RELEASE
ARTICLE
The FDA has required the manufacturers of the mRNA COVID-19 vaccines Comirnaty (Pfizer-BioNTech) and Spikevax (Moderna) to revise their labels to include updated information about the risks of myocarditis/pericarditis.
The revised labels state that the risks of myocarditis and pericarditis, with onset of symptoms typically in the first week following vaccination, are highest in males 12-24 years old.1
The FDA has also required the addition of new cardiovascular safety information based on the estimated incidence of post-vaccination myocarditis and/or pericarditis and one longitudinal retrospective study in hospitalized patients 5-29 years old who were diagnosed with myocarditis following vaccination.
Based on health insurance claims data, the estimated incidence of myocarditis and/or pericarditis 1-7 days post-vaccination with the 2023-2024 formulations of the COVID-19 vaccines in persons 6 months to 64 years old was 8 cases/1 million doses; the incidence was highest in males 12-24 years old (27 cases/1 million doses).1
In the longitudinal retrospective study, at a median of about 5 months post-vaccination with either mRNA COVID-19 vaccine, persistence of abnormal cardiac MRI findings was common, but the clinical significance of these findings is unknown.2
- FDA approves required updated warning in labeling of mRNA COVID-19 vaccines regarding myocarditis and pericarditis following vaccination. June 25, 2025. Available at: https://bit.ly/4ljC1Jg. Accessed July 2, 2025.
- SS Jain et al. Cardiac manifestations and outcomes of COVID-19 vaccine-associated myocarditis in the young in the USA: longitudinal results from the Myocarditis After COVID Vaccination (MACiV) multicenter study. EClinicalMedicine 2024; 76:102809. doi:10.1016/j.eclinm.2024.102809