Vascular Impact of Cancer Therapies: The Case of BTK (Bruton Tyrosine Kinase) Inhibitors

Ibrutinib pharmacokinetics in B-lymphoproliferative disorders discloses exposure-related incidence of hypertension

OBJECTIVE

Ibrutinib has been the first Bruton tyrosine kinase inhibitor (BTKi) authorized for the treatment of B-cell lymphoproliferative disorders (B-LPDs). Numerous publications have confirmed the efficacy of this orally administrated drug in chemo-free regimens for B-LPDs. They also reported several adverse events (AE) associated with ibrutinib treatment. Whether these AEs depended on ibrutinib exposure has however been seldom explored.

METHODS

In the study reported here, the incidence of AE was recorded in 92 patients with B-LPD (mostly chronic lymphocytic leukemia n  = 79) for whom ibrutinib alone was proposed as fist line therapy. Moreover, a pharmacokinetics (PK) exploration was planned over one day after 1 month treatment. PK assays included drug and metabolite (DHD-ibrutinib) mean/median and maximal plasmatic concentrations as well as areas under the curve (AUE) data.

RESULTS

This PK evaluation was analyzed regarding AEs recorded over the first year of therapy, which were similar as in published reports. PK data disclosed a significant impact of ibrutinib exposure on infections but mostly on the occurrence of hypertension. The latter was mostly related to dihydrodiol-ibrutinib (DHD-ibrutinib) exposure.

CONCLUSIONS

These data suggest that a DHD-ibrutinib assay after one month of treatment could be interesting to consider a lower dosage for patients above maximal concentration thresholds for the drug, its metabolite or the sum of both. Whether this can be applied to newer BTKi remains to be explored but it could be important for patients to whom ibrutinib is proposed.

Cardiovascular Considerations After Cancer Therapy: Gaps in Evidence and JACC: CardioOncology Expert Panel Recommendations

Cancer survivors, particularly those treated with anthracyclines and chest radiation, face an elevated risk of cancer therapy-related cardiovascular toxicity. These complications affect not only physical health, but also life expectancy. Risk factors for cancer therapy-related cardiovascular toxicity include age at which cancer treatment was received, the use of (potentially) cardiotoxic cancer therapies, and the presence of concomitant cardiovascular risk factors. Current guidelines provide recommendations for cardiovascular surveillance after cancer therapy, including type and frequency. All cancer survivors are advised to undergo annual clinical screenings and optimization of cardiovascular risk factors. Those at higher risk should undergo additional cardiovascular testing. This document aims to summarize the available evidence, present practical recommendations, and outline existent gaps in the current literature regarding cardiovascular care after cancer therapies.

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.

Bruton's tyrosine kinase inhibition suppresses pathological retinal angiogenesis

BACKGROUND AND PURPOSE

Pathological retinal angiogenesis is a typical manifestation of vision-threatening ocular diseases. Many patients exhibit poor response or resistance to anti-vascular endothelial growth factor (VEGF) agents. Bruton's tyrosine kinase (BTK) controls the proliferation and function of immune cells. Therefore, we examined the anti-inflammatory and anti-angiogenic effects of BTK inhibition on retinal angiogenesis.

EXPERIMENTAL APPROACH

Retinal neovascularisation and vascular leakage in oxygen-induced retinopathy in C57/BL6J mice were assessed by whole-mount retinal immunofluorescence. PLX5622 was used to deplete microglia and Rag1-knockout mice were used to test the contribution of lymphocytes to the effects of BTK inhibition. The cytokines, activation markers, inflammatory and immune-regulatory activities of retinal microglia/macrophages were detected using qRT-PCR and immunofluorescence. NLRP3 was detected by western blotting, and the effects of BTK inhibition on the co-culture of microglia and human retinal microvascular endothelial cells (HRMECs) were examined.

