Booster confusion
The April 6 FDA meeting of the agency’s Vaccines and Related Biological Products Advisory Committee comes as the two major COVID vaccine makers — Pfizer and Moderna — have applied for emergency use authorization for an additional booster.
Pfizer had asked for authorization for a fourth shot in patients over age 65 years, while Moderna wanted a booster to be available to all Americans over 18. The FDA instead granted authorization to both companies for those over 50 and anyone 18 or older who is immunocompromised.
What this means for the committee’s April 6 meeting is not clear. The original agenda says the committee will consider the evidence on safety and effectiveness of the additional vaccine doses and discuss how to set up a process — similar to that used for the influenza vaccine — to be able to determine the makeup of COVID vaccines as new variants emerge. That could lay the groundwork for an annual COVID shot, if needed.
The FDA advisers will not make recommendations nor vote on whether — and which — Americans should get a COVID booster. That is the job of the CDC’s Advisory Committee on Immunization Practices (ACIP).
The last time a booster was considered, CDC Director Rochelle Walensky, MD, overrode the committee and recommended that all Americans — not just older individuals — get an additional COVID shot, which became the first booster.
That past action worries Dr. Gandhi, who calls it confusing, and says it may have contributed to the fact that less than half of Americans have since chosen to get a booster.
Dr. Schaffner says he expects the FDA to authorize emergency use for fourth doses of the Pfizer and Moderna vaccines, but he doesn’t think the CDC committee will recommend routine use. As was seen before, however, the CDC director does not have to follow the committee’s advice.
The members of ACIP “might be more conservative or narrower in scope in terms of recommending who needs to be boosted and when boosting is appropriate,” Dr. Kuritzkes says.
Dr. Gandhi says she’s concerned the FDA’s deliberations could be swayed by Moderna and Pfizer’s influence and that “pharmaceutical companies are going to have more of a say than they should in the scientific process.”
There are similar worries for Dr. Schaffner. He says he’s “a bit grumpy” that the vaccine makers have been using press releases to argue for boosters.
“Press releases are no way to make vaccine recommendations,” Dr. Schaffner said, adding that he “would advise [vaccine makers] to sit down and be quiet and let the FDA and CDC advisory committee do their thing.”
Moderna Chief Medical Officer Paul Burton, MD, however, told WebMD last week that the signs point to why a fourth shot may be needed.
“We see waning of effectiveness, antibody levels come down, and certainly effectiveness against Omicron comes down in 3 to 6 months,” Burton said. “The natural history, from what we’re seeing around the world, is that BA.2 is definitely here, it’s highly transmissible, and I think we are going to get an additional wave of BA.2 here in the United States.”
Another wave is coming, he said, and “I think there will be waning of effectiveness. We need to be prepared for that, so that’s why we need the fourth dose.”