The US Food and Drug Administration will now require Covid-19 vaccines from Pfizer/BioNTech and Moderna to use expanded warning labels with more information about the risk of a rare heart condition after vaccination.

The FDA plans to limit access to certain high-risk groups and also told Pfizer and Moderna to update their warning labels about heart inflammation.

Moderna said on Friday it had filed a marketing application for an updated COVID vaccine to the U.S. Food and Drug Administration.

The Food and Drug Administration says it has decided to continue approving COVID-19 vaccine updates for seniors and others at higher risk of severe disease, but will require vaccine makers to conduct major new clinical trials before approving them for wider use.

The U.S. Food and Drug Administration on Tuesday said it plans to require new clinical trials for approval of annual COVID-19 boosters for healthy Americans under age 65, effectively limiting them to older adults and those at risk of developing severe illness.

The updated warnings highlight a rare risk of heart inflammation in teen boys and young men, CBS News reported. The warning applies to males ages 16 to 25 and is based on new data from FDA safety monitoring and a 2023 study. This includes both Pfizer's Comirnaty and Moderna's Spikevax vaccines.