OUP accepted manuscript

Long-term cardiovascular outcomes of immune checkpoint inhibitor-related myocarditis: A large single-centre analysis

AIMS

Immune checkpoint inhibitors (ICI) are the cornerstone of modern oncology; however, side effects such as ICI-related myocarditis (irM) can be fatal. Recently, Bonaca proposed criteria for irM; however, it is unknown if they correlate well with cardiovascular (CV) ICI-related adverse events. Additionally, whether incident irM portends worse long-term CV outcomes remains unclear. We aimed to determine the incidence of long-term CV comorbidities and CV mortality among irM patients.

PATIENTS AND METHODS

The ICI-related adverse event (irAE) registry was queried to identify irM patients by using Bonaca criteria. Random controls were selected after excluding patients with other concomitant irAEs. Patients' demographics, comorbidities and myocarditis presenting features were gathered. Outcomes included 2-year freedom from CV comorbidities (composite of atrial fibrillation, stroke, myocardial infarction and heart failure) and freedom from CV death. IrM was treated as a time-varying covariate.

RESULTS

Seventy-six patients developed irM at a median of 167 days (mean age 69, 63.2% male, 47% lung cancer). Majority of patients had new wall motion abnormalities or EKG changes on presentation. Mean LVEF was 43%, median peak TnT was 0.81, and median NTproBNP was 2057 at irM onset. Two-year freedom from CV comorbidities (67% vs 86.8%, P < 0.001) and death (93.4% vs 99.3%, P = 0.003) was lower among irM patients. Incident irM was an independent predictor of CV death (HR 8.28, P = 0.048), but not CV comorbidities (HR 2.21, P = 0.080).

CONCLUSIONS

This is the largest case-control study on irM highlighting worse long-term CV outcomes. Future studies are needed to establish appropriate therapeutic strategies and efficient screening strategies for irM survivors.

Frequency and Consequences of Immune Checkpoint Inhibitor-Associated Inflammatory Changes in Different Organs: An Autopsy Study Over 13 -Years

Although immune checkpoint inhibitors (ICIs) have revolutionized modern oncology, they are also associated with immune-related adverse events (irAEs). Previous histopathologic descriptions of organ-related inflammatory changes do not consider systemic effects of ICIs, because of the absence of comprehensive autopsy studies. We performed a retrospective study on 42 whole-body autopsies of patients treated with ICIs from January 2011 to March 2024 to determine the frequency, organ distribution, and morphology of ICI-associated inflammatory changes as well as their clinical relevance. Twenty-three of 42 (54.8%) patients presented irAEs with inflammatory changes in at least one organ. Most frequent irAEs were ICI-related hypophysitis (N = 12; 28.6%), myocarditis (N = 8; 19.0%), pneumonitis (N = 5; 11.9%), hepatitis (N = 6; 14.3%), and adrenalitis (N = 5; 11.9%). ICI-related inflammation was mainly characterized by lymphohistiocytic and macrophage-rich tissue infiltrates, whereas a granulomatous "sarcoid-like" reaction was observed in 1 patient. Cause of death was attributable to ICI therapy in 7 (16.7%) patients, with ICI-associated myocarditis as the most common cause of death (N = 5; 71.4%). Clinically, irAEs were unsuspected in 5 of 7 ICI-related deaths (71.4%). Among irAEs, myocarditis has been clinically undiagnosed in 5 out of 8 cases (62.5%). Encephalitis was identified only at autopsy in all cases (N = 2). Hypophysitis was clinically unsuspected in 8 of 12 (66.7%) cases. Patients who died from irAEs developed more frequently a complete tumor regression than patients who died from other causes (P = .018). Of note, ICI-related myocarditis and pneumonitis were both associated with a systemic occurrence irAEs. Our study demonstrates that some irAEs, especially myocarditis, hypophysitis, and encephalitis, are clinically underdiagnosed. Autopsy remains a valuable tool to monitor diagnostic accuracy and therapeutic side effects in patients who died under ICI therapy.

Multimodality Imaging and Immune-Related Adverse Events During Immune Checkpoint Inhibitors Treatment: Where Do We Stand?

Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy, significantly improving survival across various malignancies. However, these therapies are associated with various types of immune-related adverse events (irAEs), including cardiotoxicity, a spectrum of rare but potentially life-threatening complications impacting significantly morbidity and mortality. Cardiovascular imaging has become key in cardio-oncology, providing essential diagnostic tools for early detection and monitoring. This review synthesizes current evidence and underlines the pivotal role of early and tailored imaging strategies in managing ICI-induced cardiotoxicity. By bridging the knowledge gap, it aims to provide targetable insights to optimize the clinical management in patients undergoing immunotherapy.

Immunotherapy-Related Adverse Events and Clinical Outcomes in Adult Solid-Tumor Patients Admitted to an Onco-Hospitalist Medicine Service

Background/Objectives: Few studies have focused on patients with immune-related adverse events (irAEs) after immune checkpoint inhibitor (ICI) treatment who were cared for primarily by hospitalists. The objective of our study was to describe the patterns and outcomes of adult solid-tumor cancer patients admitted to our onco-hospital medicine service. Methods: We retrospectively reviewed patients with solid tumors who received ICIs and were admitted to our service in 2021-2022 with an irAE and compared them to a control group (IOTOX vs. NO IOTOX, respectively). The primary outcome was the patterns of irAEs requiring hospitalization; secondary outcomes included 30-day emergency room visit, readmission, and 30-day mortality. Results: There were 144 patients in the IOTOX group and 286 controls. The most common tumor type was lung and thoracic malignancies (62, 43.1%). The most common ICI causing the irAEs was pembrolizumab (66, 45.8%). The most common irAEs were pneumonitis (49, 34%), colitis (28, 19.4%), hepatitis (18, 12.5%), and myocarditis (16, 11.1%). Of the 144 patients, eight (6%) died from the hospitalization irAE. Fifteen (15.6%) had an ER visit within 30 days due to the same irAE, and thirteen (13.7%) were readmitted. Survival at 30 days after discharge did not differ significantly between groups. Conclusions: Despite many patients having severe irAEs and irAEs associated with higher mortality, they generally had a favorable outcome compared to the literature.

Association among major adverse cardiovascular events with immune checkpoint inhibitors: A systematic review and meta-analysis

BACKGROUND

This meta-analysis aimed to determine the incidence and overall risk of major adverse cardiovascular events (MACEs) related to immune checkpoint inhibitors (ICIs).

METHODS

We systematically searched all cohort studies, including the available MACE data in cancer patients receiving ICIs, in PubMed, Embase, and the Cochrane Library, from their inception to September 5, 2023. The primary outcome was the incidence of MACEs associated with ICI exposure, and the secondary outcome was the overall risk of MACEs associated with ICI exposure versus non-ICI exposure controls. Risk ratios with 95% confidence intervals were used in the random- or fixed-effects models.

RESULTS

Overall, 26 cohort studies met the inclusion criteria, involving 109,883 cancer patients. In the median follow-up period ranging from 3.3 to 55.2 months, the incidence of MACEs associated with ICI exposure was 8.22%, ranging from 0.55% to 3.98%, among the nine MACEs, including myocarditis, tachyarrhythmia, pericarditis, pericardial effusions, cardiovascular death, myocardial infarction, heart failure, stroke, and conduction disorder. The incidence of MACE associated with non-ICI exposure was 3.84%, ranging from 0.81% to 4.72%. The risks of all-grade MACEs and pericardial effusions were significantly higher in the ICI group than in the non-ICI controls. ICI treatment, age, male sex, and prior radiation therapy were significantly associated with MACEs.

CONCLUSION

The risk of MACEs during ICI treatment in patients with cancer is more common than is currently recognized. ICI use is closely associated with an increased risk of MACEs. Patients at risk were older, male, and had a history of radiation therapy.