KEY RESULTS

BTK inhibition suppressed pathological angiogenesis and vascular leakage, and significantly reduced retinal inflammation, which involved microglia/macrophages but not lymphocytes. BTK inhibition increased anti-inflammatory factors and reduced pro-inflammatory cytokines that resulted from NLRP3 inflammasome activation. BTK inhibition suppressed the inflammatory activity of microglia/macrophages, and acted synergistically with anti-VEGF without retinal toxicity. Moreover, the supernatant of microglia incubated with BTK-inhibitor reduced the proliferation, tube formation and sprouting of HRMECs.

CONCLUSION AND IMPLICATIONS

BTK inhibition suppressed retinal neovascularisation and vascular leakage by modulating the inflammatory activity of microglia and macrophages. Our study suggests BTK inhibition as a novel and promising approach for alleviating pathological retinal angiogenesis.

Evaluation of bleeding risk in patients who received pirtobrutinib in the presence or absence of antithrombotic therapy

Clinical bleeding events are reported here from 773 patients with B-cell malignancies receiving pirtobrutinib monotherapy from the phase 1/2 BRUIN study (ClinicalTrials.gov identifier: NCT03740529), either in the presence or absence of antithrombotic therapy (antithrombotic exposed [AT-E], n = 216; antithrombotic nonexposed [AT-NE], n = 557). Among the AT-E cohort, 51.9% received platelet aggregation inhibitors, 36.6% received direct factor Xa inhibitors, 18.5% received heparins, 5.6% received salicylic acid for indications other than platelet aggregation inhibition, and 2.3% received thrombolytics. Warfarin was not permitted. Any-grade bleeding/bruising events occurred in 97 patients (44.9%; 95% confidence interval [CI], 38.3-51.5) in the AT-E cohort and 181 patients (32.5%; 95% CI, 28.6-36.4) in the AT-NE cohort. Most bleeding/bruising events in both cohorts began within the first 6 months of treatment (AT-E: 65.4%; AT-NE: 72.5%). Contusion was the most common bleeding/bruising event in both cohorts (AT-E: 22.7%; AT-NE: 18.1%). Grade ≥3 bleeding/bruising events were reported in six patients (2.8%) in the AT-E cohort and 11 patients (2.0%) in the AT-NE cohort. Bleeding/bruising events requiring or prolonging hospitalization were reported in 2.3% and 1.6% of patients in the AT-E and AT-NE cohorts, respectively. No bleeding/bruising events led to pirtobrutinib dose reduction or permanent discontinuation in the AT-E cohort, and one patient (0.2%) in the AT-NE cohort experienced an event requiring dose reduction. These data support the safety of pirtobrutinib in patients requiring antithrombotic therapies.

Cardiovascular events reported in patients with B-cell malignancies treated with zanubrutinib

ABSTRACT

First-generation Bruton tyrosine kinase (BTK) inhibitor, ibrutinib, has been associated with an increased risk of cardiovascular toxicities. Zanubrutinib is a more selective, next-generation BTK inhibitor. In this analysis, incidence rates of atrial fibrillation, symptomatic (grade ≥2) ventricular arrhythmia, and hypertension were evaluated in a pooled analysis of 10 clinical studies with zanubrutinib monotherapy in patients (N = 1550) with B-cell malignancies and a pooled analysis of head-to-head studies comparing zanubrutinib with ibrutinib (ASPEN cohort 1; ALPINE). Among the 10 studies, most patients (median age, 67 years) were male (66.3%) and had CLL/SLL (60.5%). Overall incidence and exposure-adjusted incidence rates (EAIR) for atrial fibrillation, symptomatic ventricular arrhythmia, and hypertension were lower with zanubrutinib than ibrutinib. Despite a similar prevalence of preexisting cardiovascular events in ASPEN and ALPINE, atrial fibrillation/flutter incidence rates (6.1% vs 15.6%) and EAIR (0.2 vs 0.64 persons per 100 person-months; P < .0001) were lower with zanubrutinib than with ibrutinib. Symptomatic ventricular arrhythmia incidence was low for both zanubrutinib (0.7%) and ibrutinib (1.7%) with numerically lower EAIR (0.02 vs 0.06 persons per 100 person-months, respectively) for zanubrutinib. The hypertension EAIR was lower with zanubrutinib than ibrutinib in ASPEN but similar between treatment arms in ALPINE. The higher hypertension EAIR in ALPINE was inconsistent with other zanubrutinib studies. However, fewer discontinuations (1 vs 14) and deaths (0 vs 6) due to cardiac disorders occurred with zanubrutinib versus ibrutinib in ALPINE. These data support zanubrutinib as a treatment option with improved cardiovascular tolerability compared with ibrutinib for patients with B-cell malignancies in need of BTK inhibitors. These trials were registered at www.ClinicalTrials.gov as # NCT03053440, NCT03336333, NCT03734016, NCT04170283, NCT03206918, NCT03206970, NCT03332173, NCT03846427, NCT02343120, and NCT03189524.

