The promise of mRNA technology seemed boundless after the success of the coronavirus vaccines, but Robert F. Kennedy Jr. has singled it out for scrutiny, clouding its prospects.

Among the eight people Robert F. Kennedy Jr. announced would make up his new group of outside vaccine advisers to the US Centers for Disease Control and Prevention are an emergency physician who posted Islamophobic commentary on social media and two doctors who were paid to provide expert testimony in trials against a vaccine maker.

The safety of approved mRNA vaccines is well-established and, as with other vaccines, continues to be monitored by multiple surveillance systems.

The FDA's approval was based on a study of 11,400 people age 12 and older that compared the new low-dose vaccine with Moderna's existing vaccine. It found the new vaccine was safe and was at least as effective - and more by some measures - than the original shot, the company said.

Moderna, over the weekend, announced that the U.S. Food and Drug Administration had approved its second-generation COVID vaccine, but only for specific populations: all adults 65 and over and those between 12 and 64 with at least one underlying risk factor as defined by the Centers for Disease Control and Prevention.

The Food and Drug Administration has approved Moderna's new COVID-19 vaccine, days after the federal government tightened vaccine standards for the virus.

RFK dismissed the CDC's scientific vaccine advisers. His appointees for replacements are raising concerns about vaccine policy and recommendations moving forward.

Moderna's mNexspike COVID vaccine approved by FDA for older adults and at-risk groups after Phase 3 trial shows improved efficacy and safety profile.

Three of the health secretary’s picks to replace fired members of an influential panel that sets U.S. vaccine policies have filed statements in court flagging concerns about vaccines.