IIn two votes, each 13 to 1, the U.S. Centers for Disease Control and Prevention (CDC) immunization committee recommended that Americans receive an Omicron-specific booster dose of the COVID-19 vaccine. After a day-long discussion of the data available Sept. 1, the panel recommended recalls from two manufacturers — Pfizer-BioNTech and Moderna, both of which make mRNA-based vaccines; the new booster made by Pfizer-BioNTech is for people 12 and older, and the Moderna vaccine is for adults 18 and older. The group also advised people to wait at least two months after their previous dose before receiving one of the two new boosters. Hours after the vote, CDC Director Dr. Rochelle Walensky accepted the committee’s advice to recommend the new booster.
Omicron boosters can “help restore protection that has declined since previous vaccination and have been designed to provide broader protection against newer variants,” she said in a statement announcing her decision. “This recommendation follows a full scientific assessment and extensive scientific discussion. If you’re eligible, there’s no bad time to get your COVID-19 reminder and I strongly encourage you to get it.
The CDC guidance comes a day after the U.S. Food and Drug Administration (FDA) cleared Omicron-specific injections by the two companies.
The booster is the first to target a variant of the SARS-CoV-2 virus. All vaccines that have been approved by the FDA and recommended by the CDC so far, as well as booster doses authorized by the agencies, have targeted the original virus that emerged in 2019. The latest Omicron booster targets BA.4 and BA. 5 subvariants of the virus, which now account for almost all new COVID-19 infections in the United States
The Omicron BA.4/5 recall represents a step change in how health officials hope to protect the public. Rather than recommending booster doses every few months, as they have advised since vaccines became available in late 2020, they now hope to switch to a vaccination schedule that mimics that of the flu, with an annual injection. The newly authorized Omicron booster will replace existing boosters of the original COVID-19 vaccine. Everyone aged 12 or over will be eligible to get one, regardless of how many previous booster doses they have received so far.
In recommending the booster, the CDC’s panel of independent vaccine experts acknowledged that while they have authorized boosters before, this one is different in several ways. Not only is it the first to target a variant of the virus, it is also the first to contain genetic material against two versions of the virus – the original or ancestral strain, and Omicron BA.4 and BA.5, in one so- called bivalent vaccine. In the case of the Pfizer-BioNTech and Moderna booster, the dose is the same as the previous boosters that were authorized, but split between the original strains and Omicron BA.4/5.
Perhaps of most concern to committee members, the two companies’ boosters have yet to be tested on people, meaning there’s no direct evidence that the injections will actually stop people from falling. seriously ill with COVID-19. Pfizer-BioNTech and Moderna developed Omicron boosters after an FDA expert panel met in June and asked vaccine makers to target the BA.4 and BA.5 subvariants. The companies had developed a booster that combined the original strain and an earlier version of Omicron, BA.1, and was shown to help boost anti-virus antibody levels against Omicron. But since BA.4 and BA.5 quickly overtook BA.1 in causing infections, the FDA requested a bivalent vaccine including BA.4 and BA.5. Both companies submitted data to the FDA in August from animal studies showing that their boosters raised antibody levels in mice.
The FDA and CDC scientists point out that the animal data is sufficient to recommend the newest booster, given the totality of evidence supporting the safety and effectiveness of previous versions of the vaccines so far. They point to real-world data involving millions of people who have been vaccinated and boosted up to two times with the original vaccine, as well as data on the bivalent BA.1 booster that was never marketed. Dr. Doran Fink, Deputy Clinical Director of the Division of Vaccines and Related Products Applications at the FDA, opened the discussion by telling members that “the FDA, in its authorization, considered the totality of the evidence, which consisted mainly of an extrapolation approach based on data from clinical trials with similar bivalent vaccine formulations consisting of the original component and the Omicron BA.1 subline, as well as extensive experience in the use of the original monovalent vaccine both as a primary series and as a booster. Additionally, the FDA considered supporting data from certain animal studies that provided additional assurance on our extrapolation approach.
