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- After an afternoon of debate, an FDA panel voted Friday in favor of authorizing J&J's COVID-19 booster shot.
- The FDA has the final say in reviewing J&J's application to give an extra dose.
- A new study suggested Moderna's or Pfizer's vaccine also work as a booster for J&J recipients.
The Food and Drug Administration's expert panel voted Friday in support of Johnson & Johnson's application to offer a booster shot of its COVID-19 vaccine.
About 15 million people in the US have received the J&J single-dose vaccine, and Friday's positive recommendation clears a path for the agency to potentially authorize an extra dose those recipients. Unlike the Pfizer and Moderna booster shots, the FDA committee recommended all J&J recipients be offered a booster, regardless of age or risk of severe disease.
J&J is seeking to make a second dose available as early as two months after people got the first shot. The FDA's group voted unanimously, 19-0, in favor of recommending the additional shot.
The thumbs up comes despite limitations in J&J's booster data
The committee's blessing was not without debate. And the FDA is not required to follow the group's recommendations, although it typically does so.
On Wednesday, the FDA released its own summary of J&J's application that pointed out several key limitations in the evidence that J&J submitted for a booster shot. The FDA's review highlighted a lack of high-quality data supporting giving a booster six months following the first dose.
J&J submitted results from a study that included just 17 volunteers who got a second dose after six months. While that data appeared to meet the FDA's goals for what a booster should do, the FDA's review stated the results are limited by the small sample size and were also impacted by a subpar lab test J&J used.
There's far more evidence supporting a second dose of J&J given two months after the first shot. But that dataset, which includes more than 16,000 volunteers, has yet to be independently reviewed and verified by by FDA scientists.
Mixing-and-matching vaccine boosters could be more effective
New results from a mix-and-match booster study were released Wednesday showing that an mRNA booster shot after the J&J shot might lead to a better immune response compared to a second J&J booster.
That trial enrolled 458 people who had been vaccinated with either Pfizer's, Moderna's, or J&J's vaccine, then offered a boost of one of those three brands. J&J recipients saw a significantly larger jump in neutralizing antibody levels with a Moderna or Pfizer booster - respectively a 76-fold and 35-fold increase in antibodies - compared to another J&J shot, which yielded a 4-fold jump on average.
The FDA has been busy reviewing booster-shot applications from Moderna and Pfizer as well. The FDA's expert panel voted on Thursday to recommend Moderna's booster shot for authorization.
Pfizer's booster shot won emergency use authorization in August, with the FDA making a large swath of Pfizer recipients eligible for an extra dose after six months. This group includes the immunocompromised, people 65 years and older, and younger people at high risk of severe COVID-19.
The Centers for Disease Control and Prevention's expert panel is set to meet on October 20 and 21 to discuss the US booster policy.