CRISPR-Cas9 Knockout Screens Identify DNA Damage Response Pathways and BTK as Essential for Cisplatin Response in Diffuse Large B-Cell Lymphoma.

The recurrence of diffuse large B-cell lymphoma (DLBCL) has been observed in 40% of cases. The standard of care for refractory/relapsed DLBCL (RR-DLBCL) is platinum-based treatment prior to autologous stem cell transplantation; however, the prognosis for RR-DLBCL patients remains poor. Thus, to identify genes affecting the cisplatin response in DLBCL, cisplatin-based whole-genome CRISPR-Cas9 knockout screens were performed in this study. We discovered DNA damage response (DDR) pathways as enriched among identified sensitizing CRISPR-mediated gene knockouts. In line, the knockout of the nucleotide excision repair genes XPA and ERCC6 sensitized DLBCL cells to platinum drugs irrespective of proliferation rate, thus documenting DDR as essential for cisplatin sensitivity in DLBCL. Functional analysis revealed that the loss of XPA and ERCC6 increased DNA damage levels and altered cell cycle distribution. Interestingly, we also identified BTK, which is involved in B-cell receptor signaling, to affect cisplatin response. The knockout of BTK increased cisplatin sensitivity in DLBCL cells, and combinatory drug screens revealed a synergistic effect of the BTK inhibitor, ibrutinib, with platinum drugs at low concentrations. Applying local and external DLBCL cohorts, we addressed the clinical relevance of the genes identified in the CRISPR screens. BTK was among the most frequently mutated genes with a frequency of 3-5%, and XPA and ERCC6 were also mutated, albeit at lower frequencies. Furthermore, 27-54% of diagnostic DLBCL samples had mutations in pathways that can sensitize cells to cisplatin. In conclusion, this study shows that XPA and ERCC6, in addition to BTK, are essential for the response to platinum-based drugs in DLBCL.

Bruton's tyrosine kinase (BTK) inhibitors alter blood glucose and insulin in obese mice but reduce inflammation independent of BTK.

Obesity is associated with metabolic inflammation, which can contribute to insulin resistance, higher blood glucose and higher insulin indicative of prediabetes progression. The nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is a metabolic danger sensor implicated in metabolic inflammation. Many features of metabolic disease can activate of the NLRP3 inflammasome; however, it is not yet clear which upstream trigger to target, and there are no clinically approved NLRP3 inflammasome inhibitors for metabolic disease. Bruton's tyrosine kinase (BTK) mediates activation of the NLRP3 inflammasome. Ibrutinib is the most-studied pharmacological inhibitor of BTK and it can improve blood glucose control in obese mice. However, inhibitors of tyrosine kinases are permissive, and it is unknown if BTK inhibitors require BTK to alter endocrine control of metabolism or metabolic inflammation. We tested whether ibrutinib and acalabrutinib, a new generation BTK inhibitor with higher selectivity, require BTK to inhibit the NLRP3 inflammasome, metabolic inflammation and blood glucose in obese mice. Chronic ibrutinib administration lowered fasting blood glucose and improved glycemia, while acalabrutinib increased blood insulin levels and increased markers of insulin resistance in high-fat fed CBA/J mice with intact Btk. These metabolic effects of BTK inhibitors were absent in CBA/CaHN-Btkxid/J mice with mutant Btk. However, ibrutinib and acalabrutinib reduced NF-κB activity pro-inflammatory gene expression and NLRP3 inflammasome activation in macrophages with and without functional BTK. These data highlight the BTK inhibitors can have divergent effect on metabolism and separate effects on metabolic inflammation that can occur independently of actions on BTK.

Central nervous system involvement in chronic lymphocytic leukemia: a case report and review of literature.