This is a different approach to that taken by UK and Canadian health authorities, who decided to allow the bivalent booster manufactured by Moderna against the BA.1 sub-variant.
This leaves some public health experts in the United States concerned about the Omicron BA.4/BA.5 recall recommendation. Dr. Pablo Sanchez, professor of pediatrics at Ohio State University and the only dissenter to vote against the recommendation for the new Omicron booster, said, “I think we really need human data. It’s a new vaccine, a new platform, and there’s a lot of vaccine hesitancy already, so we need human data. I really think it’s premature and I wish we had seen that human data.
Sanchez, however, acknowledged that he would still likely get the recall because he was persuaded by the FDA’s argument that the available evidence, even if indirect, suggests the new vaccine is both safe and potentially efficient. There’s also the fact that each year the annual flu vaccine is approved without data demonstrating its effectiveness against the latest circulating flu strains, which makes vaccination a bit risky, albeit calculated. “I remind the committee that every year we recommend influenza vaccines based on new strains without clinical studies being done,” said Dr. Melinda Wharton, of the CDC’s National Center for Immunization and Respiratory Diseases and executive secretary of the CDC committee. “In many ways, it’s analogous to that.”
In favor of recommending a booster switch, CDC researchers have documented that people immunized with the original vaccine and boosters have decreasing, and in some cases very weak, protection against infection with the sub -variant Omicron BA./BA.5. While the original vaccines and boosters prevent people from getting sick enough to require hospitalization, even that protection appears to be waning as more fully immunized people become moderately ill after being infected with BA.4/BA.5. Modeling presented by CDC scientists also showed that if health authorities were to wait a few more months, until November, for human studies to be completed on the BA.4/5 booster, an estimated 137,000 more people would be hospitalized. and nearly 10,000 people would die of COVID-19[FEMININE[FEMININE
That’s why the government is pushing to allow the new booster, but it’s unclear whether the public will take the advice of health officials and rush to get boosted, especially in an environment where people are tired of repeated reminders and increasingly skeptical of their effectiveness. . As more and more people become infected with the highly transmissible variant of Omicron BA.4/5, they feel that their immunity from having been sick outweighs the need to be boosted. And some health officials aren’t convinced that the BA.4/5 booster provides any additional protection against disease over the original vaccine, which becomes even more questionable when it comes to people who have been immunized and strengthened, and who have recently been vaccinated. infected with Omicron BA.4/5, as many Americans have been recently. Dr. Paul Offit, a professor at Children’s Hospital of Philadelphia and a member of the FDA’s Vaccine Expert Panel, says there isn’t enough data to recommend the new booster and won’t agree. probably not for this vaccine. “The CDC’s clearance and recommendation doesn’t change the data, which is uncomfortably sparse,” he told TIME. “We still don’t have human data on this vaccine. I don’t plan on getting this vaccine, mainly because I don’t think I need it. I had three previous doses and a mild natural infection.
Some of the data presented to CDC committee members addressed this question of what additional benefit most people, who are vaccinated and boosted, will get from the Omicron-specific booster. Although it makes biological sense to match the booster to the circulating virus, which is currently the Omicron BA.4/5 subvariant, the studies are not yet complete. “t replace human trials.
Both companies are conducting human studies and expect to have that information in a few months, but in the meantime people will have to make their own decisions about how comfortable they are with getting the new booster dose. . “I think it’s a big step towards simplification,” Wharton told the committee. “Hopefully we’re moving towards something that’s simpler and doesn’t require such frequent changes in the future. Clearly we’re not there yet, but I think it’s a big step forward.
The US government has already purchased 170 million doses of the Omicron BA.4/5 booster from the two manufacturers, and Pfizer-BioNTech has already shipped 100,000 doses to 62 sites that arrived on September 1. After Labor Day weekend, the company plans to deliver 3 million doses to more than 3,000 sites. Moderna is manufacturing 66 million doses to meet the government’s order, but did not say how many have been shipped so far.
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