FDA Requests Label Updates on COVID-19 Vaccine Heart Risks

FDA Demands Updated Myocarditis Warnings from Pfizer/BioNTech and Moderna

The U.S. Food and Drug Administration (FDA) has formally requested that Pfizer/BioNTech and Moderna revise the labeling of their COVID-19 vaccines to more accurately reflect the risks of cardiovascular complications, specifically myocarditis and pericarditis. In letters sent to both companies on April 17, and subsequently made public on May 21, the FDA highlighted "the persistence of abnormal cardiac magnetic resonance imaging findings that are a marker for myocardial injury" in recipients of the vaccines.

These imaging abnormalities, together with previously reported cases of myocarditis and pericarditis, represent "new safety information" according to the agency, which must be incorporated into the vaccine labels. Pfizer/BioNTech and Moderna were given a deadline of May 17 to propose label changes or contest the FDA’s directive.

Current Warnings and Proposed Label Refinements

Both COVID-19 vaccines already include myocarditis and pericarditis warnings, but the FDA is seeking more precise language on the age groups at greatest risk. The current Pfizer/BioNTech Comirnaty label states that the risk is "highest in males 12 through 17 years of age," while Moderna’s Spikevax label notes the highest risk in "males 18 through 24 years of age." The FDA is requesting that both labels specify the age range as "males 16 through 25 years of age" to better reflect epidemiological data.

Myocarditis and pericarditis—conditions involving inflammation of the heart muscle and its lining, respectively—have been recognized side effects of mRNA COVID-19 vaccines since their initial rollout.

Context: FDA’s Broader COVID-19 Vaccine Strategy and Public Trust Concerns

This label update request emerges amid significant shifts in COVID-19 vaccine policy under the current U.S. administration. On May 20, the FDA introduced a new risk-based framework prioritizing vaccine approvals and recommendations for seniors aged 65 and older and high-risk individuals aged six months to 64 years. These populations are considered more vulnerable due to underlying conditions such as obesity, mental health disorders, and cardiovascular risks.

At a recent town hall, Vinay Prasad, director of the FDA’s Center for Biologics Evaluation and Research, addressed the issue of public skepticism toward ongoing booster recommendations. He criticized the repeated booster campaigns for "average-risk, low-risk Americans," stating the lack of "gold standard science" supporting these measures.

Additionally, the FDA approved Novavax’s COVID-19 vaccine, Nuvaxovid, after a six-week delay. The approval follows the new guidelines, limiting its indication to adults 65 and older and individuals 12 to 64 years old with at least one underlying high-risk condition for severe COVID-19 outcomes.

Highlights

• The FDA requested Pfizer/BioNTech and Moderna update vaccine labels to better describe myocarditis/pericarditis risks.
• Both companies must respond by May 17 with proposed changes or objections.
• FDA wants the myocarditis risk age range unified to males 16-25 years.
• Myocarditis and pericarditis remain acknowledged side effects of mRNA COVID-19 vaccines.
• New FDA risk-based framework focuses on older adults and high-risk individuals.
• FDA highlights public distrust caused by ongoing booster recommendations for low-risk groups.
• Novavax’s vaccine recently approved with restrictions targeting older adults and high-risk individuals.