BACKGROUND: Central nervous system involvement in chronic lymphocytic leukemia rarely occurs, and there is no standard therapy for central nervous system involvement in chronic lymphocytic leukemia. This article aims to analyze the diagnosis and treatment of central nervous system involvement in chronic lymphocytic leukemia. CASE PRESENTATION: It reports two cases of central nervous system involvement in chronic lymphocytic leukemia describing the clinical course, therapy, and prognosis. Case 1 is a 67-year-old Asian male patient, he experienced complications with central nervous system involvement after developing resistance to ibrutinib, bendamustine, and rituximab (BR) chemotherapies. The central nervous system lesion was controlled with high-dose methotrexate combined with pomalidomide, but Richter transformation occurred several months later. Case 2 is a 62-year-old Asian female patient, she had central nervous system involvement at initial diagnosis, and bone marrow and central nervous system lesions were controlled by ibrutinib therapy. CONCLUSION: Central nervous system involvement in chronic lymphocytic leukemia is rare and can be diagnosed on the basis of clinical features, cerebrospinal fluid testing, and radiographic evaluation. Ibrutinib, pomalidomide, and other drugs that can cross the blood-brain barrier may be effective for treating central nervous system involvement in chronic lymphocytic leukemia.

BTK acts as a modulator of the response to imatinib in chronic myeloid leukemia.

The use of tyrosine kinase inhibitors, such as imatinib, against the chronic myeloid leukemia (CML)-causing kinase BCR::ABL1 has become the model for successful targeted therapy. Nevertheless, drug resistance remains a clinical problem. Analysis of genome-wide expression and genetic aberrations of an in vitro imatinib-resistant CML cell line revealed downregulation of Bruton's tyrosine kinase (BTK), predominantly associated with B cell malignancies, and a novel BTK kinase domain variant in imatinib resistance. This raised the question of the role of BTK in imatinib-resistant CML. In the present study, BTK downregulation and the presence of the BTK variant c.1699_1700delinsAG p.(Glu567Arg) were confirmed in imatinib resistance in vitro. Similarly, BTK inhibition or small interfering RNA-mediated BTK knockdown reduced imatinib susceptibility by 84 and 71%, respectively. BTK overexpression was detrimental to CML cells, as proliferation was significantly reduced by 20.5% under imatinib treatment. In addition, BTK rescue in imatinib-resistant cells restored imatinib sensitivity. The presence of the BTK p.(Glu567Arg) variant increased cell numbers (57%) and proliferation (37%) under imatinib exposure. These data demonstrate that BTK is important for the development of imatinib resistance in CML: Its presence increased drug response, while its absence promotes imatinib resistance. Moreover, the BTK p.(Glu567Arg) variant abrogates imatinib sensitivity. These findings demonstrate a context-dependent role for BTK as an oncogene in B cell malignancies, but as a tumor suppressor in other neoplasms.

Sustained Response of Ibrutinib in a Patient with Waldenstrom Macroglobulinemia Presenting with Myasthenic Crisis as a Paraneoplastic Neurological Syndrome: A Case Report and Review of Literature.

Paraneoplastic syndrome is a broad spectrum of signs and symptoms due to neoplasm, attributed to substances produced by tumor cells, or in response to it. Myasthenia gravis (MG) is a well-known paraneoplastic neurological syndrome (PNS), frequently associated with thymic abnormalities, but rarely reported in patients with lymphoplasmacytic lymphoma.This study presents the case of a 52-year-old Indonesian male patient who was diagnosed with Waldenstrom macroglobulinemia (WM), a rare B-cell neoplasm, after developing a new onset of MG with myasthenic crisis. the patient's MG features improved with Ibrutinib as a treatment targeted toward cancer. This is the first case report presenting the treatment response of Ibrutinib in WM with myasthenic crisis. The literature was reviewed to explain the possibility of MG as a paraneoplastic syndrome of WM and the treatment response of Ibrutinib for this patient, as well as summarizing previous case reports of concomitant MG and WM.MG should be considered a paraneoplastic malignancy syndrome, including WM, during diagnostic workup. Ibrutinib should also be considered when available to patients, due to its adequate response in both previously treated and treatment naïve patients.

