Who needs a second dose?
On Oct. 14, the committee heard an update on data from Israel, which saw a wave of severe breakthrough infections during the Delta wave.
COVID-19 cases are falling rapidly there after the country widely deployed booster doses of the Pfizer vaccine.
The FDA’s Dr. Marks said Oct. 15 that the agency was leaning toward creating greater flexibility in the emergency use authorizations (EUAs) for the Johnson & Johnson and Moderna vaccines so that boosters could be more widely deployed in the United States too.
The FDA panel on Oct. 14 voted to authorize a 50-milligram dose of Moderna’s vaccine — half the dose used in the primary series of shots — to boost immunity at least 6 months after the second dose.
Those who might need a Moderna booster are the same groups who’ve gotten a green light for third Pfizer doses, including people over 65, adults at higher risk for severe COVID-19, and those who are at higher risk because of where they live or work.
The FDA asked the committee on Oct. 15 to discuss whether boosters should be offered to younger adults, even those without underlying health conditions.
“We’re concerned that what was seen in Israel could be seen here,” Dr. Marks said. “We don’t want to have a wave of severe COVID-19 before we deploy boosters.”
Trying to avoid confusion
Some members of the committee cautioned Dr. Marks to be careful when expanding the EUAs, because it could confuse people.
“When we say immunity is waning, what are the implications of that?” said Michael Kurilla, MD, PhD, director of the division of clinical innovation at the National Institutes of Health.
Overall, data show that all the vaccines currently being used in the United States — including Johnson & Johnson — remain highly effective for preventing severe outcomes from COVID-19, like hospitalization and death.
Booster doses could prevent more people from even getting mild or moderate symptoms from “breakthrough” COVID-19 cases, which began to rise during the recent Delta surge. The additional doses are also expected to prevent severe outcomes like hospitalization in older adults and those with underlying health conditions.
“I think we need to be clear when we say waning immunity and we need to do something about that, I think we need to be clear what we’re really targeting [with boosters] in terms of clinical impact we expect to have,” Dr. Kurilla said.
Others pointed out that preventing even mild-to-moderate infections was a worthy goal, especially considering the implications of long-haul COVID-19.
“COVID does have tremendous downstream effects, even in those who are not hospitalized. Whenever we can prevent significant morbidity in a population, there are advantages to that,” said Steven Pergam, MD, MPH, medical director of infection prevention at the Seattle Cancer Care Alliance.
“I’d really be in the camp that would be moving towards a younger age range for allowing boosters,” he said.
This article was updated on 10/18/21. A version of this article first appeared on.