FDA Delays Moderna Vaccine for Adolescents to Review Rare Side Effect

The FDA is delaying a decision on authorizing the Moderna vaccine for adolescents to deeper assess whether it may lead to heightened risk of a rare inflammatory heart condition.

The FDA has been taking another look at the risk of the condition, known as myocarditis, among young men who got the Moderna vaccine compared with those who got the Pfizer vaccine, the Wall Street Journal reports.

The FDA hasn’t determined whether there is a high risk yet, people familiar with the matter said. The delay could take several weeks. Indeed, the agency plans to review the data further before deciding whether to extend vaccine eligibility to younger age groups.

Moderna Chief Medical Officer Paul Burton said the FDA’s data on vaccines among 18-to-25-year-olds doesn’t show any significant difference in the rate of myocarditis among people who got the Moderna or Pfizer vaccines.

“I think people can be reassured that the risk of myocarditis with an mRNA vaccine is low, it appears to be balanced between the different products,” he said.