FDA proposes moving to annual coronavirus vaccine, mimicking flu model

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The Food and Drug Administration is proposing a significant change in how the coronavirus the vaccine is manipulated: switching to an annual injection that targets the strain that is expected to pose the greatest threat during the following winter – a system similar to that used for the flu vaccine.

The agency, in background papers released on Monday for a meeting this week with its vaccine advisers, said evidence suggests that “in the future, most individuals may only need to receive one dose” of a vaccine against coronavirus “to restore protective immunity for a period of time”. The change in strategy will be one of the topics discussed at the meeting, scheduled for Thursday.

The proposed change aims to reduce the complexity of the vaccine schedule for the public, physicians and manufacturers. It also reflects the view that ‘chasing variants’ with ever-changing reminder wordings is ultimately futile, in part because the public has little interest in receiving repeated injections, according to a person familiar with the situation. who spoke of the condition of anonymity because they weren’t allowed to talk about it publicly.

The FDA would choose the annual strain for injections each June, in time for updated injections to be manufactured and then administered in September, as part of an annual inoculation campaign. The goal would be to select the strain most likely to be dominant in the winter, when people are indoors and covid cases typically spike.

If there was an emergency — such as the emergence of a more dangerous variant that was also able to evade immunity — the FDA would call an impromptu meeting of vaccine advisers and select a new strain to counter the threat, a said the agency.

While most people would receive an annual injection, under the new plan, people who are elderly or very young, immunocompromised or have serious health conditions may need two doses, according to the FDA briefing document.

Last fall, the agency licensed an updated bivalent vaccine that targeted the original strain of the virus and the omicron BA.4 and BA.5 subvariants. But by the time the booster was launched, another variant was rapidly rising. In addition, the uptake of the vaccine has been low even among the most vulnerable older people. Fewer than 40% of people 65 and older have received the updated vaccine, according to the Centers for Disease Control and Prevention.

The FDA, according to the document, is also seeking to withdraw the original vaccine formula that entered the market in late 2020 — the monovalent that focuses on the original virus. This means that the updated bivalent booster would be used for both the original two-shot series of the vaccine and for the booster – until a new strain is chosen.

“This simplification of vaccine composition should reduce complexity, decrease vaccine administration errors due to the complexity of the number of different vial presentations, and potentially increase vaccine compliance by allowing for clearer communication,” said the FDA.

The FDA’s change in strategy was first reported by NPR.

Scientists say they have learned that a vaccine offers the best protection against the virus for the first three or four months after injection. For a few months after that, the injections remain protective against serious illnesses, but then the protection wanes. The hope is that the lowest level of protection will occur during the summer, when covid-19 outbreaks tend to be less severe.

The fact that many Americans have been infected with the virus should provide additional protection, scientists say.

The FDA has been criticized by some, including members of its vaccine advisory committee, for pushing for the broad use of variant-specific boosters to ward off covid. Paul A. Offit, panel member and vaccine expert at Children’s Hospital of Philadelphia, wrote in the New England Journal of Medicine recently that it is futile to try to “prevent all symptomatic infections in healthy young people by doping them with vaccines containing mRNA from strains that could disappear a few months later”.

Offit said such boosters should be reserved for the elderly, or those who are immunocompromised or have multiple medical conditions.

But Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, expressed concern, saying he’s not sure an annual flu pattern will work for covid, in part because mRNA vaccines don’t last a whole year. and because it is necessary to know more about the variants.

“There may be too many unknowns,” he said.

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