WASHINGTON — As expected, the FDA issued an emergency use authorization (EUA) for Moderna’s mRNA vaccine against COVID-19 late Friday, following the pattern laid down last week for Pfizer and BioNTech’s similar product.
On Thursday, an FDA advisory committee overwhelmingly backed the vaccine’s availability in a 20-0 vote, with one abstention, for adults 18 and older under an EUA. The Moderna vaccine is administered in two doses given 28 days apart.
FDA commissioner Stephen Hahn, MD, noted in a statement that these standards and the review process was the same used in reviewing the first vaccine, and included “input from independent scientific and public health experts as well as a thorough analysis of the data by the agency’s career staff.”
Results from the vaccine’s pivotal trial of more than 30,000 participants, indicated an overall efficacy of 94.1% (95% CI 89.3%-96.8%) for preventing clinical illness with confirmed infection. It was somewhat less effective in participants 65 and older, at 86.4% (95% CI 61.4%-95.5%).
Notably, though, efficacy against preventing asymptomatic infection was not addressed in the study.
As with the Pfizer/BioNTech vaccine, flu-like systemic symptoms and injection-site pain were the most common adverse effects. Deaths were no more common in the vaccine arm than in those receiving placebo. Three cases of Bell’s palsy were noted in vaccine recipients versus one in the placebo group, too few to determine whether the risk was genuinely increased. No anaphylactic reactions were seen “with close temporal relation to the vaccine,” FDA staff said in summarizing the trial results.
However, in the advisory committee meeting, both FDA staff and Moderna said they are keeping closer tabs on severe allergic reactions. FDA staff said they are coordinating with Pfizer to revise fact sheets to warn about risk of severe allergic reactions for the vaccine and will do the same for Moderna.
Unlike the rival product, though, Moderna’s vaccine is not yet authorized for people younger than 18. The company began dosing adolescents earlier this month in a new trial with participants as young as 12.
The CDC’s Advisory Committee on Immunization Practices is expected to meet Saturday to discuss the vaccine and vote on whether or not to recommend it for use in adults.
Moderna said Dec. 11 that it planned to deliver 20 million doses to the U.S. government by the end of December, under its contract with Operation Warp Speed (OWS), the federal program on COVID vaccines and therapeutics. OWS officials said on Thursday that 5.9 million doses would be available this coming week following an EUA. Moderna is committed to ship a total of 200 million doses to the U.S. through June 2021.