The White House still expects the new COVID boosters to offer better protection, but two new studies cast doubt

The White House’s top COVID-19 official says he’s still awaiting protection against the Omicron BA.5 variant offered by new COVID vaccine boosters will be better than their predecessors, despite two studies that seem to question that assumption. In an interview with CBS News, Dr. Ashish Jha also said he doesn’t think another immediate change to the COVID boosters will be needed.

Jha’s comments come after researchers found data in two smaller groups of volunteers suggesting that the updated boosters provided only similar, but not better, boosts of antibodies to BA.5 compared to the original vaccine formulation.

“I really think the protection against infection is going to be better than if you were getting the original prototype booster,” Jha told CBS News.

Jha said he was not surprised by the new study results and praised the two scientists — Dan Baruch of Harvard Medical School and David Ho of Columbia University — who led each of the research teams behind the preliminary findings.

However, he predicted that “well-controlled trials” with “larger samples” currently being conducted by vaccine manufacturers may yield more favorable results about the effectiveness of boosters.

The studies showed higher antibody responses after the updated booster, Jha said, even if they were too small to be statistically significant.

“I expect we’ll see at least this benefit, possibly greater, in the Pfizer and Moderna studies,” Jha said.

Dr. Ashish Jha
White House COVID-19 Response Coordinator Dr. Ashish Jha speaks at the daily press briefing at the White House on June 2, 2022.

Kevin Deitch/Getty Images

Jha’s comments are in line with expectations previously expressed by federal health officials throughout the Biden administration, who have argued for months that the updated boosters released this fall would outperform the original formulations.

In a statement, the FDA said data “from larger, well-controlled studies that are not subject to the same limitation as these smaller studies are expected to be available in the near future” and urged Americans to seek an updated booster.

“Furthermore, even modest improvements in vaccine response to bivalent boosters can have important positive public health implications,” FDA spokeswoman Abby Capobianco said.

The new boosters are known as “bivalent” because they include both a component targeting the original “prototype” strain and another targeting the BA.4 and BA.5 variants.

Early data from animals tested with the new photos was promising. Previous versions targeting other strains tested on humans also suggested that a bivalent formula would also offer at least a “gradual” improvement, health officials concluded.

And with new strains on the rise in the US and around the world, officials hoped the new vaccines would do better at fending off a dreaded winter tide from the virus.

“The one I pay most attention to in the United States is BQ.1.1which is a BA.5 derivative and based on everything we understand about immunology, your protection against BQ.1.1 will be significantly better after bivalent BA.5 [booster]Jah said.

“Humble and insignificant”

But this week, two studies appeared to upend those expectations.

“There was no significant difference in the neutralization of any SARS-CoV-2 variant tested between individuals who received a fourth monovalent vaccine and those who received a fourth dose of bivalent vaccine,” concluded one study, which has not yet peer-reviewed, published by the team led by Ho.

The scientists took blood from people roughly a month after they received the new injection and tested their antibody responses against
“pseudoviruses” — essentially mock-ups of various variants, including BA.5.

Barouch’s team performed a similar experiment against BA.5. They found only a “modest and insignificant” improvement from the updated boosters in their study, which is also not yet peer-reviewed.

“If this very small difference holds up in a much larger study, then a much larger study might actually say it’s a statistically significant difference.” The question is is it clinically relevant? And I don’t believe that level of difference is clinically significant,” Baruch said in an interview.

Barush said a phenomenon called immune imprinting may be to blame for the disappointing immune response to the updated booster.

Immune imprinting, also known as “original antigenic sin,” refers to the theory that people’s initial exposure to an earlier strain of the virus—either from infection or vaccination—can interfere with the body’s ability to produce antibodies against new ones. strains.

Both vaccines companies and health officials have previously downplayed the obstacle the phenomenon could pose to the new shots.

Barush acknowledged that there is a possibility that responses against BA.5 may improve after more weeks after the updated booster, but cautioned that we have seen antibodies decline in the months after previous mRNA COVID shots.

His team also measured another part of the immune response from T cells. They were not “substantially” enhanced by additional injections of the bivalent or original formulations.

“We all talk about antibodies, the focus has been on antibodies, but there are two sides to the immune system: antibodies and T cells. And we believe both are important in protecting against severe disease,” Baruch said.

Update on vaccines

The new studies come as the Biden administration prepares for key decisions about the nation’s supply of a COVID-19 vaccine.

Millions of doses of the original monovalent vaccine, which is still used for primary vaccine series, are due to expire in the coming months. Boosters have yet to be approved for the youngest age group: children up to 6 months of age.

The federal government’s supply of updated boosters is about to run out next year as a result of a stalled request for COVID funding on Capitol Hill that will prompt a shift to the private market.

FDA and CDC officials said they expect to decide in the winter whether and how to update the vaccine regimen going forward.

Capobianco confirmed that the FDA still plans to convene a meeting this winter of its outside advisers, the Advisory Committee on Vaccines and Related Biologics, to discuss the composition of the primary series.

These decisions will depend in part on how the updated photos are presented.

“We will have our BA.4/5 data by the end of the year and ours will be statistically powered,” Moderna spokesman Chris Ridley said in an email.

Ridley also pointed to the results of a previous Moderna bivalent formulation targeting the BA.1 variant, which was published in The New England Journal of Medicine a few weeks ago.

Pfizer and their German partner BioNTech announced they found “positive early data” from their updated photos earlier this month. Pfizer spokesman Steve Dannehy said they expect to “have additional data in the coming weeks” about the shots.

“We will want to make policy decisions based on more definitive, larger studies that are coming soon,” Jha said.

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