FDA requires rare heart disease risk warning for COVID-19 vaccines.

FDA requires rare heart disease risk warning for COVID-19 vaccines.

The Food and Drug Administration (FDA) has mandated an updated warning regarding a rare heart side effect associated with COVID-19 vaccines. The new labeling, effective as of June 25, 2025, aims to provide more detailed information about the risk of myocarditis and pericarditis following administration of mRNA COVID-19 vaccines [2].

The FDA's decision follows a request sent in April to Pfizer and Moderna to update their vaccine labels. The new warning highlights the risk of myocarditis and pericarditis, particularly in males aged 12 to 24, with an estimated unadjusted incidence of approximately 8 cases per million doses in individuals aged 6 months to 64 years, and 27 cases per million doses in males aged 12 to 24 [2].

The updated warning also includes results from a study that collected information on cardiac magnetic resonance imaging (cardiac MRI) in people who developed myocarditis after receiving an mRNA COVID-19 vaccine. The study found that most patients had received a two-dose primary series of an mRNA COVID-19 vaccine prior to their diagnosis. At a median follow-up of approximately 5 months post-vaccination, persistence of abnormal cardiac MRI findings was common, although the clinical and prognostic significance of these findings is not yet known [2].

The FDA's move comes amid ongoing debates about the continuing use of COVID-19 vaccines for key groups, including pregnant women and children. The new advisory panel, appointed by Health Secretary Robert F. Kennedy Jr., has sparked controversy due to its anti-vaccine leanings [1]. The FDA's decision to update the vaccine labels is part of a broader effort by officials under Kennedy to restrict or undercut the use of vaccines.

While some experts argue that the new warning is a necessary step, others contend that it may cause unnecessary alarm. Dr. Robert Morris of the University of Washington stated, "They are right to suggest that we need to consider myocarditis risks associated with the vaccine, but what they propose is exactly the wrong solution. We should be investigating who is prone to myocarditis to see if we can predict and mitigate that risk" [1].

The FDA emphasizes that continuous monitoring and assessment of vaccine safety remain a priority. Manufacturers are required to conduct studies to assess long-term heart effects in people who have had myocarditis after receiving an mRNA COVID-19 vaccine [2].

References:
[1] https://www.barchart.com/story/news/33054552/fda-requires-updated-warning-about-rare-heart-risk-with-covid-shots
[2] https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/fda-approves-required-updated-warning-labeling-mrna-covid-19-vaccines-regarding-myocarditis-and