White House still hopes new COVID boosters will provide better protection, but two new studies cast doubts

Top White House COVID-19 official says he still expects protection against Omicron BA.5 version New COVID Vaccine Booster would be better than its predecessors, despite two studies that question that assumption. In an interview with CBS News, Dr Ashish Jha also said that he doesn’t think there will be a need for another imminent change in the COVID booster.

Jha’s comments come after researchers found, in two small groups of volunteers, data suggesting that the updated boosters only provide similar, but not better, antibodies against BA.5 than the original vaccine formula. Huh.

“I think the protection against infection would be better if you got the original prototype booster,” Jha told CBS News.

Jha said he was not surprised by the results of the new study and praised the two scientists – Dan Baroche of Harvard Medical School and David Ho of Columbia University – who each led the research team behind the initial findings.

However, he predicted that “well-controlled trials” with “larger samples” that are now underway from vaccine manufacturers could yield more favorable results regarding the booster’s performance.

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

“I expect we’re going to see a benefit of at least that size, probably bigger, 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 Dietch/Getty Images

Jha’s comments are in line with expectations previously voiced by federal health officials in the Biden administration, who have argued for months that the boosters updated this fall will outperform the original formulation.

The new boosters are known as “bicomponents” because they include one component targeting the original “prototype” strain and another aimed at the BA.4 and BA.5 variants.

Initial data from animals tested with the new shots were promising. Previous versions targeting other strains tested on humans also suggested that a divalent formulation would also offer at least an “incremental” improvement, health officials concluded.

with and New strains are on the rise In the US and around the world, officials were hopeful the new vaccine would outperform Stopping an Apprehended Winter Boom Why virus?

“The one I’m paying the most attention to in the United States is BQ.1.1which is BA.5 Derivative, and based on everything we understand about immunology, your protection against BQ.1.1 is going to be a lot better then BA.5 divalent. [booster]Jha said.

“minor and insignificant”

But this week, two studies lived up to those expectations.

One study concluded, “There was no significant difference in neutralizing any SARS-CoV-2 variant tested between individuals receiving a fourth monovalent vaccine and individuals receiving a fourth dose of a bivalent vaccine.” Posted by team led by Ho.

Scientists took blood from people about a month after getting the new shot and tested their antibody responses against them
“Pseudovirus” – Essentially a variety of mock-ups, including BA.5.

Barouch’s team did a similar experiment against BA.5. They found only “slight and nonsensical” improvements in their study from the updated booster, which has yet to be peer-reviewed.

“If that very small difference happens in a very large study, then a very large study can actually say it is a statistically significant difference. The question is, is it clinically relevant? And I don’t believe it. That level of difference is clinically relevant,” Barouch said in an interview.

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

The immune imprint, also known as “original antigenic sin”, refers to the theory that the initial exposure people had to an earlier strain of the virus – either by infection or vaccination – produced antibodies to the new strains. may hinder the body’s ability to

both vaccines companies And health officials had previously underestimated the odds that the incident could stand up to new shots.

Baruch acknowledged that there is a possibility that the response against BA.5 may improve after more weeks after the updated booster, but cautioned that we saw a decline in antibodies in the months following the last mRNA COVID shots Is.

His team also measured another part of the immune response from T cells. They were “not sufficiently amplified” by bivalents or additional shots from the original formulations.

“All we talk about antibodies has focused on antibodies, but there are two sides to the immune system: antibodies and T cells. And we believe that both are important for protection against serious disease,” Barouch said. Told.

updating vaccines

The new studies come as the Biden administration prepares to make important decisions about the country’s COVID-19 vaccine supply.

Millions of doses of the original monovalent vaccine, which are still being used for the primary series shots, are due to expire in the coming months. The booster still needs to be flagged for the youngest age group: babies under 6 months old.

The federal government’s updated booster supply is on pace to expire next year as a result of a halted COVID funding request on Capitol Hill, which will signal a turnaround in the private market.

FDA and CDC officials have said they expect to decide over the winter whether and how to update the vaccine regimen for the foreseeable future.

Those decisions depend partly on how the updated shots perform.

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

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

Pfizer and their German partner BioNTech earlier this month announced the discovery of “positive preliminary data” from their updated shots. Pfizer spokesman Steve Dennehy said he expects “additional data in the coming weeks” on the shots.

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

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