Why Omicron Boosters Aren’t Tested In Humans
Wmeaning that nearly all new COVID-19 infections in the United States come from the Omicron BA.4 and BA.5 subvariables, health officials are considering switching to a different vaccine to protect public protection.
White House COVID-19 Response Coordinator, Dr. Ashish Jha expectations The first Omicron-specific boosters will be available mid-September at the earliest, if the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) allow and recommend injection. At the end of August, both Pfizer-BioNTech and Moderna submitted a request to the FDA for authorization for their specific Omicron booster.
But with fall and winter fast approaching — seasons when respiratory viruses like SARS-CoV-2 spread more efficiently, when students return to school and people gather indoors — getting ready Enhanced medication requires a more effective review and management process. And that includes looking at safety and efficacy data from animals, not people.
Back in June, FDA’s Independent Panel of Vaccine Experts Meets to consider switching the country to a new booster that targets Omicron, given how quickly that variant is dominating for new infections. At the time, the two largest COVID-19 vaccine manufacturers, Pfizer-BioNTech and Moderna – both of which make mRNA-based vaccines – were already developing shots against an earlier variant of Omicron, BA. .first. The panel decided that if health authorities were to change the booster shot to target Omicron, the subsequent shot that would have to protect against the subvariables BA.4 and BA.5, would continue to occupy most cases in winter.
They asked vaccine manufacturers to develop a new vaccine, an original vaccine combination that also targets Omicron BA.4 and BA.5. In late August, both companies submitted their new dual-value vaccine data to the FDA for emergency use authorization.
However, given the short time they had to develop the injectable, the data included only information on the safety and effectiveness of the booster in animals. Human studies are planned and will continue even if the FDA and CDC decide to allow the shots and the government begins distributing them. The FDA also decided to review the animal study data without consulting its advisory committee again.
That has been divided by vaccine experts. Dr Paul Offit, a member of the advisory committee, said the strategy made him “uncomfortable” for a number of reasons. He noted that the data presented from Pfizer-BioNTech and Moderna in June regarding their BA.1 booster shot, focused on the levels of antibodies against the virus the vaccine produced, was amazing. “They have shown that the neutralizing antibody titer against Omicron is 1.5 to two times higher than that produced by a single dose of ancestral vaccine,” he said. “I would like to see clear evidence of a significant increase in neutralizing antibodies, more potent than we have seen for BA.1, before launching a new product. At least we owe it to that. “
Although it takes longer to conduct human studies, Offit said even a small trial of about 100 people to measure their antibody levels after being injected with the BA.4/5 booster would also help. will be useful. “You can push people up and measure their neutralizing antibodies two weeks later,” he said. Such information can also be important in setting realistic expectations for an Omicron intensifier. The public may feel it’s a panacea that heralds the end of the pandemic, but there isn’t any data to suggest that the booster will protect people not only from getting sick, there can be unrealistic expectations of what enhancers can do. “Honestly, I was a bit nervous when I heard this [booster] would be a miracle,” said Offit.
Other experts see it a little differently. Based on the fact that mRNA vaccines have been administered to millions of people to date, with relatively few safety concerns, and given that the vaccine has been effective in protecting people from hospitalization or die from COVID-19, even in the latest wave of Omicron they argue that changing the virus strain in the vaccine does not require extensive testing like the original injection. “The whole evidence is relevant here,” said Dr Ofer Levy, director of the precision vaccine program at Boston Children’s Hospital and a member of the FDA’s vaccine advisory committee. “We are in a situation where we need to turn around when variations appear and if we try to be too rigid in our approach we will always fall behind and not give the population the ultimate protection.” superior.”
Levy says that the latest Omicron-specific booster that the FDA is reviewing contains a combination of mRNA targets against both the original virus and Omicron BA.4/BA.5, so the data is on safety. and the effectiveness of the parent vaccine in protecting against hospitalizations and related deaths. Although the data on this vaccine comes from animals, using that data to decide whether to allow booster injections is a matter of “hedging bets”. There is data to show that even vaccinated and vaccinated people can get mild to moderate COVID-19 disease, because their vaccine protection is waning, thus enhancing with an injection more consistent with the currently circulating Omicron vaccine is a reasonable bet, even. if the data on its effectiveness comes from animals rather than humans. “I think it was the right decision,” Levy said.
There is no guarantee that the FDA will authorize a new dual-value vaccine, although all indications are that authorization could come in a week or so. If the shots are released and people are boosted, health officials will carefully monitor the data from those vaccines to make sure that the assumptions they make about safety and effectiveness. of the booster injection is preserved. And the upcoming winter hospitalization rates will reveal whether betting on the new Omicron booster is the right decision.
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