The Food and Drug Administration is likely to authorize a third dose of Pfizer’s COVID-19 vaccine for all adults on Thursday. For some cities and states, the decision couldn’t come soon enough: An impatient and growing cadre of localities has already recommended third shots, before the FDA or the Centers for Disease Control and Prevention made a decision.
But not everyone thinks boosters across the board are a good idea. Among those issuing words of warning is one of the country’s leading vaccine development experts: Dr. Paul Offit, of Children’s Hospital of Philadelphia. For Offit, the issue is not that there are no benefits to the vaccine for younger people. It’s that there are also risks.
“You better have a very, very good reason for giving the booster dose, or else the risks will outweigh the benefits,” said Offit.
The particular risk Offit is concerned about is myocarditis, an immune response that causes inflammation of the heart.
Myocarditis is rare, but most common in young men ages 18 to 30. Symptoms can include chest pain, pressure or discomfort, shortness of breath, and palpitations. Traditional myocarditis can be treated with supportive care, such as oxygen or fluids, anti-inflammatory medicines, or in severe cases, with mechanical support or heart transplants.
It tends to be more common after the second dose of an mRNA vaccine, which can prompt a stronger immune response since the immune system is already “primed” to react. That has caused some scientists to be concerned that the risk for myocarditis could be even higher for a third shot. The reaction also seems to be more common with the Moderna vaccine, which is administered at a higher dose than Pfizer’s is.
As a result, a number of European countries, including France, Germany, Finland, and Sweden, are not administering the Moderna vaccine to those under 30 and pregnant individuals.
Offit sits on the FDA’s vaccine advisory committee, which did not recommend approving boosters for all adults for this very reason the last time Pfizer asked, back in September. Instead, the committee recommended boosters for people over 65 and younger adults with chronic medical conditions or whose jobs or living arrangements put them at high risk for COVID-19.
Last week, Pfizer again asked the FDA to authorize boosters for all remaining adults. It will not hear from the vaccine advisory committee this time, according to reporting from CNN.
Offit said the younger age group was left out of the earlier authorization because there wasn’t enough information about the frequency of myocarditis. Since the two-shot regimen is still highly protective against serious illness and death, and young healthy people are at lower risk for serious cases of COVID already, the FDA advisory panel wasn’t prepared to recommend that the group get a third dose.
“I think people would have been much more comfortable if the [age] was 35 or 40 in reference to boosting,” said Offit.
At least one thing is different about Pfizer’s petition for authorization this time around: The company has the results of a clinical trial that shows a third dose of its vaccine does indeed increase protection against symptomatic illness.
But that study didn’t offer a clear picture of the frequency of adverse side effects, specifically myocarditis.
Offit isn’t alone in his concern.
Dr. Walid Gellad, a professor of medicine at the University of Pittsburgh, pointed out that effectively anyone over 18 who wants a booster can get one already, since the high-risk category is somewhat subjective. So in essence, all Pfizer is requesting is official authorization for the very small remaining group of people who aren’t technically recommended to be vaccinated yet: younger adults without underlying conditions or dangerous jobs. For that group, the risk of serious cases of COVID is low and the risk of myocarditis, at least among men, is higher.
“It’s not about boosters in general, it’s about the specific group that you’re going to add to the authorization: young, healthy people who have no risk factors based on exposure to COVID,” said Gellad. ‘’Is the risk/benefit there for them?”
Even if the FDA and CDC end up making the same decision as the localities did in the long run, Gellad said that states and cities like New York City, California, Colorado, Arkansas, and New Mexico taking matters into their own hands sends a message that the regulatory process we have in place as a safeguard is not to be respected.
“If you constantly are saying, ‘Trust CDC to know what they’re doing, they know what they’re doing,’ and then you just decide to not follow them because of one thing you disagree with, well, I’m sure that doesn’t help with confidence in the CDC,” he said. “Those are not the kinds of decisions we leave to politicians.”
And, Gellad added, there hasn’t been much distinction between the types of shots in the recommendations coming from localities. While Pfizer is the one that asked for authorization, those who got the Moderna vaccine may walk into a pharmacy and ask for a booster of the same brand. Without the proper messaging and warning, that could be dangerous, he said.
President Joe Biden swore in August that his administration would have everyone boosted by the end of the year. Offit said he thinks that sent the wrong message.
“When President Biden stood up and said we’re going to have a third vaccine available for everyone in a month, what he also did was send the message that two doses wasn’t protective,” said Offit. “So now, a lot of people felt they weren’t protective so they rushed for the third dose.”
Though studies show that immunity from symptomatic and asymptomatic infection does wane after several months, protection against severe infection remains strong.
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