Tocilizumab in the treatment of myocardial infarction

Interleukin-receptor antagonist and tumour necrosis factor inhibitors for the primary and secondary prevention of atherosclerotic cardiovascular diseases

BACKGROUND

Atherosclerotic cardiovascular disease (ACVD) is worsened by chronic inflammatory diseases. Interleukin receptor antagonists (IL-RAs) and tumour necrosis factor-alpha (TNF) inhibitors have been studied to see if they can prevent cardiovascular events.

OBJECTIVES

The purpose of this study was to assess the clinical benefits and harms of IL-RAs and TNF inhibitors in the primary and secondary prevention of ACVD.

SEARCH METHODS

The Cochrane Heart Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase, EBSCO CINAHL plus, and clinical trial registries for ongoing and unpublished studies were searched in February 2024. The reference lists of relevant studies, reviews, meta-analyses and health technology reports were searched to identify additional studies. No limitations on language, date of publication or study type were set.

SELECTION CRITERIA

RCTs that recruited people with and without pre-existing ACVD, comparing IL-RAs or TNF inhibitors versus placebo or usual care, were selected. The primary outcomes considered were all-cause mortality, myocardial infarction, unstable angina, and adverse events.

DATA COLLECTION AND ANALYSIS

Two or more review authors, working independently at each step, selected studies, extracted data, assessed the risk of bias and used GRADE to judge the certainty of evidence.

MAIN RESULTS

We included 58 RCTs (22,053 participants; 21,308 analysed), comparing medication efficacy with placebo or usual care. Thirty-four trials focused on primary prevention and 24 on secondary prevention. The interventions included IL-1 RAs (anakinra, canakinumab), IL-6 RA (tocilizumab), TNF-inhibitors (etanercept, infliximab) compared with placebo or usual care. The certainty of evidence was low to very low due to biases and imprecision; all trials had a high risk of bias. Primary prevention: IL-1 RAs The evidence is very uncertain about the effects of the intervention on all-cause mortality(RR 0.33, 95% CI 0.01 to 7.58, 1 trial), myocardial infarction (RR 0.71, 95% CI 0.04 to 12.48, I² = 39%, 2 trials), unstable angina (RR 0.24, 95% CI 0.03 to 2.11, I² = 0%, 2 trials), stroke (RR 2.42, 95% CI 0.12 to 50.15; 1 trial), adverse events (RR 0.85, 95% CI 0.59 to 1.22, I² = 54%, 3 trials), or infection (rate ratio 0.84, 95% 0.55 to 1.29, I² = 0%, 4 trials). Evidence is very uncertain about whether anakinra and cankinumab may reduce heart failure (RR 0.21, 95% CI 0.05 to 0.94, I² = 0%, 3 trials). Peripheral vascular disease (PVD) was not reported as an outcome. IL-6 RAs The evidence is very uncertain about the effects of the intervention on all-cause mortality (RR 0.68, 95% CI 0.12 to 3.74, I² = 30%, 3 trials), myocardial infarction (RR 0.27, 95% CI 0.04 to1.68, I² = 0%, 3 trials), heart failure (RR 1.02, 95% CI 0.11 to 9.63, I² = 0%, 2 trials), PVD (RR 2.94, 95% CI 0.12 to 71.47, 1 trial), stroke (RR 0.34, 95% CI 0.01 to 8.14, 1 trial), or any infection (rate ratio 1.10, 95% CI: 0.88 to 1.37, I2 = 18%, 5 trials). Adverse events may increase (RR 1.13, 95% CI 1.04 to 1.23, I² = 33%, 5 trials). No trial assessed unstable angina. TNF inhibitors The evidence is very uncertain about the effects of the intervention on all-cause mortality (RR 1.78, 95% CI 0.63 to 4.99, I² = 10%, 3 trials), myocardial infarction (RR 2.61, 95% CI 0.11 to 62.26, 1 trial), stroke (RR 0.46, 95% CI 0.08 to 2.80, I² = 0%; 3 trials), heart failure (RR 0.85, 95% CI 0.06 to 12.76, 1 trial). Adverse events may increase (RR 1.13, 95% CI 1.01 to 1.25, I² = 51%, 13 trials). No trial assessed unstable angina or PVD. Secondary prevention: IL-1 RAs The evidence is very uncertain about the effects of the intervention on all-cause mortality (RR 0.94, 95% CI 0.84 to 1.06, I² = 0%, 8 trials), unstable angina (RR 0.88, 95% CI 0.65 to 1.19, I² = 0%, 3 trials), PVD (RR 0.85, 95% CI 0.19 to 3.73, I² = 38%, 3 trials), stroke (RR 0.94, 95% CI 0.74 to 1.2, I² = 0%; 7 trials), heart failure (RR 0.91, 95% 0.5 to 1.65, I² = 0%; 7 trials), or adverse events (RR 0.92, 95% CI 0.78 to 1.09, I² = 3%, 4 trials). There may be little to no difference between the groups in myocardial infarction (RR 0.88, 95% CI 0.0.75 to 1.04, I² = 0%, 6 trials). IL6-RAs The evidence is very uncertain about the effects of the intervention on all-cause mortality (RR 1.09, 95% CI 0.61 to 1.96, I² = 0%, 2 trials), myocardial infarction (RR 0.46, 95% CI 0.07 to 3.04, I² = 45%, 3 trials), unstable angina (RR 0.33, 95% CI 0.01 to 8.02, 1 trial), stroke (RR 1.03, 95% CI 0.07 to 16.25, 1 trial), adverse events (RR 0.89, 95% CI 0.76 to 1.05, I² = 0%, 2 trials), or any infection (rate ratio 0.66, 95% CI 0.32 to 1.36, I² = 0%, 4 trials). No trial assessed PVD or heart failure. TNF inhibitors The evidence is very uncertain about the effect of the intervention on all-cause mortality (RR 1.16, 95% CI 0.69 to 1.95, I² = 47%, 5 trials), heart failure (RR 0.92, 95% 0.75 to 1.14, I² = 0%, 4 trials), or adverse events (RR 1.15, 95% CI 0.84 to 1.56, I² = 32%, 2 trials). No trial assessed myocardial infarction, unstable angina, PVD or stroke. Adverse events may be underestimated and benefits inflated due to inadequate reporting.

