FDA says fall COVID boosters must target new omicron types : NPR


A nurse fills a syringe with a COVID-19 vaccine in the Staten Island borough of New York on April 8, 2021. The Food and Drug Administration on Thursday recommended that COVID booster shots be changed to better match newer variants of the coronavirus .

Marie Altaffer/AP


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Marie Altaffer/AP


A nurse fills a syringe with a COVID-19 vaccine in the Staten Island borough of New York on April 8, 2021. The Food and Drug Administration on Thursday recommended that COVID booster shots be changed to better match newer variants of the coronavirus .

Marie Altaffer/AP

U.S. regulators told COVID-19 vaccine makers on Thursday that any modified booster shots for the fall will need to add protection against new omicron parents.

The Food and Drug Administration said the original vaccines would be used for anyone still receiving their first round of vaccines. But with waning immunity and the family of super-contagious omicron variants improving to dodge protection, the FDA decided the boosters destined for the fall needed an update.

The recipe: combination shots that add protection against the omicron relatives named BA.4 and BA.5 to the original vaccine. Together, these mutants now account for just over half of new infections in the United States.

It’s still a gamble as there’s no way of knowing if an omicron parent will still be a threat as cold weather approaches or if a new mutant will take their place. And the current Pfizer and Moderna vaccines still offer strong protection against the worst outcomes of COVID-19 as long as people have already received the recommended boosters.

But the combined approach, what scientists call “bivalent” injections, would allow boosters to retain the proven benefits of the original vaccine while adding to its breadth of protection. It’s a common vaccine strategy: flu shots, for example, can protect against four strains of flu and are changed every year depending on what’s circulating.

The FDA’s decision comes after its scientific advisors earlier this week recommended that any booster for a fall campaign should contain a version of omicron – but didn’t decide whether it should be the omicron mutant that caused the surge last winter or genetically distinct parents who replaced it. .

Pfizer and Moderna were already preparing and testing updated boosters against the first omicron mutant in anticipation of an October rollout. They found that adding extra protection was safe – and stimulated the production of more anti-omicron antibodies than just getting another dose of the current vaccine.

Pfizer had started working on another experimental dose to target the new strains which the FDA eventually settled on.

“We continue to collect more data from our BA.4/5 study and will contact you as soon as we are ready to submit it,” Pfizer spokeswoman Jerica Pitts said in a message sent by E-mail.

Moderna told FDA advisers that switching to even newer strains in circulation could delay its recall update by a month. Moderna did not immediately respond to requests for comment on Thursday.

The FDA order does not guarantee that these combination injections would be available in the fall. Manufacturers still have to provide key data before the agency decides whether or not to allow modified boosters — and the Centers for Disease Control and Prevention would then have to decide how they’re used.

For now, a very important first booster of the current vaccine is already requested for all Americans aged 5 and over. People 50 and older are eligible for a second booster. With omicron, authorities say the injections’ protection against COVID-19 hospitalization, while still robust, has slipped somewhat in the elderly and a second booster can help restore it.

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