FDA advisers to consider whether Omicron-specific coronavirus vaccines are needed

“There’s anticipation that we would need a fall booster and what that framework would look like and if a vaccine is needed due to a different variant,” Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials, told CNN.

“This becomes challenging, because is it really a booster if it’s not the same formulation? And should we be talking about it in that way or is it simply a new vaccination?” Freeman added. “We don’t discuss that we have received boosters of flu shots over the years. It’s just part of getting your flu shot every year. So this transition is an important one.”

“By summer, decisions will need to be made for the 2022-2023 season about who should be eligible for vaccination with additional boosters and regarding vaccine composition,” wrote Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research; Principal Deputy Commissioner Dr. Janet Woodcock; and FDA Commissioner Dr. Robert Califf.

“Administering additional COVID-19 vaccine doses to appropriate individuals this fall around the time of the usual influenza vaccine campaign has the potential to protect susceptible individuals against hospitalization and death, and therefore will be a topic for FDA consideration,” they wrote.

‘This is going to be … a transitional year’

The FDA’s vaccine advisers previously met in April to discuss how the composition of Covid-19 vaccines could change to target any new and emerging coronavirus variants. The committee agreed that there needs to be a framework for how and when such changes take place.

FDA’s Marks has called this year a “transitional” one in how we view the evolving Covid-19 vaccine schedule.

“If people who get that boost do well and we seem to have avoided another big wave from October to March-April of next year, we will have gotten people used to that,” he said.

“We have to start thinking about vaccines that we can adjust strains of once a year and make it more of a flu model rather than saying, OK, every five months or four months, you’ll get another booster,” Marks told Bloomberg. “The idea here is that next year we have one campaign, and we don’t have to follow it up with another booster campaign. Ultimately, next-generation vaccines would ideally help hold us for that full year.”

Currently, the original versions of the Pfizer/BioNTech, Moderna and Johnson & Johnson coronavirus vaccines are used in the United States — but vaccine makers have been working on updated versions of their vaccines.

‘Booster uptake so far isn’t that great’

Public health experts worry that there might be a sluggish uptake of any modified Covid-19 vaccines in the future.

“Our booster uptake so far isn’t that great, and so another booster is not going to necessarily cause people to run out and get the boosters they’ve already missed,” Freeman said.

About two-thirds of the US population — 67% — is fully vaccinated against Covid-19 with at least their initial series of vaccine, but less than a third — 32% — have received their booster, according to data from the CDC, as of Friday.

But that language and messaging around completing booster doses — and considering them as being up to date instead of as part of being fully vaccinated — “is not working,” said Dr. Peter Hotez, vaccine scientist and dean of the National School of Tropical Medicine at Baylor College of Medicine, told CNN. That is evident in the slow uptake of additional doses.

“Since the beginning of January 2021, I’ve said this was always a three-dose vaccine,” he said.

Now, people who have not yet completed their booster doses are becoming more vulnerable to Covid-19 infections, hospitalizations and deaths.

“There’s heavy consequences because we’re starting to see not only breakthrough hospitalizations, but even breakthrough deaths in people getting only two doses of the vaccine and not getting the booster — especially those over the age of 65 — so this is more than a theoretical discussion. Lives are being lost because of the messaging,” Hotez said.

At the moment, vaccine-induced protection against Covid-19 seems to not stay durable for as long as vaccine experts would hope, but it is not so clear why. Waning protection could be due to the vaccines themselves or due to the emergence of coronavirus variants evading the vaccines.

Hotez said that he thinks the White House should convene a panel of vaccine experts — outside of FDA’s VRBPAC — in a special meeting to determine whether the Covid-19 vaccine technology has a weakness when it comes to durability and what that means for future vaccine strategies.

“There’s two things happening at once. There could be waning immunity,” Hotez said, but at the same time, there have been variants like Delta and Omicron arriving on the scene.

“If all we had to worry about was Delta, would we be having a problem? Or would things have held up? And so I don’t know the answer to that,” Hotez said. “That’s why you want to convene the experts.”