Cardiotoxicity of BTK inhibitors: ibrutinib and beyond

Severe infections in patients with chronic lymphocytic leukemia included in trials investigating BTK and BCL2 inhibitors

Bruton tyrosine kinase inhibitors (BTKi) and the BCL-2 inhibitor venetoclax have significantly improved the prognosis of patients with chronic lymphocytic leukemia (CLL). However, the incidence of severe infections in patients receiving these agents needs to be better understood. Our review aimed to provide an overview of grade ≥3 infections in patients with CLL who received BTKi and venetoclax-based therapy in prospective trials. Infection rates were influenced by the age of patients and the duration of follow-up. For treatment-naive (TN) patients receiving BTKi, infection rates ranged between 11.4 % and 27.4 % and were close to 30 % in relapsed/refractory (R/R) patients. TN and R/R patients receiving fixed-duration venetoclax-based treatments showed variable rates, with maximum values around 20 %. Opportunistic and fatal infections were uncommon. In conclusion, infections remain a concern in patients with CLL receiving targeted agents. A better definition of factors increasing infection vulnerability could help identify those patients who require infection prophylaxis.

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.

Bruton tyrosine kinase inhibitor-related atrial fibrillation and its implications in the treatment of B-cell lymphoma

Adverse events of atrial fibrillation (AF) have been commonly reported in lymphoma patients in treating Bruton's tyrosine kinase inhibitors (BTKi). The incidence rate of AF can vary depending on the specific types of BTKi and the patient population. Totally 45 published studies have revealed that the overall incidence rate of AF is 5% (95% CI 4%-7%). By performing a subtype single-rate analysis, the second-generation BTKi shows a lower AF incidence rate and lower cardiovascular toxicity. In the subtype single-rate analysis, we conclude the different AF incidence rates of Ibrutinib (10%, 95% CI 7%-13%), Acalabrutinib (4%, 95% CI 1%-6%), Orelabrutinib (0%, 95% CI 0%-1%), and Zanubrutinib (0%, 95% CI 0%-1%). The comprehensive analysis of AF inspires us to better predict and manage AF and other cardiovascular events in treating lymphoma. Meticulous evaluation, collaboration between cardiologists and hematologists, and discovery of new biomarkers are essential for its management.

Applied Cardio-Oncology in Hematological Malignancies: A Narrative Review

Applied cardio-oncology in hematological malignancies refers to the integration of cardiovascular care and management for patients with blood cancer, particularly leukemia, lymphoma, and multiple myeloma. Hematological cancer therapy-related cardiotoxicity deals with the most common cardiovascular complications of conventional chemotherapy, targeted therapy, immunotherapy, chimeric antigen receptor T (CAR-T) cell and tumor-infiltrating lymphocyte therapies, bispecific antibodies, and hematopoietic stem cell transplantation. This narrative review focuses on hematological cancer-therapy-related cardiotoxicity's definition, risk stratification, multimodality imaging, and use of cardiac biomarkers to detect clinical and/or subclinical myocardial dysfunction and electrical instability. Moreover, the most common cardiotoxic profiles of the main drugs and/or therapeutic interventions in patients with hematological malignancies are described thoroughly.

Which is the top player for the cardiovascular safety? ibrutinib vs. obinutuzumab in CLL

Introduction: Ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, is authorized for the treatment of chronic lymphocytic leukemia (CLL). This study aims to explore the cardiac safety profile of ibrutinib in comparison with obinutuzumab. Methods: A retrospective pharmacovigilance study was conducted on data retrieved from the European pharmacovigilance database (Eudravigilance) from 1 January 2014 to 30 September 2022. To compare the reporting frequency of cardiovascular events among ibrutinib, obinutuzumab, and the combination of both. Results: A total of 2 291 CV cases were retrieved, of which 1965 were related to ibrutinib, 312 to obinutuzumab, and 14 to the combination. Most cases referred to patients aged ≥65 years (N = 1,454; 63.47%) and male (N = 1,497; 65.34%). Most cases were serious (N = 2,131; 93.02%). The most reported events were: atrial fibrillation (N = 913; 31.31%) and haemorrhage (N = 201; 6.89%). A higher reporting frequency of CV events was found when ibrutinib was compared to obinutuzumab (ROR, 3.22; 95% CI, 2.89-3.60) or combination (ROR, 1.77; 95% CI, 1.11-2.83). A lower reporting was observed when obinutuzumab was compared to combination (ROR, 0.55; 95% CI, 0.34-0.88). Discussion: A higher reporting frequency of CV events in patients exposed to ibrutinib in comparison with obinutuzumab was found. Further studies are needed to better explore the safety of ibrutinib.

