by Lauren Niergaard and Matthew Perrone
At least some US adults may get updated COVID-19 shots this fall, as government advisers voted on Tuesday that it’s time to tweak the booster dose to better match the most recent virus variants. Is.
Food and Drug Administration advisors now wrestle with how to modify dosages when there’s no way to know how the rapidly mutating virus will evolve by the fall — especially since people receiving today’s recommended boosters for COVID-19. Strongly protect against the worst consequences of -19.
Ultimately, the FDA panel voted 19-2 that the COVID-19 booster should contain some version of the super-infectious Omron version, to be ready for an anticipated fall booster campaign.
“If we wait any longer, we will be eight balls behind,” said Dr. Mark Sawyer, a consultant at the University of California, San Diego.
The FDA will have to decide the exact prescription, but hopes for a combination shot that adds protection to the original vaccine against Omicron or some of its newer relatives.
FDA vaccine chief Dr. Peter Marks said, “None of us have the crystal ball” to know the next dangerous version. But “we can at least get the immune system closer to being able to respond to what’s going on” rather than the older virus strains now.
It is unclear who will be offered the tweaked boosters – they may only be solicited for older adults or those at high risk from the virus. But the FDA is expected to make a decision on prescription changes within days and then Pfizer and Moderna seek authorization for appropriately updated dosages, time for health officials to settle on a decline strategy. .
Current COVID-19 vaccines have saved millions of lives globally. With a booster dose, those used in the US maintain strong protection against hospitalization and death, but their ability to prevent infection has declined significantly when Omicron appeared. And the Omicron mutant that caused winter growth has been replaced by its genetically distinct relatives. According to the Centers for Disease Control and Prevention, the two newer Omicron cousins, called BA.4 and BA.5, now account for half of US cases.
Pfizer and Moderna were already making boosters that previously provided protection to Omicron mutants. Their combination shots, which scientists call “bivalent” vaccines, significantly increased the level of antibodies capable of fighting that type, far more than giving another dose of today’s vaccine.
Both companies found that the tweaked shots offered some cross-protection even against those worrying BA.4 and BA.5 mutants, but not nearly as much.
Many scientists support the combination approach because it preserves the proven benefits of the original vaccines, including some cross-protection against other mutants that have arisen during pandemics.
The question facing the FDA is the correct prescription change. Both companies said they’ll have plenty of Omicron-targeted combo shots by October, but Moderna said that switching to targeting Omicron’s newest relatives could delay its version by another month.
Further complicating the decision is that only half of vaccinated Americans have received that all-important first booster. And while the CDC says the protection from hospitalization for older adults is somewhat reduced, a second booster that is recommended for people 50 and older seems to restore it. But only a quarter of those eligible for the additional booster got one.
Marks said that by tweaking the shots, “we’re hoping we can convince people to take that booster to bolster their immune response and help prevent another wave.”
Logistics will be challenging. Many Americans haven’t gotten their first vaccinations yet, including young children who have just become eligible — and it’s unclear whether the tweaked booster could eventually replace the primary vaccine. But FDA advisors said it’s important to go ahead and study updated vaccine recipes in children as well.
And another complication: A third company, Novavax, is awaiting FDA authorization of a more traditional type of COVID-19 vaccine, protein-based shots. Novavax argued Tuesday that a booster of its routine vaccine promises a good immune response against the new Omicron mutants without a prescription change.
World Health Organization advisers recently stated that omicron-tweaked shots would be most beneficial only as boosters, as they should broaden people’s cross-protection against multiple types.
“We don’t want the world to lose faith in the vaccines currently available,” said Dr. Kanta Subbarao, a virologist who chairs the WHO committee.
The Associated Press Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. Associated Press is solely responsible for all content.