Disentangling a Thorny Issue: Myocarditis and Pericarditis Post COVID-19 and Following mRNA COVID-19 Vaccines

Safety and reactogenicity of the BNT162b2 COVID-19 vaccine: Development, post-marketing surveillance, and real-world data

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to urgent actions by innovators, vaccine developers, regulators, and other stakeholders to ensure public access to protective vaccines while maintaining regulatory agency standards. Although development timelines for vaccines against SARS-CoV-2 were much quicker than standard vaccine development timelines, regulatory requirements for efficacy and safety evaluations, including the volume and quality of data collected, were upheld. Rolling review processes supported by sponsors and regulatory authorities enabled rapid assessment of clinical data as well as emergency use authorization. Post-authorization and pharmacovigilance activities enabled the quantity and breadth of post-marketing safety information to quickly exceed that generated from clinical trials. This paper reviews safety and reactogenicity data for the BNT162 vaccine candidates, including BNT162b2 (Comirnaty, Pfizer/BioNTech COVID-19 vaccine) and bivalent variant-adapted BNT162b2 vaccines, from preclinical studies, clinical trials, post-marketing surveillance, and real-world studies, including an unprecedentedly large body of independent evidence.

COVID-19 Vaccination-Related Myocarditis: What We Learned From Our Experience and What We Need to Do in The Future

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 has led to a global health crisis with substantial mortality and morbidity. To combat the COVID-19 pandemic, various vaccines have been developed, but unexpected serious adverse events including vaccine-induced thrombotic thrombocytopenia, carditis, and thromboembolic events have been reported and became a huddle for COVID-19 vaccination. Vaccine-related myocarditis (VRM) is a rare but significant adverse event associated primarily with mRNA vaccines. This review explores the incidence, risk factors, clinical presentation, pathogenesis, management strategies, and outcomes associated with VRM. The incidence of VRM is notably higher in male adolescents and young adults, especially after the second dose of mRNA vaccines. The pathogenesis appears to involve an immune-mediated process, but the precise mechanism remains mostly unknown so far. Most studies have suggested that VRM is mild and self-limiting, and responds well to conventional treatment. However, a recent nationwide study in Korea warns that severe cases, including fulminant myocarditis or death, are not uncommon in patients with COVID-19 VRM. The long-term cardiovascular consequences of VRM have not been well understood and warrant further investigation. This review also briefly addresses the critical balance between the substantial benefits of COVID-19 vaccination and the rare risks of VRM in the coming endemic era. It emphasizes the need for continued surveillance, research to understand the underlying mechanisms, and strategies to mitigate risk. Filling these knowledge gaps would be vital to refining vaccination recommendations and improving patient care in the evolving COVID-19 pandemic landscape.

Responses to Common Misconceptions Relating to COVID-19 Variant-Adapted mRNA Vaccines

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the waning of immunity over time has necessitated the use of booster doses of original coronavirus disease 2019 (COVID-19) vaccines. This has also led to the development and implementation of variant-adapted messenger RNA (mRNA) vaccines that include an Omicron sub-lineage component in addition to the antigen based on the wild-type virus spike protein. Subsequent emergence of the recombinant XBB sub-lineages triggered the development of monovalent XBB-based variant-adapted mRNA vaccines, which are available for vaccination campaigns in late 2023. Misconceptions about new variant-adapted vaccines may exacerbate vaccine fatigue and drive the lack of vaccine acceptance. This article aims to address common concerns about the development and use of COVID-19 variant-adapted mRNA vaccines that have emerged as SARS-CoV-2 has continued to evolve.

COVID-19 Vaccines and Atrial Fibrillation: Analysis of the Post-Marketing Pharmacovigilance European Database

