data that led to the approval of ibrutinib (the first-in-class BTKi) will be reviewed. Despite its potency and safe toxicity profile, ibrutinib does not induce deep remissions, and responses are mutational-status dependent. The mechanisms that lead to resistance to this agent are being investigated. Ibrutinib treatment has to be continuous; consequently, patients face the effects of long-term toxicity. In that context, second-generation inhibitors are in clinical development with fewer off-target effects and an efficacy profile, which will be determined based on long-term follow-up data.

EXPERT OPINION

The optimal therapeutic approach for WM patients remains to be established. The question of whether a combinatory (or synergistic) regimen to overcome resistance and allow for a fixed treatment duration will allow for deep and durable response is being addressed in ongoing clinical trials.

PDGFD induces ibrutinib resistance of diffuse large B‑cell lymphoma through activation of EGFR

Ibrutinib, an FDA approved, orally administered BTK inhibitor, has demonstrated high response rates to diffuse large B-cell lymphoma (DLBCL), however, complete responses are infrequent and acquired resistance to BTK inhibition can emerge. The present study investigated the role of the platelet-derived growth factor D (PDGFD) gene and the ibrutinib resistance of DLBCL in relation to epidermal growth factor receptor (EGFR). Bioinformatics was used to screen and analyze differentially expressed genes (DEGs) in complete response (CR), partial response (PR) and stable disease (SD) in DLBCL treatment with ibrutinib, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to analyze enriched the signaling pathways increasing DEGs. The Search Tool for Interactions of Chemicals database was used to analyze the target genes of ibrutinib. An interaction network of DEGs, disease-related genes and ibrutinib was constructed. The expression of PDGFD in tissues that were resistant or susceptible to DLBCL/ibrutinib was detected via immunohistochemistry (IHC), and the expression of PDGFD in DLBCL/ibrutinib-resistant strains and their parental counterparts were examined via reverse transcription-quantitative PCR and western blot analyses. Subsequently, a drug-resistant cell model of DLBCL/ibrutinib in which PDGFD was silenced was constructed. The apoptosis of the DLBCL/ibrutinib-resistant strains was examined using MTT and flow cytometry assays. EGFR gene expression was then assessed. At the same time, a PDGFD-interfering plasmid and an EGFR overexpression plasmid were transfected into the DLBCL drug-resistant cells (TMD8-ibrutinib, HBL1-ibrutinib) separately or together. MTT was used to measure cell proliferation and changes in the IC₅₀ of ibrutinib. A total of 86 DEGs that increased in the CR, PR and SD tissues were screened, and then evaluated with GO and KEGG. The interaction network diagram showed that there was a regulatory relationship between PDGFD and disease-related genes, and that PDGFD could indirectly target the ibrutinib target gene EGFR, indicating that PDGFD could regulate DLBCL via EGFR. IHC results showed high expression of PDGFD in diffuse large B-cell lymphoma tissues with ibrutinib tolerance. PDGFD expression in ibrutinib-resistant DLBCL cells was higher compared with in parental cells. Following interference with PDGFD expression in ibrutinib-resistant DLBCL cells, the IC₅₀ value of ibrutinib decreased, the rate of apoptosis increased and EGFR expression decreased. In brief, EGFR overexpression can reverse the resistance of DLBCL to ibrutinib via PDGFD interference, and PDGFD induces the resistance of DLBCL to ibrutinib via EGFR.

Chimeric Antigen Receptor-Engineered T-Cells - A New Way and Era for Lymphoma Treatment

BACKGROUND

Patients with refractory or relapsed diffuse large B-cell lymphoma have a poor prognosis with the current standard of care.

OBJECTIVE

Chimeric Antigen Receptor T-cells (CAR T-cells) are functionally reprogrammed lymphocytes, which are able to recognize and kill tumor cells. The aim of this study is to make progress in this area.

METHODS

A mini-review was achieved using the articles published in Web of Science and PubMed in the last year and the new patents were made in this field.

