FDA's top vaccine leader explains why Covid-19 'boosters' may really just be the 3rd shot in the primary series
Don’t call it a booster. Well, call it a booster for a little while longer but then we’ll just say it’s the third dose of a three-dose vaccine, according to FDA’s top vaccine leader Peter Marks.
Speaking on a stakeholder call with physician groups earlier this week, Marks explained how fluid the situation is with terminology, after a representative from the American Academy of Family Physicians said there’s confusion around whether what the FDA authorized last week is actually a booster or the third dose in this initial series of Covid-19 vaccine shots.
“This is again something in a time of transition,” Marks said in response. “Honestly, the reason why we’ve sometimes called them third doses is because the third dose is being given at six months and may indeed be the third dose of a primary series. It may be that after this pandemic is over, much like the hepatitis B vaccine or the hepatitis A vaccine or other adult vaccinations, there will be three doses at 0, 1, and 6 months.”
He also said that the FDA is currently calling this third shot a booster so as not to alarm the general public about not being fully vaccinated.
“Just to be totally transparent, the reason for calling it a booster and not the third dose of a primary series, is that we actually don’t want to alarm the entire population by suddenly telling them that they’re no longer completely vaccinated with a three dose series. So it’s a booster for now and ultimately we may transition into calling it a three dose series,” Marks said.
But he told physician groups that in order to stay on the same page, they should stick with calling these third shots boosters because that’s what they’re called on the label, and that’s what people understand. For those who are immunocompromised, “we can call them third doses,” he added, while noting that it may turn out that immunocompromised people may need additional boosting.
Janet Woodcock, acting commissioner of the FDA, also noted that in some immunocompromised people, that additional boost may not work.
“You may be able to give them numerous vaccinations and they don’t respond, and that’s where we will be looking at pre-exposure prophylaxis and treatment with monoclonals and maybe some antivirals on the horizon,” Woodcock added.
The comments follow a tumultuous few weeks of figuring out who exactly should be the first to receive the boosters (or third doses). The FDA gave the expanded EUA for the Pfizer/BioNTech booster shot last week for a more narrow population than the companies initially wanted.