FDA scientists endorse Moderna Covid-19 vaccine, as documents provide new hints on efficacy

Scientists at the Food and Drug Administration endorsed the Covid-19 vaccine developed by Moderna as safe and efficacious on Tuesday, one day after the first doses of a competing vaccine from Pfizer and BioNTech were delivered across the United States.

The FDA reviewers said that the two-dose vaccine “was highly effective” in preventing symptomatic Covid-19 from occurring “at least 14 days after the receipt of the second dose.”