RESULTS

The responses to CAR T-cell products axicabtagene ciloleucel and tisagenlecleucel are promising; the objective response rate can reach up to 83%, and the complete response rate ranges between 40 and 58%. About half of the patients may have serious side effects, such as cytokine release syndrome and neurotoxicity. Current and future developments include the improvement of CAR T-cell expansion and polyfunctionality, the combined use of CAR T-cells with a fusion protein between interferon and an anti-CD20 monoclonal antibody, with checkpoint inhibitors or small molecule sensitizers that have apoptotic-regulatory effects. Furthermore, the use of IL-12-expressing CAR T-cells, an improved technology for the production of CAR T-cells based on targeted nucleases, the widespread use of allogeneic CAR T-cells or universal CAR T-cells obtained from genetically engineered healthy donor T-cells are future developments actively considered.

CONCLUSION

CAR T-cell therapy significantly improved the outcome of patients with relapsed or refractory diffuse large B-cell lymphoma. The advances in CAR T-cells production technology will improve the results and enable the expansion of this new immunotherapy.

Evaluating ibrutinib in the treatment of symptomatic Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is a rare lymphoplasmacytic lymphoma with indolent course and prolonged disease course. The first-in-class Bruton's tyrosine kinase inhibitor, ibrutinib, has shown significant activity and a distinct adverse event profile among both newly diagnosed and relapsed/refractory WM patients. Interestingly, clinical responses to ibrutinib have been shown to be dependent on patients' MYD88 and CXCR4 mutational status. The recent outcomes of the Phase III iNNOVATE trial showed that the combination of ibrutinib with rituximab resulted in a significantly prolonged progression-free survival compared with rituximab monotherapy, which provides a novel therapeutic option in the clinical practice especially for the rituximab-refractory WM patients. However, the need for continuous drug administration along with the unique toxicity manifestations may render the patient management challenging. Furthermore, our understanding of the underlying resistant mechanisms to ibrutinib is currently being evolved.

Infection control in patients treated for chronic lymphocytic leukemia with ibrutinib or idelalisib: recommendations from Italian society of hematology

The introduction of new therapeutic agents in chronic lymphocytic leukemia (CLL), including the new kinase inhibitors (KIs) ibrutinib and idelalisib, has changed the therapeutic landscape of the disease. The new KIs have also changed frequency and epidemiology of infections, that represent a major cause of morbidity and mortality of the disease. Hence, the great strides in the indications and use of new KIs need parallel amelioration of prophylaxis and supportive treatment for infections. Moving from the recognition that infection control represents an unmet need, the Italian Society of Hematology (SIE) convened a panel of experts who had published and/or expressed an interest in infection complications in CLL. The goal of the project was to provide practice recommendations for the management of the infectious complications of CLL during ibrutinib or idelalisib therapy. The present publication represents the results of a series of email correspondences and meetings held during 2017 and 2018. Three domains of infectious complications during KIs therapy for CLL were explored: risk assessment, risk management and risk monitoring. We hope these recommendations will help to minimize infectious adverse events, and we believe that an optimal management of them will be rewarded by better outcomes, and better quality of life.

Chimeric antigen receptor T cell therapy and other therapeutics for malignancies: Combination and opportunity

Chimeric antigen receptor T (CAR-T) cell therapy provides possibility for the treatment of malignancies since clinical trials have shown that CAR-T therapy has a significant anti-tumor effect. Although many efforts have been made to improve the efficacy and reduce the side effects of CAR-T therapy, there are still many problems to solve. With the rapid development of this field, combination immunotherapy has been proved to improve the efficacy of CAR-T therapy. Studies have shown that radiotherapy, chemotherapy, oncolytic virotherapy, BTK inhibitors and immune checkpoint blockade-based therapy may further enhance the efficacy of CAR-T therapy while CRISPR/Cas9 technology and IL-1 blockade may improve the safety. In this review, we summarized the advantages and the mechanisms of the combination immunotherapy based on CAR-T cell therapy.