Close Cardiovascular Monitoring during the Early Stages of Treatment for Patients Receiving Immune Checkpoint Inhibitors

Background: There is an unmet medical need for the early detection of immune checkpoint inhibitor (ICI)-induced cardiovascular (CV) adverse events due to a lack of adequate biomarkers. This study aimed to provide insights on the incidence of troponin elevations and echocardiographic dynamics during ICI treatment in cancer patients and their role as potential biomarkers for submyocardial damage. In addition, it is the first study to compare hs-TnT and hs-TnI in ICI-treated patients and to evaluate their interchangeability in the context of screening. Results: Among 59 patients, the mean patient age was 68 years, and 76% were men. Overall, 25% of patients received combination therapy. Although 10.6% [95% CI: 5.0-22.5] of the patients developed troponin elevations, none experienced a CV event. No significant changes were found in 3D left ventricular (LV) ejection fraction nor in global longitudinal strain f (56 ± 6% vs. 56 ± 6%, p = 0.903 and -17.8% [-18.5; -14.2] vs. -17.0% [-18.8; -15.1], p = 0.663) at 3 months. There were also no significant changes in diastolic function and right ventricular function. In addition, there was poor agreement between hs-TnT and hs-TnI. Methods: Here, we present a preliminary analysis of the first 59 patients included in our ongoing prospective clinical trial (NCT05699915) during the first three months of treatment. All patients underwent electrocardiography and echocardiography along with blood sampling at standardized time intervals. This study aimed to investigate the incidence of elevated hs-TnT levels within the first three months of ICI treatment. Elevations were defined as hs-TnT above the upper limit of normal (ULN) if the baseline value was normal, or 1.5 ≥ times baseline if the baseline value was above the ULN. Conclusions: Hs-TnT elevations occurred in 10.6% of the patients. However, no significant changes were found on 3D echocardiography, nor did any of the patients develop a CV event. There were also no changes found in NT-proBNP. The study is still ongoing, but these preliminary findings do not show a promising role for cardiac troponins nor for echocardiographic dynamics in the prediction of CV events during the early stages of ICI treatment.

Immune checkpoints in cardiac physiology and pathology: therapeutic targets for heart failure

Immune checkpoint molecules are physiological regulators of the adaptive immune response. Immune checkpoint inhibitors (ICIs), such as monoclonal antibodies targeting programmed cell death protein 1 or cytotoxic T lymphocyte-associated protein 4, have revolutionized cancer treatment and their clinical use is increasing. However, ICIs can cause various immune-related adverse events, including acute and chronic cardiotoxicity. Of these cardiovascular complications, ICI-induced acute fulminant myocarditis is the most studied, although emerging clinical and preclinical data are uncovering the importance of other ICI-related chronic cardiovascular complications, such as accelerated atherosclerosis and non-myocarditis-related heart failure. These complications could be more difficult to diagnose, given that they might only be present alongside other comorbidities. The occurrence of these complications suggests a potential role of immune checkpoint molecules in maintaining cardiovascular homeostasis, and disruption of physiological immune checkpoint signalling might thus lead to cardiac pathologies, including heart failure. Although inflammation is a long-known contributor to the development of heart failure, the therapeutic targeting of pro-inflammatory pathways has not been successful thus far. The increasingly recognized role of immune checkpoint molecules in the failing heart highlights their potential use as immunotherapeutic targets for heart failure. In this Review, we summarize the available data on ICI-induced cardiac dysfunction and heart failure, and discuss how immune checkpoint signalling is altered in the failing heart. Furthermore, we describe how pharmacological targeting of immune checkpoints could be used to treat heart failure.

Reflecting on the cardiac toxicity in non-small cell lung cancer in the era of immune checkpoint inhibitors therapy combined with thoracic radiotherapy

In recent years, immune checkpoint inhibitors (ICIs) have become a widely used treatment for non-small cell lung cancer (NSCLC), and the combination with traditional radiotherapy (RT) has shown significant potential in prolonging patient survival. However, both thoracic RT and ICIs can lead to cardiac toxicity, including radiation-induced heart damage (RIHD) and immunotherapy-related heart damage (IRHD). It still remains uncertain whether the combination of thoracic RT and immunotherapy will exacerbate acute or late cardiovascular (CV) toxicity and incidence. In this review, we summarize safety data from relevant clinical studies regarding CV toxicity for the combination therapy in NSCLC patients, explore the underlying synergetic mechanisms and common risk factors, and proposed treatment and management strategies. We hope to increase emphasis on the long-term assessment of CV toxicity risks associated with the combination therapy, and reduce the incidence of CV deaths resulting from such regimens.