Impact of therapeutic inhibition of oncogenic cell signaling tyrosine kinase on cell metabolism: in vivo-detectable metabolic biomarkers of inhibition.

BACKGROUND: Inhibition of kinases is the ever-expanding therapeutic approach to various types of cancer. Typically, assessment of the treatment response is accomplished by standard, volumetric imaging procedures, performed weeks to months after the onset of treatment, given the predominantly cytostatic nature of the kinase inhibitors, at least when used as single agents. Therefore, there is a great clinical need to develop new monitoring approaches to detect the response to kinase inhibition much more promptly. Noninvasive 1H magnetic resonance spectroscopy (MRS) can measure in vitro and in vivo concentration of key metabolites which may potentially serve as biomarkers of response to kinase inhibition. METHODS: We employed mantle cell lymphoma (MCL) cell lines demonstrating markedly diverse sensitivity of inhibition of Bruton's tyrosine kinase (BTK) regarding their growth and studied in-depth effects of the inhibition on various aspects of cell metabolism including metabolite synthesis using metabolomics, glucose and oxidative metabolism by Seahorse XF technology, and concentration of index metabolites lactate, alanine, total choline and taurine by 1H MRS. RESULTS: Effective BTK inhibition profoundly suppressed key cell metabolic pathways, foremost pyrimidine and purine synthesis, the citrate (TCA) cycle, glycolysis, and pyruvate and glutamine/alanine metabolism. It also inhibited glycolysis and amino acid-related oxidative metabolism. Finally, it profoundly and quickly decreased concentration of lactate (a product of mainly glycolysis) and alanine (an indicator of amino acid metabolism) and, less universally total choline both in vitro and in vivo, in the MCL xenotransplant model. The decrease correlated directly with the degree of inhibition of lymphoma cell expansion and tumor growth. CONCLUSIONS: Our results indicate that BTK inhibition exerts a broad and profound suppressive effect on cell metabolism and that the affected index metabolites such as lactate, alanine may serve as early, sensitive, and reliable biomarkers of inhibition in lymphoma patients detectable by noninvasive MRS-based imaging method. This kind of imaging-based detection may also be applicable to other kinase inhibitors, as well as diverse lymphoid and non-lymphoid malignancies.

Stability Studies of Amorphous Ibrutinib Prepared Using the Quench-Cooling Method and Its Dispersions with Soluplus®.

The successful development of an amorphous form of a drug demands the use of process conditions and materials that reduce their thermodynamic instability. For the first time, we have prepared amorphous ibrutinib using the quench-cooling method with very high process efficiency. In the presented study, different formulations of amorphous active pharmaceutical ingredient (API) with Soluplus (SOL) in various weight ratios 1:9, 3:7, and 1:1 were prepared. The obtained samples were stored under long-term (25 ± 2 °C/60%RH ± 5% RH, 12 months) and accelerated (40 ± 2 °C/75%RH ± 5% RH, 6 months) storage conditions. The physical stability of amorphous ibrutinib and ibrutinib-Soluplus formulations was analyzed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), powder X-ray diffraction analysis (XRPD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The lack of significant interactions between the ingredients of the formulation was confirmed by FTIR analysis. An increase in moisture content with an increasing SOL weight ratio was observed under accelerated aging and long-term conditions. Additionally, a slight increase in the moisture content of the stored sample compared to that at the initial time was observed. The results revealed the physical strength of the polymeric systems in the presence of high humidity and temperature. The observed high thermal stability allows the use of various technological processes without the risk of thermal degradation.

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.

Pemphigus Vulgaris Treated With Ibrutinib: A Case Report.