AUTHORS' CONCLUSIONS

This Cochrane review assessed the benefits and harms of using interleukin-receptor antagonists and tumour necrosis factor inhibitors for primary and secondary prevention of atherosclerotic diseases compared with placebo or usual care. However, the evidence for the predetermined outcomes was deemed low or very low certainty, so there is still a need to determine whether these interventions provide clinical benefits or cause harm from this perspective. In summary, the different biases and imprecision in the included studies limit their external validity and represent a limitation to determining the effectiveness of the intervention for both primary and secondary prevention of ACVD.

Meta-analysis reveals inhibition of the inflammatory cytokine IL-6 affords limited protection post-myocardial ischemia/infarction

Background

Proinflammatory cytokine cascades play crucial roles in the onset and progression of myocardial ischemia and infarction. Clinically, elevated serum levels of pro-inflammatory cytokine interleukin-6 is a poor prognostic indicator for future cardiac events and cardiac morbidity. Despite several reports, there is no clear evidence of cardiac benefits of inhibiting IL-6 in pre-clinical and clinical settings.

Objective

To analyze the available data systematically and perform a meta-analysis to show the evidence of effects of IL-6 inhibition on cardiac remodeling and mortality in ischemic animal models.

Methods

We used PICO framework and the quality of the studies was assessed using SYRCLE's risk of bias tool. Studies with interventions i.e., genetic deletion or pharmacological inhibition of IL-6/IL-6R were included for the meta-analysis. Systematic review was synthesized by including pre-clinical as well as randomized clinical trials involving myocardial infarction patients treated with IL-6 inhibitors. The effect size of the pooled data was determined using standard mean difference and 95% confidence intervals.

