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FDA asks mRNA vaccine makers to widen age range for rare heart risk warning
Letters to Moderna and Pfizer/BioNTech follow tighter booster framework
In another sign of growing scrutiny over Covid-19 vaccines, the Food and Drug Administration has asked the two makers of mRNA vaccines to widen the age range of boys and young men that their labels say are at risk for a rare side effect causing heart inflammation.
The letters, first reported by CBS News, asked Moderna and partners Pfizer and BioNTech to make updates to safety information based on new studies of myocarditis or pericarditis or both after vaccination. Both reactions are rare and known to occur most often in young men within a week after the second shot in the two-dose Covid-19 vaccine regimen, according to the Centers for Disease Control and Prevention. Most cases were mild, causing no more than brief chest pain.