Diagnosis and Management of Cardiovascular Effects of Bruton's Tyrosine Kinase Inhibitors

PURPOSE OF REVIEW

Bruton's tyrosine kinase inhibitors (BTKis) have changed the treatment and prognosis of several B-cell malignancies. However, since the approval of the first BTKi, ibrutinib, reports of cardiovascular adverse events especially atrial fibrillation have arisen. In this review, we discuss the cardiovascular side effects of BTKis and the management of these toxicities in clinical practice.

RECENT FINDINGS

BTKIs increase the risks of atrial fibrillation, bleeding, hypertension, heart failure, and potentially ventricular arrhythmia. Newer second and third-generation BTKis appear to have a lower risk of cardiovascular adverse events; however, long-term follow-up data are not available for these new BTKis. BTKis are an effective treatment for some B-cell malignancies; however, they can cause cardiovascular side effects. The best preventive strategies to minimize cardiovascular complications remain undefined. Currently, a practical approach for managing patients receiving BTKis includes the management of cardiovascular risk factors and side effects of BTKis to prevent interruption of cancer treatment.

Serine/threonine-protein kinase STK24 induces tumorigenesis by regulating the STAT3/VEGFA signaling pathway

Lung cancer is the most common cause of cancer-related death. Although anti-angiogenesis therapy has been effective in the treatment of nonsmall cell lung cancer (NSCLC), drug-resistance is a common challenge. Therefore, there is a need to develop new therapeutic strategies for NSCLC. Serine/threonine-protein kinase 24 (STK24), also known as MST3, belongs to the germinal center kinase III subfamily, and the biological function of STK24 in NSCLC tumorigenesis and tumor angiogenesis is still unclear. In this study, we demonstrated that STK24 was overexpressed in lung cancer tissues compared with normal lung tissues, and lung cancer patients with higher STK24 expression levels had shorter overall survival time. In addition, our in vitro assays using A549 and H226 cell lines revealed that the STK24 expression level of cancer cells was positively correlated with cancer cells proliferation, migration, invasion, and tumor angiogenesis ability; in vivo assays also demonstrated that silencing of STK24 dramatically inhibited tumor progress and tumor angiogenesis. To investigate a mechanism, we revealed that STK24 positively regulated the signal transducer and activator of transcription 3 (STAT3)/vascular endothelial growth factor A (VEGFA) signaling pathway by inhibiting polyubiquitin-proteasomal-mediated degradation of STAT3. Furthermore, we performed in vivo assays in BALB/c nude mice and in vitro assays to show that STK24-regulated tumor angiogenesis depends on STAT3. These findings deepened our understanding of tumor angiogenesis, and the STK24/STAT3/VEGFA signaling pathway might be a novel therapeutic target for NSCLC treatment.

How we approach the perioperative management of patients with chronic lymphocytic leukaemia receiving continuous cancer-directed therapies

Historically, invasive procedures and surgeries were deferred in patients with haematological malignancies including advanced stage chronic lymphocytic leukaemia (CLL) because of limited life expectancy. However, novel, and often continuous, treatments have markedly improved outcomes in CLL. Some patients may expect years of treatment response and disease control, overcoming the short life expectancy that deters interventionalists. Such patients now often undergo various invasive procedures including major surgery. To inform peri-operative management, we summarize the relevant side effects and drug interactions of continuous CLL therapies, highlight potential surgical risks, and provide recommendations on withholding specific CLL drugs around invasive procedures.