Results

A total of 12 pre-clinical studies were included in the review for analysis. Most of the studies showed an unclear risk of bias as the selection and reporting criteria were poorly described. We observed high heterogeneity in the included studies due to the varying duration of myocardial infarction and the dosage of IL-6 antibodies used in the studies. Overall inhibition of IL-6 significantly increased area at risk [p = 0.001, SMD = 0.49 (95% CI: -0.36, 1.35)] and significantly reduced ejection fraction [p = 0.001, SMD = -0.19 (95% CI: -1.39, 1.01)] and end-diastolic diameter [p = 0.02, SMD = -0.25 (95% CI: -0.87, 0.36)] of left ventricle post-MI, but no effects on infarct size [p < 0.01, SMD = 0.00; 95% CI: -1.34, 0.58). In randomized clinical trials, the overall effect on C-reactive protein remains significantly unchanged on CRP levels (SMD = -0.38; 95% CI: -1.94, 0.55) post-treatment with IL-6R inhibitor tocilizumab. The meta-regression demonstrates a significant positive correlation (p = 0.058) between the increase in ischemic area and duration of ischemia post-surgery in the absence of IL-6. This meta-analysis indicates mixed effect of IL-6 inhibition on cardiac remodeling post-MI, particularly in protecting the myocardium viability from damaging acute inflammation but not significant on cardiac function of ischemic animal models.

Conclusion

Despite the well-established pro-inflammatory nature of IL-6 in myocardial ischemia, our meta-analysis reports a limited contribution of IL-6 in the cardiac remodeling of hearts in animal models of myocardial ischemia. Moreover, genetically deleted IL-6 murine models produced contrasting results. Additional pre-clinical studies exploring the pharmacological inhibition of IL-6R are required to determine the beneficial effects of IL-6 inhibitors in regulating cardiac remodeling. The findings from IL-6R inhibition have better clinical relevance compared to genetically inhibited IL-6.

Impact of Age on Systemic Inflammatory Profile of Patients With ST-Segment-Elevation Myocardial Infarction and Acute Ischemic Stroke

BACKGROUND

Aging is associated with a chronic low-grade inflammatory state. This condition may affect the acute inflammatory response involved in ST-segment-elevation myocardial infarction (STEMI) or acute ischemic stroke (AIS). We sought to compare the profile of a set of circulating inflammatory markers between young and older patients admitted for STEMI or AIS.

METHODS

HIBISCUS-STEMI (Cohort of Patients to Identify Biological and Imaging Markers of Cardiovascular Outcomes in ST Elevation Myocardial Infarction) and HIBISCUS-STROKE (Cohort of Patients to Identify Biological and Imaging Markers of Cardiovascular Outcomes in Stroke) are 2 cohort studies that enrolled patients with STEMI treated with primary percutaneous coronary intervention in the cardiac intensive care unit of Lyon and patients with AIS treated with mechanical thrombectomy in the Lyon Stroke Center, respectively from 2016 to 2019. Patients were classified as older if they were ≥65 years and as young if they were <65 years. In both cohorts, CRP (C-reactive protein), IL (interleukin)-6, IL-8, IL-10, MCP (monocyte chemoattractant protein), sTNF-RI (soluble tumor necrosis factor receptor I), sST2 (soluble form suppression of tumorigenicity 2), and VCAM-1 (vascular cellular adhesion molecule-1) were measured on serum collected at 5 time points using enzyme-linked immunosorbent assay. A multiple logistic regression model was performed to detect an association between area under the curve of circulating inflammatory markers within the first 48 hours and older age.

RESULTS

A total of 260 patients with STEMI and 164 patients with AIS were included. Of them, there were 76 (29%) and 105 (64%) older patients with STEMI and AIS, respectively. Following multivariable analysis, a high area under the curve of IL-6 and sTNF-RI, a low lymphocyte count, and a high neutrophil-lymphocyte ratio at 24 hours were associated with older age in patients with STEMI and AIS.

CONCLUSIONS

Older patients had higher IL-6 and sTFN-RI levels within the first 48 hours associated with a lower lymphocyte count and a higher neutrophil-lymphocyte ratio at 24 hours in both cohorts.

Inflammation and ischemic heart disease: The next therapeutic target?

