FDA OKs Novavax COVID-19 booster dose

WASHINGTON - U.S. regulators on Wednesday authorized a booster dose of the COVID-19 vaccine made by Novavax.

The Food and Drug Administration said the new booster option is for people 18 and older who can’t get the updated omicron-targeting Pfizer or Moderna boosters for medical or accessibility reasons -- or who otherwise would not receive a COVID-19 booster shot at all.

The FDA specified the additional Novavax shot was to be used as a first booster -- not for people who've already had one or more booster doses already — at least six months after completing their primary shots.

FILE - In this photo illustration a COVID-19 vaccine is seen with the Novavax logo in the background. (Nikos Pekiaridis/NurPhoto via Getty Images)

Novavax's initial two-dose shots have been available since the summer. Novavax is a protein-based vaccine unlike the other COVID-19 vaccines available in the U.S. including Pfizer, Moderna or Johnson & Johnson.

About 48 percent of Americans who received their primary vaccinations have never received that all-important first booster.

"Offering another vaccine choice may help increase COVID-19 booster vaccination rates for these adults," said Novavax CEO Stanley Erck in a statement.

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The Centers for Disease Control and Prevention also signed off on the decision after the FDA.

U.S. health officials have been encouraging Americans to get those updated Pfizer and Moderna boosters to bolster protection against the most common omicron strains ahead of an expected winter surge.

The new Novavax booster is made with that company's original formula; it still is testing an omicron-targeted recipe.