CHENNAI: The US Food and Drug Administration (FDA) on Saturday officially approved Moderna’s next-generation COVID-19 vaccine for use in key high-risk populations. This marks the first FDA endorsement of a COVID-19 vaccine since the agency revised its regulatory guidelines to tighten standards for safety and efficacy reviews.

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.

The FDA has approved Moderna’s new Covid-19 vaccine, though it placed restrictions on its use that the company’s existing Covid shot does not currently face.