Inflammation plays an important role in several stages of the cardiovascular continuum. In recent decades a plethora of studies have provided new data highlighting the role of inflammation in atherogenesis and atherothrombosis in two-way interactions with various cardiovascular risk factors and further influencing these dynamic processes. The concept of targeting residual inflammatory risk among individuals with ischemic heart disease (IHD) is therefore gaining increasing attention. Recently, several landmark randomized controlled trials have assessed different pharmacological approaches that may mitigate this residual risk. The results of some of these studies, such as CANTOS with canakinumab and COLCOT and LoDoCo2 with colchicine, are promising and have provided data to support this concept. Moreover, though several aspects remain to be clarified, these trials have shown the potential of modulating inflammation as a new target to reduce the risk of cardiovascular events in secondary prevention patients. In the present review, we aim to present a pragmatic overview of the complex interplay between inflammation and IHD, and to critically appraise the current evidence on this issue while presenting future perspectives on this topic of pivotal contemporary interest.

Inflammation and ischemic heart disease: The next therapeutic target?

Inflammation plays an important role in several stages of the cardiovascular continuum. In recent decades a plethora of studies have provided new data highlighting the role of inflammation in atherogenesis and atherothrombosis in two-way interactions with various cardiovascular risk factors and further influencing these dynamic processes. The concept of targeting residual inflammatory risk among individuals with ischemic heart disease (IHD) is therefore gaining increasing attention. Recently, several landmark randomized controlled trials have assessed different pharmacological approaches that may mitigate this residual risk. The results of some of these studies, such as CANTOS with canakinumab and COLCOT and LoDoCo2 with colchicine, are promising and have provided data to support this concept. Moreover, though several aspects remain to be clarified, these trials have shown the potential of modulating inflammation as a new target to reduce the risk of cardiovascular events in secondary prevention patients. In the present review, we aim to present a pragmatic overview of the complex interplay between inflammation and IHD, and to critically appraise the current evidence on this issue while presenting future perspectives on this topic of pivotal contemporary interest.

Biologics and their delivery systems: Trends in myocardial infarction

Cardiovascular disease is the leading cause of death around the world, in which myocardial infarction (MI) is a precipitating event. However, current therapies do not adequately address the multiple dysregulated systems following MI. Consequently, recent studies have developed novel biologic delivery systems to more effectively address these maladies. This review utilizes a scientometric summary of the recent literature to identify trends among biologic delivery systems designed to treat MI. Emphasis is placed on sustained or targeted release of biologics (e.g. growth factors, nucleic acids, stem cells, chemokines) from common delivery systems (e.g. microparticles, nanocarriers, injectable hydrogels, implantable patches). We also evaluate biologic delivery system trends in the entire regenerative medicine field to identify emerging approaches that may translate to the treatment of MI. Future developments include immune system targeting through soluble factor or chemokine delivery, and the development of advanced delivery systems that facilitate the synergistic delivery of biologics.

The Immunomodulatory Signature of Extracellular Vesicles From Cardiosphere-Derived Cells: A Proteomic and miRNA Profiling

Experimental data demonstrated that the regenerative potential and immunomodulatory capacity of cardiosphere-derived cells (CDCs) is mediated by paracrine mechanisms. In this process, extracellular vesicles derived from CDCs (EV-CDCs) are key mediators of their therapeutic effect. Considering the future applicability of these vesicles in human diseases, an accurate preclinical-to-clinical translation is needed, as well as an exhaustive molecular characterization of animal-derived therapeutic products. Based on that, the main goal of this study was to perform a comprehensive characterization of proteins and miRNAs in extracellular vesicles from porcine CDCs as a clinically relevant animal model. The analysis was performed by identification and quantification of proteins and miRNA expression profiles. Our results revealed the presence of clusters of immune-related and cardiac-related molecular biomarkers in EV-CDCs. Additionally, considering that priming stem cells with inflammatory stimuli may increase the therapeutic potential of released vesicles, here we studied the dynamic changes that occur in the extracellular vesicles from IFNγ-primed CDCs. These analyses detected statistically significant changes in several miRNAs and proteins. Notably, the increase in interleukin 6 (IL6) protein, as well as the increase in mir-125b (that targets IL6 receptor) was especially relevant. These results suggest a potential involvement of EV-CDCs in the regulation of the IL6/IL6R axis, with implications in inflammatory-mediated diseases.