Food and Drug Administration advisers will meet Thursday to discuss simplifying the Covid vaccination schedule, allowing most people to get the currently available booster, regardless of how many doses they had received before that.
The agency's proposal was outlined in briefing documents posted online Monday.
Currently, everyone ages 6 months and older are required to complete a primary vaccination series — at least two doses of either the Pfizer-BioNTech, Moderna or Novavax vaccines or a single dose of the Johnson & Johnson vaccine— before they can get a booster dose two months later.
The FDA is proposing skipping over that primary series, meaning that most unvaccinated individuals could go ahead and get the latest booster shot if they decided to get a Covid vaccine.
Some groups, however, would still be advised to get two doses, according to the briefing documents. They include older adults, immunocompromised people and children 2 years old and younger.
The FDA’s proposal, experts say, would greatly simplify the Covid vaccination schedule in the U.S. — aligning it more closely with the annual flu shot.
In another similarity to the flu shot, the FDA is considering whether the Covid vaccine should be updated at least once a year, based on what strains are in circulation.
The agency’s proposals will be put before its Vaccines and Related Biological Products Advisory Committee on Thursday.
The committee will also discuss whether the primary series should be changed to the updated bivalent formula used in the new booster shots. Those shots, authorized in the fall, protect against the omicron subvariants BA.4 and BA.5, in addition to the original strain of the coronavirus that was identified in Wuhan, China, in late 2019. The vaccines used in the primary series are only targeted to the original strain.
Dr. Anna Durbin, a vaccine researcher at Johns Hopkins University in Baltimore, said simplifying the Covid vaccine schedule makes sense.
Multiple formulas and vaccination schedules, she said, may complicate vaccine administration for pharmacists and also may discourage people from getting vaccinated at all.
Some patients, Durbin noted, have said they've had trouble finding pharmacies that still carry the original formulation of the vaccines — meaning they were unable to get their primary series.
Dr. Isaac Bogoch, an infectious disease specialist at the University of Toronto, said the FDA’s proposal moving away from the primary series is “reasonable,” noting that most people have some form of immunity from a prior Covid infection even if they haven't yet been vaccinated.
“From a human behavior standpoint, people who have not received the primary series with the vaccine at this point in time are probably not going to receive it,” he said. “You might get better uptake if you say, ‘Listen, here’s a booster. Here’s one shot.”