Atrial fibrillation (AF) has been described in COVID-19 patients. Recently, some case reports and US pharmacovigilance analyses described AF onset as a rare adverse event following COVID-19 vaccination. The possible correlation is unclear. We systematically analyzed the reports of AF related to COVID-19 vaccines collected in the European pharmacovigilance database, EudraVigilance (EV), from 2020 to November 2022. We carried out descriptive and disproportionality analyses. Moreover, we performed a sensitivity analysis, excluding the reports describing other possible alternative AF causes (pericarditis, myocarditis, COVID-19, or other drugs that may cause/exacerbate AF). Overall, we retrieved 6226 reports, which represented only 0.3% of all those related to COVID-19 vaccines collected in EV during our study period. AF reports mainly referred to adults (in particular, >65 years old), with an equal distribution in sex. Reports were mainly related to tozinameran (54.04%), elasomeran (28.3%), and ChAdOx1-S (14.32%). The reported AF required patient hospitalization in 35% of cases and resulted in a life-threatening condition in 10% of cases. The AF duration (when reported) was highly variable, but the majority of the events had a short duration (moda = 24 h). Although an increased frequency of AF reporting with mRNA vaccines emerges from our study, other investigations are required to investigate the possible correlation between COVID-19 vaccination and the rare AF occurrence.

COVID-19, Myocarditis and Pericarditis

Viral infections are a leading cause of myocarditis and pericarditis worldwide, conditions that frequently coexist. Myocarditis and pericarditis were some of the early comorbidities associated with SARS-CoV-2 infection and COVID-19. Many epidemiologic studies have been conducted since that time concluding that SARS-CoV-2 increased the incidence of myocarditis/pericarditis at least 15× over pre-COVID levels although the condition remains rare. The incidence of myocarditis pre-COVID was reported at 1 to 10 cases/100 000 individuals and with COVID ranging from 150 to 4000 cases/100 000 individuals. Before COVID-19, some vaccines were reported to cause myocarditis and pericarditis in rare cases, but the use of novel mRNA platforms led to a higher number of reported cases than with previous platforms providing new insight into potential pathogenic mechanisms. The incidence of COVID-19 vaccine-associated myocarditis/pericarditis covers a large range depending on the vaccine platform, age, and sex examined. Importantly, the findings highlight that myocarditis occurs predominantly in male patients aged 12 to 40 years regardless of whether the cause was due to a virus-like SARS-CoV-2 or associated with a vaccine-a demographic that has been reported before COVID-19. This review discusses findings from COVID-19 and COVID-19 vaccine-associated myocarditis and pericarditis considering the known symptoms, diagnosis, management, treatment, and pathogenesis of disease that has been gleaned from clinical research and animal models. Sex differences in the immune response to COVID-19 are discussed, and theories for how mRNA vaccines could lead to myocarditis/pericarditis are proposed. Additionally, gaps in our understanding that need further research are raised.

Soluble low density lipoprotein receptor-related protein-1 levels in the differential diagnosis of myopericarditis versus acute coronary syndrome

INTRODUCTION

Differential diagnosis of myopericarditis (MPC) versus acute coronary syndromes (ACS) can be difficult in the emergency room (ER). Low density lipoprotein receptor-related protein-1 (LRP-1) is a transmembrane receptor with diverse biological functions. LRP-1 is increased after viral infections as a defense mechanism. sLRP-1 (soluble form) can be measured in the serum. We study the diagnostic sLRP-1 levels in patients with MPC, ACS and healthy controls.

METHODS

The study included consecutive patients who were admitted between the dates of 1.1.2018 and 1.1.2019 with the diagnosis of MPC or ACS. All patients reported to the ER with chest pain (CP) and elevated cardiac troponin levels. Control group (n = 61) was selected from healthy subjects. In addition to routine laboratory work up, serum sLRP-1 concentrations were measured on admission.

RESULTS

sLRP-1 levels were significantly higher in MPC, compared to controls (p = 0.005) and ACS (p = 0.001). Median (IQR) sLRP-1 levels in MPC, controls and ACS were 7.39 (22.42), 2.27 (1.74), 2.41 (0.98) μg/ml, respectively (p = 0.004). Among the covariates: sLRP-1, age, gender, HDL-C and LDL-C; only sLRP-1 differentiated a diagnosis of MPC versus ACS (OR = 1684, p = 0,046, CI for OR (1008-2812). The area under the curve (AUC) was measured as 0.79 [CI 0.62-0.95] in ROC analysis, p = 0.001; sLRP-1 had 69% sensitivity and 85% specificity for diagnosis of MPC with a cut-off value of 4.3 μg/ml.

CONCLUSION

sLRP-1 is a potential biomarker in the differential diagnosis of MPC versus ACS in ER. Future studies are needed to evaluate and develop the utility of sLRP-1 as a diagnostic and prognostic biomarker in MPC.