ANGPTL2 promotes immune checkpoint inhibitor-related murine autoimmune myocarditis

Use of immune checkpoint inhibitors (ICIs) as cancer immunotherapy advances rapidly in the clinic. Despite their therapeutic benefits, ICIs can cause clinically significant immune-related adverse events (irAEs), including myocarditis. However, the cellular and molecular mechanisms regulating irAE remain unclear. Here, we investigate the function of Angiopoietin-like protein 2 (ANGPTL2), a potential inflammatory mediator, in a mouse model of ICI-related autoimmune myocarditis. ANGPTL2 deficiency attenuates autoimmune inflammation in these mice, an outcome associated with decreased numbers of T cells and macrophages. We also show that cardiac fibroblasts express abundant ANGPTL2. Importantly, cardiac myofibroblast-derived ANGPTL2 enhances expression of chemoattractants via the NF-κB pathway, accelerating T cell recruitment into heart tissues. Our findings suggest an immunostimulatory function for ANGPTL2 in the context of ICI-related autoimmune inflammation and highlight the pathophysiological significance of ANGPTL2-mediated cardiac myofibroblast/immune cell crosstalk in enhancing autoimmune responses. These findings overall provide insight into mechanisms regulating irAEs.

Role of Biomarkers in the Management of Immune-Checkpoint Inhibitor-Related Myocarditis

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI)-related myocarditis poses a major clinical challenge given its non-specific presentation, rapid progression, and high mortality rate. Here, we review the role of blood-based biomarkers in the clinical management of patients with ICI-related myocarditis.

RECENT FINDINGS

Myocardial injury, its unique pattern, and the co-occurrence with myositis are defining features of ICI-related myocarditis. Non-cardiac biomarkers, specifically creatinine phosphokinase, precedes the symptomatic presentation and is highly sensitive for diagnosing ICI-related myocarditis, making them useful screening biomarkers. Combined elevations in cardiac troponins and non-cardiac biomarkers improve the confidence of an ICI myocarditis diagnosis. High troponin and creatinine phosphokinase levels are strongly associated with severe outcomes. We propose biomarker-based algorithms for the monitoring and diagnosis of ICI-related myocarditis. Biomarkers, such as cardiac troponins and creatine phosphokinase, can be used in combination in the monitoring, diagnosis, and prognostication of patients with ICI-related myocarditis.

Early evaluation of severe immune checkpoint inhibitor-associated myocarditis: a real-world clinical practice

PURPOSE

Immune checkpoint inhibitor (ICI)-associated myocarditis is a rare but severe complication for patients treated with immunotherapy. This study aims to explore the predictive significance of patients' clinical features and examination results for the severity of ICI-associated myocarditis.

METHODS

Data from a real-world cohort of 81 cancer patients who developed ICI-associated myocarditis after immunotherapy were retrospectively analyzed. The development of myocarditis of Common Terminology Criteria for Adverse Events (CTCAE) grades 3-5 and/or the major adverse cardiovascular event (MACE) was set as endpoints. Logistic regression was used to evaluate the predictive value of each factor.

RESULTS

CTCAE grades 3-5 and MACE developed in 43/81 (53.1%) and 28/81 (34.6%) cases, respectively. The likelihood of CTCAE grades 3-5 and MACE increased with the accumulation of organs affected by the ICI-associated adverse events and initial clinical symptoms. Concurrent systematic therapies during ICI treatment did not raise the risk of myocarditis severity, while prior chemotherapy did. Besides classical serum cardiac markers, a higher neutrophil ratio was also related to poorer cardiac outcomes, whereas higher lymphocyte and monocyte ratios were predictors of favorable cardiac outcomes. The CD4+ T cell ratio and CD4/CD8 ratio were negatively related to CTCAE grades 3-5. Several cardiovascular magnetic resonance parameters were associated with myocarditis severity, whereas the predictive value of echocardiography and electrocardiogram was weak.

CONCLUSION

This study comprehensively evaluated the prognostic value of patients' clinical characteristics and examination results and identified several predictors of severe ICI-associated myocarditis, which will facilitate early detection of severe ICI-associated myocarditis in patients receiving immunotherapy.

