FDA Officials Push Back After Adviser Says Young, Healthy People Don’t Need New COVID-19 Boosters

Food and Drug Administration Commissioner Robert Califf speaks to members of Congress in Washington on June 16, 2022. Joe Raedle/Getty Images

Top U.S. Food and Drug Administration (FDA) officials are countering an adviser’s position that young, healthy people do not need the updated COVID-19 vaccine boosters.

Drs. Robert Califf and Peter Marks pointed to a study that analyzed the immune response from 12 people after receiving one of the updated boosters, compared with 23 people who received one or more old boosters. The paper found a small increase in neutralizing antibodies, which are believed to protect against COVID-19.

They also referenced three studies published in the Morbidity and Mortality Weekly Report, a quasi-journal from the U.S. Centers for Disease Control and Prevention (CDC). The three papers, published in December 2022 and relying on observational data, found the new boosters bolster effectiveness against symptomatic infection and/or hospitalization. They did not reference newer CDC data that indicates the protection quickly wanes.

“Given the excellent safety profile of the vaccines, which is similar to that of the influenza vaccine among persons 6 months of age or older, the totality of the available evidence supports the vaccination of all currently eligible persons with updated Covid-19 vaccines as an important public health intervention,” Califf, the FDA’s commissioner, and Marks, its top vaccine official, claimed in a March 1 letter published by the New England Journal of Medicine.

They were responding to Dr. Paul Offit, one of the FDA’s vaccine advisers.

Offit wrote in the same journal in January that “we should stop trying to prevent all symptomatic infections in healthy, young people by boosting them with vaccines containing mRNA from strains that might disappear a few months later.”

The Pfizer and Moderna vaccines utilize messenger RNA (mRNA) technology. Updated versions of the vaccines, which contain components of the Wuhan variant and Omicron subvariants BA. 4 and BA.5, were authorized by the FDA and recommended by the CDC in the fall of 2022 despite no clinical trial data being available. The FDA did not respond when asked if, six months later, it has received any trial data yet.

Offit pointed to several preprint papers that found the updated vaccines did not elicit strong immune responses, which Offit said was likely due to immune imprinting because of how the vaccines still contain the Wuhan component. He said that the bivalent strategy had “fail[ed],” that the “moderate increase in protection” would be “short lived” and that “booster dosing is probably best reserved for the people most likely to need protection against severe disease.”

President Joe Biden receives a bivalent COVID-19 booster shot in the South Court Auditorium of the Eisenhower Executive Office Building, next to the White House, in Washington on Oct. 25, 2022. Saul Loeb/AFP via Getty Images

‘Should Be Targeted’

In a March 1 reply to the FDA officials, Offit noted that the study Marks and Califf referenced showed that a bivalent vaccine, compared with a monovalent booster, caused an increase in neutralizing antibodies of 1.5 times against BA.1.1, an Omicron subvariant, and 2.6 times against XBB.1, another subvariant, which has become dominant in the United States in recent weeks.

“Neither of these increases, however, is likely to be clinically significant,” Offit said.

While Marks and Califf “correctly note that bivalent boosters have enhanced protection against symptomatic disease in 18-to-49-year-olds, at least in the short term,” none of the papers estimated protection against hospitalization along among people younger than 65, Offit noted. One of the studies estimated effectiveness of a bivalent in adults against hospitalizations, emergency room visits, and urgent care encounters as 57 percent after seven or more days. Newer data, unmentioned by Califf and Marks, found protection was 55 percent seven or more days after a bivalent, but quickly dropped to under 50 percent.

Offit said the goal of the vaccines, which are authorized to prevent COVID-19 disease, is to protect against hospitalization and that booster administration “should be targeted to the groups most likely to be hospitalized—specifically, persons who are elderly or immunocompromised, have multiple coexisting conditions, or are pregnant.”

A nurse holds a syringe that contains a dose of the Pfizer COVID-19 vaccine in Seattle, Wash., on June 21, 2022. David Ryder/Getty Images

‘Dishonest Statements’

Dr. Vinay Prasad, a professor at the University of California, San Francisco’s Department of Epidemiology and Biostatistics, said the statements made by Califf and Marks were dishonest.

Their letter “argues— falsely—that good evidence shows boosters benefit young people,” Prasad wrote.

The immunogenicity study shows only a small increase that is unlikely to be meaningful, Prasad side, echoing Offit.

He also panned the reliance on studies in the CDC’s quasi-journal, which only publishes papers after they’ve been reviewed by top officials at the agency, which has been aggressively promotive of the COVID-19 vaccines.

“None are randomized trials. All have biases, including unmeasured confounding,” Prasad said. “One study is only >65 years old and up, which is not the topic of debate. One is a criminally stupid study that compares bivalent boosters to a group that includes people who got the original 2 doses but no 3rd dose. But bivalent boosters are nearly exclusively given to people who got 2 original doses AND a 3rd dose.”

The FDA officials also said that the safety profile of the vaccines is “excellent,” but healthy, young people—especially young males—are at risk of heart inflammation from the shots, Prasad noted, adding that the inflammation is not a concern with the influenza vaccine.

“This letter is emblematic of the FDA’s caliber of analysis—very poor quality analyses used to push conclusions for policy decision it has already reached,” he said.