Pemphigus vulgaris (PV) stands as a rare autoimmune disorder characterized by blistering and erosion of mucocutaneous membranes. The pathogenesis of PV implicates both B and T cells, which target cell-to-cell adhesion molecules within the epithelia of the skin and oral mucosa, leading to acantholysis. Typically, the presentation involves blistering of the oral mucosa, often followed by cutaneous lesions. Given the considerable risk of morbidity and mortality associated with PV, early diagnosis is crucial, typically relying on a combination of clinical features, histopathology, and direct immunofluorescence. Bruton tyrosine kinase (BTK) plays a significant role in the pathophysiology of autoimmune diseases and inflammation. Herein, we present a case of PV that demonstrated resistance to first-line therapy with steroids. Subsequently, treatment with the BTK inhibitor ibrutinib was initiated, yielding favorable outcomes. This case underscores the potential of targeted therapies, such as BTK inhibitors, in managing PV refractory to conventional treatment modalities.

In-vivo pharmacokinetic study of ibrutinib-loaded nanostructured lipid carriers in rat plasma by sensitive spectrofluorimetric method using harmonized approach of quality by design and white analytical chemistry.

Ibrutinib, an antineoplastic agent tackling chronic lymphocytic leukemia, mantle cell lymphoma, and Waldenstrom's Macroglobulinemia, falls under the category of BCS class II drugs, characterized by a puzzling combination of low solubility and high permeability. Its oral bioavailability remains a perplexing challenge, merely reaching 2.9 % due to formidable first-pass metabolism hurdles. In a bid to surmount this obstacle, researchers embarked on a journey to develop ibrutinib-loaded NLCs (Nanostructured Lipid Carriers) using a methodology steeped in complexity: a Design of Experiments (DoE)-based hot melted ultrasonication approach. Despite a plethora of methods for analyzing ibrutinib in various matrices, the absence of a spectrofluorimetric method for assessing it in rat plasma added to the enigma. Thus emerged a spectrofluorimetric method, embodying principles of white analytical chemistry and analytical quality by design, employing a Placket-Burman design for initial method exploration and a central composite design for subsequent refinement. This method underwent rigorous validation in accordance with ICH guidelines, paving the way for its application in scrutinizing the in-vivo pharmacokinetics of ibrutinib-loaded NLCs, juxtaposed against commercially available formulations. Surprisingly, the optimized NLCs exhibited a striking 1.82-fold boost in oral bioavailability, shedding light on their potential efficacy. The environmental impact of this method was scrutinized using analytical greenness tools, affirming its eco-friendly attributes. In essence, the culmination of these efforts has not only propelled advancements in drug bioavailability but also heralded the dawn of a streamlined and environmentally conscious analytical paradigm.

Targeting sphingolipid metabolism in chronic lymphocytic leukemia.

Elevated levels of circulating C16:0 glucosylceramides (GluCer) and increased mRNA expression of UDP-glucose ceramide glycosyltransferase (UGCG), the enzyme responsible for converting ceramides (Cer) to GluCer, represent unfavorable prognostic markers in chronic lymphocytic leukemia (CLL) patients. To evaluate the therapeutic potential of inhibiting GluCer synthesis, we genetically repressed the UGCG pathway using in vitro models of leukemic B cells, in addition to UGCG pharmacological inhibition with approved drugs such as eliglustat and ibiglustat, both individually and in combination with ibrutinib, assessed in cell models and primary CLL patient cells. Cell viability, apoptosis, and proliferation were evaluated in vitro, and survival and apoptosis were examined ex vivo. UGCG inhibition efficacy was confirmed by quantifying intracellular sphingolipid levels through targeted lipidomics using mass spectrometry. Other inhibitors of sphingolipid biosynthesis pathways were similarly assessed. Blocking UGCG significantly decreased cell viability and proliferation, highlighting the oncogenic role of UGCG in CLL. The efficient inhibition of UGCG was confirmed by a significant reduction in GluCer intracellular levels. The combination of UGCG inhibitors with ibrutinib demonstrated synergistic effect. Inhibitors that target alternative pathways within sphingolipid metabolism, like sphingosine kinases inhibitor SKI-II, also demonstrated promising therapeutic effects both alone and when used in combination with ibrutinib, reinforcing the oncogenic impact of sphingolipids in CLL cells. Targeting sphingolipid metabolism, especially the UGCG pathway, represents a promising therapeutic strategy and as a combination therapy for potential treatment of CLL patients, warranting further investigation.

