WASHINGTON (AP) — The U.S. on Wednesday approved its first update on COVID-19 vaccines, booster doses targeting the most common microbe strain today. Shooting could begin within days.
The Food and Drug Administration’s move alters the recipe for shots made by Pfizer and rival Moderna that have already saved millions of lives. The hope is that modified amps will dampen another winter surge.
“You’re going to see me on the front lines,” FDA vaccine chief Dr. Peter Marks, just before his agency cleared the new installments.
Until now, vaccines for COVID-19 have targeted the original strain of the coronavirus, even as vastly different mutants emerged. The new US boosters are combination or “bivalent” shots. They contain half of this original vaccine recipe and half of the protection against the newer versions of omicron, called BA.4 and BA.5, which are considered the most contagious yet.
The combination aims to increase cross-protection against multiple variants.
“It really provides the broadest opportunity for protection,” Pfizer vaccine chief Annaliesa Anderson told the AP.
Updated boosters are only intended for people who have already had the original vaccinations, using the original vaccines. The doses made by Pfizer and its partner BioNTech are for anyone 12 years and older, while Moderna’s updated shots are for adults — if it’s been at least two months since their last primary vaccination or their last booster. They should not be used for primary vaccinations.
There’s one more step before a fall booster campaign begins: The Centers for Disease Control and Prevention must recommend who should get the extra shot. An influential CDC advisory panel will discuss the evidence Thursday — including whether people at high risk of COVID-19 should go first.
“As we head into fall and begin spending more time indoors, we strongly encourage anyone who qualifies to consider getting a booster dose with a bivalent COVID-19 vaccine to provide better protection than current variants,” the FDA Commissioner Dr. Robert Califf said in a statement.
The US has purchased more than 170 million doses from the two companies. Pfizer said it could ship up to 15 million of those doses by the end of next week.
The big question is whether people tired of vaccinations will roll up their sleeves again. Just half of vaccinated Americans received the first recommended booster dose, and only a third of those 50 and older who were told to receive a second booster did so.
It’s time for U.S. authorities to better explain that the public should expect an updated COVID-19 vaccination every now and then, like the fall flu shot or a tetanus booster after biting a rusty fingernail, said immunologist E. John Wherry from the University of Pennsylvania.
“We need to rebrand it in a socially normal way,” rather than a panicked response to new mutants, Wherry said. “Give a clear, long-term set of expectations.”
Here’s the rub: The original vaccines still offer strong protection against serious illness and death from COVID-19 for most generally healthy people, especially if they received that important first booster dose. It’s unclear how much more benefit an updated booster would bring — beyond a temporary jump in antibodies capable of warding off a microbe infection.
One reason: The FDA cleared the modifications before human studies, a step toward eventually treating the COVID-19 vaccine updates more like annual flu shots.
First, the FDA reviewed human studies of previous attempts by Pfizer and Moderna to update their vaccines — shots that matched the micron strain that hit last winter. This recipe change was safe and substantially boosted antibodies targeting the earlier variant—better than another dose of the original vaccine—while adding some protection against today’s genetically distinct BA.4 and BA.5 omicron versions.
But the FDA has ordered the companies to make even more updated doses targeting these newer microbe mutants, sparking a race to roll them out in less than three months. Instead of waiting a few more months for additional human studies on this prescription tweak, Marks said animal tests showed the latest update promotes “a very good immune response.”
The hope, he said, is that a vaccine that matches the current variants that are spreading could do a better job of fighting infection, not just severe disease, at least for a while.
What’s next? Even when modified plans are released, Moderna and Pfizer conduct human studies to help assess their value, including how they hold up if a new mutant emerges.
And for children, Pfizer plans to ask the FDA to allow updated boosters for children ages 5 to 11 in early October.
It’s the first U.S. update to the COVID-19 vaccine prescription, an important but expected next step — much like how flu vaccines are updated each year.
And the US is not alone. Britain has recently decided to offer adults over 50 a different booster option from Moderna, a composite download that targets this initial strain BA.1 omicron. European regulators are considering whether to approve one or both of the updated formulas.
AP Health writer Matthew Perrone contributed to this report.
The Associated Press Health and Science Section is supported by the Howard Hughes Medical Institute Science Education Division. AP is solely responsible for all content.