Three-year cardiovascular and non-cardiovascular adverse events in patients with chronic lymphocytic leukemia or small cell lymphocytic lymphoma treated with Bruton tyrosine kinase inhibitors acalabrutinib or ibrutinib: a real-world analysis.

Bruton tyrosine kinase (BTK) inhibitors play an important role in targeted treatment of B-cell lymphoproliferative disorders. However, adverse events may limit the proper course of treatment in many patients. The purpose of this study is to compare the risk of cardiovascular and non-cardiovascular adverse events in patients with chronic lymphocytic leukemia (CLL) or small cell lymphocytic lymphoma (SLL) treated with the first-generation BTK inhibitor ibrutinib versus second-generation acalabrutinib, using real-world data from a collaborative multinational network. We used data from the network (TriNetX), which encompasses more than 100 healthcare organizations worldwide. We queried the database for patients aged ≥ 18 years with chronic lymphocytic leukemia or small-cell lymphomas treated with ibrutinib or acalabrutinib in the past ten years before the analysis. We used propensity score matching to balance the cohorts. The 3-year cumulative incidences and hazard ratios for the following outcomes were calculated: atrial flutter or fibrillation, other arrhythmias, heart failure, ischemic stroke or peripheral embolism, acute coronary syndrome, bleeding, and sepsis. We compared 2,107 patients in each group. Atrial fibrillation or flutter occurred in 150 (7.1%) patients with acalabrutinib and 310 (14.7%) patients with ibrutinib during the 3-year follow-up (hazard ratio, 0.68, 95% CI 0.55-0.84). New-onset hypertension occurred in 342 (16.3%) patients in the acalabrutinib group and 584 (27.7%) patients in the ibrutinib group (hazard ratio 0.81, 95% CI 0.66-0.98). Sepsis was diagnosed in 136 (6.5%) patients in the acalabrutinib group versus 239 (11.3%) patients in the ibrutinib group (hazard ratio 0.77, 95 CI 0.60-0.98). The two groups had no significant differences concerning the other adverse events. In a large retrospective cohort using real-world data from electronic medical registers, patients with CLL or SLL treated with acalabrutinib had a better cardiovascular and non-cardiovascular safety profile than those treated with ibrutinib, with lower risks of atrial flutter or fibrillation, new-onset arterial hypertension, and sepsis.

Venetoclax-resistant CLL cells show a highly activated and proliferative phenotype.

Venetoclax treatment has demonstrated efficacy and a safety profile in chronic lymphocytic leukemia (CLL) patients, however the emergence of resistant cells is a current complication. We and others, previously reported that the activation of CLL cells by signals that mimic microenvironment stimuli favors the upregulation of anti-apoptotic proteins from B cell lymphoma-2 (BCL-2) family that are not targeted by venetoclax, reducing malignant cell sensitivity to the drug. We here studied venetoclax-resistant CLL cells generated in vitro by autologous activated T lymphocytes, and found that they showed an aggressive phenotype characterized by increased expression of activation and proliferation markers. Moreover, surviving cells expressed high levels of B cell lymphoma-extra-large (BCL-XL) and/or myeloid cell leukemia-1 (MCL-1), and a sustained resistance to a second treatment with the drug. Interestingly, the spleen tyrosine kinase (SYK) inhibitor entospletinib, and the phosphoinositide 3-kinase delta (PI3Kδ) inhibitor idelalisib, reduced T cell activation, impaired the generation of leukemic cells with this aggressive phenotype, and were able to restore CLL sensitivity to venetoclax. Our data highlight a novel combination to overcome resistance to venetoclax in CLL.