A retrospective observational study of ibrutinib in chronic lymphocytic leukaemia in a real-life setting in France using the national claims database (OSIRIS).

BACKGROUND: Ibrutinib is a Bruton's tyrosine kinase inhibitor indicated for the first-line treatment and relapse of chronic lymphocytic leukaemia (CLL), Waldenström's macroglobulinemia (WM) and mantle cell lymphoma (MCL). This study aimed to describe the characteristics of CLL patients treated with ibrutinib and its effectiveness, safety, and treatment pattern in real life. METHODS: All patients covered by the general health scheme (approximately 80% of the French population) with a first ibrutinib dispensation from August 1, 2017 (date of reimbursement in France) to December 31, 2020, were identified in the French National Health Insurance database (SNDS). An algorithm was developed to identify the disease (CLL, MCL or WM) for which ibrutinib was prescribed. This article focused on CLL patients. The time to next treatment (TTNT) was plotted using Kaplan‒Meier curves. RESULTS: During this period, 6,083 patients initiated ibrutinib, among whom 2,771 (45.6%) patients had CLL (mean age of 74 years; 61% of men). At ibrutinib initiation, 46.6% of patients had a cardiovascular comorbidity. Most patients (91.7%) were not hospitalized during the exposure period for one of the cardiovascular or bleeding events studied. Hospitalizations were more frequent in patients with a cardiovascular comorbidity (5.9% versus 11.0%, p-value < 0.0001) and aged over 70 (5.9% versus 9.4%, p-value < 0.0001). The median TTNT was not reached. CONCLUSION: This is one of the largest cohorts of ibrutinib-treated patients in the world. The profile of CLL patients treated with ibrutinib was in accordance with the marketing authorization and reimbursement. This study confirmed effectiveness and safety data.

Real-World Treatment Patterns, Survival, and Economic Burden Among Elderly MCL Patients Previously Treated With cBTKis.

BACKGROUND: While covalent Bruton's tyrosine kinase inhibitors (cBTKis) have become a standard of care treatment for relapsed/refractory mantle cell lymphoma (R/R MCL), response duration is limited and resistance to BTKi and/or adverse events develop in a subset of patients. However, little real-world evidence on post-cBTKi clinical and economic outcomes exists for these patients. PATIENTS AND METHODS: This retrospective study used 2010 to 2019 U.S. Medicare claims, to identify elderly (≥ 66 years) patients with newly-diagnosed MCL who received third-line (3L) treatment and had evidence of cBTKi use in a prior line of therapy. Outcomes were assessed ≥ 12-months post 3L-treatment initiation and included treatment patterns, all-cause and MCL-related HRU and costs, and overall survival. RESULTS: The final sample contained 230 elderly patients with R/R MCL receiving 3L treatment who had cBTKi use in a prior line of therapy (mean age 75.0, 21.7% age > 80 years; 67.4% male; 93.9% White). Common 3L treatments included chemotherapy (26.1%), lenalidomide (18.7%), and bortezomib (18.3%); 1-quarter (25.7%) of patients received a cBTKi (17.8% ibrutinib; 7.8% acalabrutinib). Overall survival was poor from 3L treatment initiation (median OS = 9.4 months; 1-years survival rate = 43.7%). Patients exhibited high rates of HRU (73.6% experienced hospitalization) and substantial costs ($145,726) in the 12-months after 3L initiation. CONCLUSION: A large unmet need exists in this patient subpopulation, highlighting the importance of ongoing development of novel therapeutics.

Health-related quality of life in patients with Waldenström macroglobulinemia: results from the ASPEN trial.

