An independent panel of advisers to the Food and Drug Administration will meet on Tuesday to consider options for updating the coronavirus vaccines for a booster campaign aimed at warding off fall or winter spikes.
The experts will vote at the end of the day’s meeting on whether to reformulate the vaccines to target Omicron or one of its sub-variants, and if so, which ones. You can watch the meeting live on YouTube here, scheduled for 8:30 a.m. Eastern.
Discussion questions circulated by the FDA show that the advisory group will also be asked whether vaccines that combine the original formulation with one targeting Omicron would be preferable to vaccines targeting Omicron alone. Data supporting the option combining the so-called “prototype” or existing vaccines with Omicron has so far received mixed reviews, with regulators suggesting in briefing materials for Tuesday’s meeting that such a design is “already somewhat outdated.”
Regulators also plan to ask the advisors whether healthcare providers should continue to use the original vaccine formulation for people who have not yet been fully vaccinated this fall if the booster injection formulation changes.
Omicron subvariants, known as BA.4 and BA.5, now make up more than a third of cases in the country, a possible hint of what could be circulating later this year. A vaccine that protects against those versions of the virus may be of most interest to the FDA panel and federal scientists who will determine where to focus.
Members of the FDA committee may be divided on who should get new vaccines. Some might say a fall booster will be broadly necessary, while others might argue that because current vaccines against severe Covid-19 have held up, the next round of injections should be limited to high-risk individuals. , at least until the start. dr. Paul Offit, a vaccine expert at Children’s Hospital in Philadelphia and a member of the committee, has said only people over 70 and over 50 with serious underlying conditions are likely to need a booster shot.
The possibility of a more advanced vaccine has been teased for months by federal health officials, who have warned that as the virus advances rapidly, vaccine-induced protection against infection has faded, potentially even reinfecting some Americans within the span of several months.
In briefing materials published ahead of Tuesday’s meeting, FDA officials said the risk of another major Covid outbreak will increase later this year “because of the combination of declining immunity, further evolution of variants and increased indoor activity.”
The World Health Organization said this month that updated versions of the vaccines should be studied because their protection against symptomatic diseases has deteriorated so rapidly.
Moderna and Pfizer, the makers of the two most widely used vaccines in the United States, have both studied Omicron-specific vaccines, expecting them to be seriously considered the fall booster option. But the research is complicated by the sub-variants, for which neither company has developed shots yet.
If the government decides it wants a booster shot targeting BA.4 and BA.5, the vaccine manufacturers will have to race to produce the doses by the fall. Pfizer may be able to meet an October deadline, according to people familiar with the company’s operations, while Moderna has said it probably won’t have the option ready until late this year or early next year.
Tuesday’s discussion is likely to serve as a referendum of sorts about the future of the pandemic in the United States and whether the rapidly evolving virus could lead to a significant spike in hospitalizations later this year. Justin T. Lessler, an epidemiologist at the University of North Carolina, Chapel Hill, will model the committee on the trajectory of the virus.
The death toll has stayed below 400 a day in recent weeks, even as Omicron cases rose this spring, with people dying from Covid at a rate close to the pandemic’s lowest. Infectious disease experts have attributed the trend to the protection Americans have received through vaccination and infection, as well as new treatments, such as the oral antiviral pill Paxlovid.