Pharmacovigilance analysis of cardiac risks associated with Bruton tyrosine kinase inhibitors

BACKGROUND

Bruton tyrosine kinase inhibitors (BTKIs) can be associated with several cardiac risks.

RESEARCH DESIGN AND METHODS

The study was conducted based on records from a large spontaneous reporting database, the Food and Drug Administration Adverse Event Reporting System, for cardiac events reported for several BTKI agents. Reporting odds ratio and information components based on statistical shrinkage transformation were utilized to measure disproportionality.

RESULTS

The final number of records for BTKI-related cardiac events was 10 320. Death or life-threatening events occurred in 17.63% of all associated cardiac records. Significant reporting was captured between BTKI (total/specific) and cardiac events, with the strongest association for ibrutinib. A total of 47 positive signals were evacuated for ibrutinib, with atrial fibrillation being the most commonly reported one. Concomitantly, cardiac failure, congestive, cardiac disorder, arrhythmia, pericardial effusion, and atrial flutter were also noticed for relatively stronger signal and disproportionality. Atrial fibrillation was over-reported in the three groups (ibrutinib, acalabrutinib, and zanubrutinib), and acalabrutinib had statistically significant lower reporting compared with ibrutinib.

CONCLUSIONS

Receiving ibrutinib, acalabrutinib, or zanubrutinib might increase the chance of cardiac complications, with ibrutinib posing the highest risk. The type of cardiotoxicity involved in ibrutinib was highly variable.

Targeted Small Molecules for Systemic Lupus Erythematosus: Drugs in the Pipeline

Despite the uncertainty of the pathogenesis of systemic lupus erythematosus, novel small molecules targeting specific intracellular mechanisms of immune cells are being developed to reverse the pathophysiological processes. These targeted molecules have the advantages of convenient administration, lower production costs, and the lack of immunogenicity. The Janus kinases, Bruton's tyrosine kinases, and spleen tyrosine kinases are important enzymes for activating downstream signals from various receptors on immune cells that include cytokines, growth factor, hormones, Fc, CD40, and B-cell receptors. Suppression of these kinases impairs cellular activation, differentiation, and survival, leading to diminished cytokine actions and autoantibody secretion. Intracellular protein degradation by immunoproteasomes, levered by the cereblon E3 ubiquitin ligase complex, is an essential process for the regulation of cellular functions and survival. Modulation of the immunoproteasomes and cereblon leads to depletion of long-lived plasma cells, reduced plasmablast differentiation, and production of autoantibodies and interferon-α. The sphingosine 1-phosphate/sphingosine 1-phosphate receptor-1 pathway is responsible for lymphocyte trafficking, regulatory T-cell/Th17 cell homeostasis, and vascular permeability. Sphingosine 1-phosphate receptor-1 modulators limit the trafficking of autoreactive lymphocytes across the blood-brain barrier, increase regulatory T-cell function, and decrease production of autoantibodies and type I interferons. This article summarizes the development of these targeted small molecules in the treatment of systemic lupus erythematosus, and the future prospect for precision medicine.

Next Generation BTK Inhibitors in CLL: Evolving Challenges and New Opportunities

Ibrutinib revolutionized the CLL treatment approach and prognosis demonstrating its efficacy and safety even at extended follow-up. During the last few years, several next-generation inhibitors have been developed to overcome the occurrence of toxicity or resistance in patients on continuous treatment. In a head-to-head comparison of two phase III trials, both acalabrutinib and zanubrutinib demonstrated a lower incidence of adverse events in respect to ibrutinib. Nevertheless, resistance mutations remain a concern with continuous therapy and were demonstrated with both first- and next-generation covalent inhibitors. Reversible inhibitors showed efficacy independently of previous treatment and the presence of BTK mutations. Other strategies are currently under development in CLL, especially for high-risk patients, and include BTK inhibitor combinations with BCl2 inhibitors with or without anti-CD20 monoclonal antibodies. Finally, new mechanisms for BTK inhibition are under investigations in patients progressing with both covalent and non-covalent BTK and BCl2 inhibitors. Here we summarize and discuss results from main experiences on irreversible and reversable BTK inhibitors in CLL.

Ibrutinib-Associated Cardiotoxicity: From the Pharmaceutical to the Clinical

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