Aim ASPEN is a randomized, open-label, Phase III study comparing zanubrutinib and ibrutinib in patients with Waldenström macroglobulinemia (WM). Materials & methods: Patient-reported outcomes were exploratory end points assessed using the EORTC QLQ-C30 and EQ-5D-5L VAS scores. Results: Overall, 201 patients (102 zanubrutinib; 99 ibrutinib) were enrolled. Clinically meaningful differences were observed in diarrhea and nausea/vomiting in both the intent-to-treat population and in patients attaining very good partial response (VGPR) in earlier cycles of treatment, as well as in long-term physical functioning and fatigue in patients achieving VGPR. Conclusion: Treatment with zanubrutinib was associated with greater improvements in health-related quality of life compared with ibrutinib in patients with WM and MYD88 mutations.Clinical Trial Registration: NCT03053440 (ClinicalTrials.gov).

Patient quality of life is importantWhat is this article about? This article talks about a study called the ASPEN trial, which compares two medicines used for treating a rare blood cancer that doctors call Waldenström macroglobulinemia. The medicines are called zanubrutinib (ZAN) and ibrutinib (IBR). They work in the same way, by blocking a protein called Bruton tyrosine kinase. When patients take medicines for an illness, it is important to learn about their physical, social, emotional and mental well-being (quality of life). In this study, we asked patients to fill out questionnaires about their well-being before starting the study treatment for their blood cancer, and again a few times while taking the medication, to see if there were any changes.What were the results of the study? There were two groups of patients. One group took ZAN and the other took IBR. The patients could not choose which medicine they were going to take. Results from both groups of patients were compared. Patients taking ZAN did not feel worse or better about their diarrhea and sickness, but those taking IBR said these symptoms had become worse. Both medicines improved how patients were feeling. However, improvement in tiredness and physical ability was larger in patients taking ZAN than those on IBR, especially for the patients whose cancer was getting better.What do the results mean? For patients with a rare blood cancer in this study, those taking ZAN had a better quality of life than those taking IBR.

Improved efficacy and safety of zanubrutinib versus ibrutinib in patients with relapsed/refractory chronic lymphocytic leukemia (R/R CLL) in China: a subgroup of ALPINE.

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) has different epidemiology in Chinese vs. Western patients, but there are few studies of CLL/SLL in large populations of Chinese patients. ALPINE is a global phase 3 trial investigating Bruton tyrosine kinase inhibitors zanubrutinib vs. ibrutinib to treat relapsed/refractory (R/R) CLL/SLL. Here we report results from the subgroup of Chinese patients. Adults with R/R CLL/SLL were randomized 1:1 to receive zanubrutinib (160 mg twice-daily) or ibrutinib (420 mg once-daily) until disease progression or unacceptable toxicity. Endpoints included overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. Data were analyzed descriptively. Ninety patients were randomized in China (zanubrutinib, n = 47; ibrutinib, n = 43). Baseline characteristics were balanced between groups, with fewer male patients in the zanubrutinib vs. ibrutinib group (55.3% vs. 69.8%). Median age was 60.5 years, 11% had del(17p) mutation, and 32% had tumor protein 53 (TP53) mutation. With median 25.3 months follow-up, ORR was 80.9% with zanubrutinib vs. 72.1% with ibrutinib. PFS was improved with zanubrutinib vs. ibrutinib (HR = 0.34 [95% CI, 0.15, 0.77]), and the HR for OS was 0.45 (95% CI, 0.14, 1.50). Rates of Grade ≥ 3 treatment-emergent adverse events (TEAEs; 64.4% vs. 72.1%), AEs leading to discontinuation (6.4% vs. 14.0%), and serious TEAEs (35.6% vs. 51.2%) were lower with zanubrutinib vs. ibrutinib. Zanubrutinib demonstrated improved ORR, PFS, and OS vs. ibrutinib and a more favorable safety profile in patients with R/R CLL/SLL in China. These results are consistent with the full global population of ALPINE. ClinicalTrials.gov: NCT03734016, registered November 7, 2018.

Treatment Sequencing in Chronic Lymphocytic Leukemia in 2024: Where We Are and Where We Are Headed.