Multidisciplinary recommendations for essential baseline functional and laboratory tests to facilitate early diagnosis and management of immune-related adverse events among cancer patients

Immune checkpoint inhibitors (ICIs) have fundamentally changed the treatment landscape of various cancers. While ICI treatments result in improved survival, quality of life and are cost-effective, the majority of patients experience at least one immune-related adverse event (irAE). Many of these side effects cause little discomfort or are asymptomatic; however, irAEs can affect any organ and are potentially life-threatening. Consequently, early diagnosis and appropriate treatment of irAEs are critical for optimizing long-term outcomes and quality of life in affected patients. Some irAEs are diagnosed according to typical symptoms, others by abnormal findings from diagnostic tests. While there are various guidelines addressing the management of irAEs, recommendations for the early recognition of irAEs as well as the optimal extent and frequency of laboratory tests are mostly lacking. In clinical practice, blood sampling is usually performed before each ICI administration (i.e., every 2-3 weeks), often for several months, representing a burden for patients as well as health care systems. In this report, we propose essential laboratory and functional tests to improve the early detection and management of irAEs and in cancer patients treated with ICIs. These multidisciplinary expert recommendations regarding essential laboratory and functional tests can be used to identify possible irAEs at an early time point, initiate appropriate interventions to improve patient outcomes, and reduce the burden of blood sampling during ICI treatment.

Extensive CArdioVAscular Characterization and Follow-Up of Patients Receiving Immune Checkpoint Inhibitors: A Prospective Multicenter Study

BACKGROUND

The increasing use of immune checkpoint inhibitors (ICIs) in the treatment of both advanced and early stages of various malignancies has resulted in a substantial increase in the incidence of cardiovascular (CV) immune-related adverse events (irAEs). The current follow-up guidelines are based on anecdotal evidence and expert opinions, due to a lack of solid data and prospective studies. As many questions remain unanswered, cardiac monitoring, in patients receiving ICIs, is not always implemented by oncologists. Hence, an urgent need to investigate the possible short- and long-term CV effects of ICIs, as ICI approval is continuing to expand to the (neo)adjuvant setting.

METHODS

We have initiated a prospective, multicenter study, i.e., the CAVACI trial, in which a minimum of 276 patients with a solid tumor, eligible for ICI treatment, will be enrolled. The study consists of routine investigations of blood parameters (troponin and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, in particular) and a thorough CV follow-up (electrocardiograms, transthoracic echocardiograms, and coronary calcium scoring) at fixed time points for a total period of two years. The primary endpoint is the cumulative incidence of troponin elevation in the first three months of ICI treatment, compared to baseline levels. Furthermore, secondary endpoints include incidence above the upper limit of normal of both troponin and NT-proBNP levels, evolution in troponin and NT-proBNP levels, the incidence of CV abnormalities/major adverse cardiac events, evaluation of associations between patient characteristics/biochemical parameters and CV events, transthoracic echocardiography parameters, electrocardiography parameters, and progression of coronary atherosclerosis. Recruitment of patients started in January 2022. Enrolment is ongoing in AZ Maria Middelares, Antwerp University Hospital, AZ Sint-Vincentius Deinze, and AZ Sint-Elisabeth Zottegem.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05699915, registered 26 January 2023.

Predictive Biomarkers for Checkpoint Inhibitor Immune-Related Adverse Events

Immune-checkpoint inhibitors (ICIs) are antagonists of inhibitory receptors in the immune system, such as the cytotoxic T-lymphocyte-associated antigen-4, the programmed cell death protein-1 and its ligand PD-L1, and they are increasingly used in cancer treatment. By blocking certain suppressive pathways, ICIs promote T-cell activation and antitumor activity but may induce so-called immune-related adverse events (irAEs), which mimic traditional autoimmune disorders. With the approval of more ICIs, irAE prediction has become a key factor in improving patient survival and quality of life. Several biomarkers have been described as potential irAE predictors, some of them are already available for clinical use and others are under development; examples include circulating blood cell counts and ratios, T-cell expansion and diversification, cytokines, autoantibodies and autoantigens, serum and other biological fluid proteins, human leucocyte antigen genotypes, genetic variations and gene profiles, microRNAs, and the gastrointestinal microbiome. Nevertheless, it is difficult to generalize the application of irAE biomarkers based on the current evidence because most studies have been retrospective, time-limited and restricted to a specific type of cancer, irAE or ICI. Long-term prospective cohorts and real-life studies are needed to assess the predictive capacity of different potential irAE biomarkers, regardless of the ICI type, organ involved or cancer site.