Advances in Multimodality Imaging in Cardio-Oncology: JACC State-of-the-Art Review

The population of patients with cancer is rapidly expanding, and the diagnosis and monitoring of cardiovascular complications greatly rely on imaging. Numerous advances in the field of cardio-oncology and imaging have occurred in recent years. This review presents updated and practical approaches for multimodality cardiovascular imaging in the cardio-oncology patient and provides recommendations for imaging to detect the myriad of adverse cardiovascular effects associated with antineoplastic therapy, such as cardiomyopathy, atherosclerosis, vascular toxicity, myocarditis, valve disease, and cardiac masses. Uniquely, we address the role of cardiovascular imaging in patients with pre-existing cardiomyopathy, pregnant patients, long-term survivors, and populations with limited resources. We also address future avenues of investigation and opportunities for artificial intelligence applications in cardio-oncology imaging. This review provides a uniform practical approach to cardiovascular imaging for patients with cancer.

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.

Fixed-Duration Ibrutinib-Venetoclax in Patients with Chronic Lymphocytic Leukemia and Comorbidities

BACKGROUND: GLOW is a phase 3 trial evaluating the efficacy and safety of ibrutinib-venetoclax in older patients and/or those with comorbidities with previously untreated chronic lymphocytic leukemia (CLL). METHODS: We randomly assigned (1:1) patients 65 years of age or older or those 18 to 64 years of age who also had a Cumulative Illness Rating Scale (CIRS) score greater than 6 (CIRS scores range from 0 to 56, with higher scores indicating more impaired function of organ systems) or creatinine clearance of less than 70 ml/min, to ibrutinib-venetoclax (3 cycles ibrutinib lead-in, then 12 cycles ibrutinib-venetoclax) or chlorambucil-obinutuzumab (6 cycles). The primary end point was progression-free survival (PFS) assessed by an independent review committee. Secondary end points included undetectable minimal residual disease (uMRD), response rates, and safety. RESULTS: This study enrolled 211 patients, with 106 randomly assigned to ibrutinib-venetoclax and 105 to chlorambucil-obinutuzumab. With a median follow-up of 27.7 months, there were 22 PFS events for ibrutinib-venetoclax and 67 events for chlorambucil-obinutuzumab. PFS was significantly longer for ibrutinib-venetoclax than for chlorambucil-obinutuzumab (hazard ratio, 0.216; 95% confidence interval [CI], 0.131 to 0.357; P<0.001). The improvement in PFS with ibrutinib-venetoclax was consistent across predefined subgroups, including patients 65 years of age or older or with a CIRS score greater than 6. The best uMRD rate in bone marrow by next-generation sequencing was significantly higher for ibrutinib-venetoclax (55.7%) than for chlorambucil-obinutuzumab (21.0%; P<0.001). The proportion of patients with sustained uMRD in peripheral blood from 3 to 12 months after end of treatment was 84.5% for ibrutinib-venetoclax and 29.3% for chlorambucil-obinutuzumab. Four patients treated with ibrutinib-venetoclax required subsequent therapy compared with 27 patients receiving chlorambucil-obinutuzumab (hazard ratio, 0.143; 95% CI, 0.050 to 0.410). Adverse events grade 3 or greater occurred for 80 (75.5%) and 73 (69.5%) patients receiving ibrutinib-venetoclax and chlorambucil-obinutuzumab, respectively, with neutropenia being most common in both arms (37 [34.9%] and 52 [49.5%]). There were 11 (10.4%) and 12 (11.4%) all-cause deaths in the ibrutinib-venetoclax and chlorambucil-obinutuzumab arms, respectively. CONCLUSIONS: Ibrutinib-venetoclax, an all-oral, once-daily, fixed-duration combination, demonstrated superior PFS and deeper and better sustained responses versus chlorambucil-obinutuzumab as first-line CLL treatment in older patients and/or those with comorbidities. (Funded by Janssen Research & Development, LLC, and Pharmacyclics; ClinicalTrials.gov number, NCT03462719.)