As treatments with BTK inhibitors and BCL2 inhibitors have replaced the use of chemoimmunotherapy in CLL in both first-line and relapsed patients, it becomes critical to rationalize their use and exploit the full potential of each drug. Despite their proven, robust, and manifest efficacy, BTKis and BCL2is fail to provide long-term disease control in some categories of patients, and to date this is an unmet clinical need that is critical to recognize and address. Ongoing clinical trials are evaluating new treatment algorithms and new molecules to progressively thin this population. In this review for each category of patients we explicate the different possible patterns of treatment sequencing based on currently available evidence, starting from the frontline to currently ongoing trials, in order to optimize therapies as much as possible.

Arrhythmogenic Ventricular Remodeling by Next-Generation Bruton's Tyrosine Kinase Inhibitor Acalabrutinib.

Cardiac arrhythmias remain a significant concern with Ibrutinib (IBR), a first-generation Bruton's tyrosine kinase inhibitor (BTKi). Acalabrutinib (ABR), a next-generation BTKi, is associated with reduced atrial arrhythmia events. However, the role of ABR in ventricular arrhythmia (VA) has not been adequately evaluated. Our study aimed to investigate VA vulnerability and ventricular electrophysiology following chronic ABR therapy in male Sprague-Dawley rats utilizing epicardial optical mapping for ventricular voltage and Ca2+ dynamics and VA induction by electrical stimulation in ex-vivo perfused hearts. Ventricular tissues were snap-frozen for protein analysis for sarcoplasmic Ca2+ and metabolic regulatory proteins. The results show that both ABR and IBR treatments increased VA vulnerability, with ABR showing higher VA regularity index (RI). IBR, but not ABR, is associated with the abbreviation of action potential duration (APD) and APD alternans. Both IBR and ABR increased diastolic Ca2+ leak and Ca2+ alternans, reduced conduction velocity (CV), and increased CV dispersion. Decreased SERCA2a expression and AMPK phosphorylation were observed with both treatments. Our results suggest that ABR treatment also increases the risk of VA by inducing proarrhythmic changes in Ca2+ signaling and membrane electrophysiology, as seen with IBR. However, the different impacts of these two BTKi on ventricular electrophysiology may contribute to differences in VA vulnerability and distinct VA characteristics.

Good clinical response following Ibrutinib treatment of a rare case of lymphoplasmacytic lymphoma secreting IgA kappa paraprotein: A case report.

Lymphoplasmacytic lymphoma (LPL) is a malignant proliferation of small lymphocytes, lymphoplasmocytoid cells and plasmocytes affecting the bone marrow, lymph nodes and spleen. Its incidence is 1/100,000 and represents 8% of all lymphomas. A total of ~5% of patients with LPL may secrete non-IgM of IgG, IgA, kappa or lambda type or be non-secretory. In the present study, a case of a 62-year-old female patient who was diagnosed with non-IgM LPL with kappa light chain monoclonal paraprotein production and normal serum immunoglobulin levels was reported. The MYD88 L265P mutation was detected by molecular genetic analysis using a sample of the bone marrow. The patient underwent initial treatment with a combination of Bendamustine-Rituximab, and later on, Ibrutinib (a Bruton kinase inhibitor) was added to the treatment protocol. The authors' aim was to describe a case of a rare type of LPL studied and cured at the University Hospital 'St. Ivan Rilski', as well as to show the methods used for its diagnosis and their applicability. The difficulty in diagnosing such rare cases of LPL which are associated with marked plasmacytic differentiation and IgA paraprotein secretion resembling plasma cell neoplasia was addressed. From the other side, the characteristic features in favor of LPL diagnosis are the immunophenotype profile of plasmocytes, as well as the presence of MYD88 L265P mutation. Finally, the methods of management and treatment of this type of lymphoma were reported, highlighting the favorable effect of the treatment with Bruton TK inhibitor (Ibrutinib).