FDA authorizes Moderna and J&J Covid vaccine boosters, permits ‘mix and match’
Booster shots are now permitted for all three of the Covid-19 vaccines currently authorized, and those eligible will be able to choose. The FDA has amended the emergency authorizations for the Moderna and Johnson & Johnson vaccines to include boosters, a decision that was expected following the unanimous recommendations of the agency’s advisory panel last week. But the agency went further in its Wednesday evening announcement and said a booster can be different than the one received in the initial vaccination—what’s sometimes called “mix and match.”
For the Moderna vaccine, boosters are now authorized for those 65 and older, adults between 18 and 64 who are at high risk of severe Covid-19, and those in that same age group whose jobs put them at risk of exposure to the novel coronavirus. The Moderna booster is authorized as a single shot six months after a person has completed the initial two-shot regimen. That booster is half the dose of a shot in the initial vaccination series.
The changes for the J&J vaccine, which was initially authorized as a single shot, are different. The FDA said those vaccinated with a J&J shot may get a booster two months after the initial shot. That amendment to the J&J authorization covers all J&J vaccine recipients 18 and older.
The FDA authorized booster shots for the Pfizer/BioNTech Covid vaccine in September, an amendment that permitted these shots for older Americans and those at high risk of infection. On Wednesday, the FDA clarified that authorization of this single dose booster, given at least six months after the initial two-shot regimen, includes those 18 to 64 whose jobs expose them to SARS-CoV-2.
Janet Woodcock, the FDA’s acting commissioner, said that boosters are needed to maintain protection against the virus.
“As the pandemic continues to impact the country, science has shown that vaccination continues to be the safest and most effective way to prevent COVID-19, including the most serious consequences of the disease, such as hospitalization and death,” Woodcock said in a prepared statement. “The available data suggest waning immunity in some populations who are fully vaccinated. The availability of these authorized boosters is important for continued protection against COVID-19 disease.”
The National Institutes of Health has been conducting mix and match studies to assess the potential risks and benefits. Some of the initial findings were presented to the FDA advisory panel last week. The study is open label and is not designed to compare the boosters to each other. But the early results look encouraging. “Heterologous boosts,” or boosting with a vaccine that’s different than the one from the primary immunization, resulted in similar or even higher immune responses compared to a same-shot booster. Also encouraging was that no safety concerns emerged.
The advisory committee discussed mixing and matching of vaccines, but that topic was not brought to a vote. In its announcement of the changes to the vaccine authorizations, the FDA said its assessment of mixing and matching considered the NIH presentation, the advisory committee’s discussion, and the agency’s own evaluation of the available data. The FDA said it determined that the benefits of a single heterologous booster outweigh the potential risks.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in the announcement that the FDA is working to gather more data to assess the risks and benefits of boosters in additional groups of people. He added that he expects the agency will be able to provide an update “in coming weeks.” But the emergency use authorization changes announced Wednesday are now set to be discussed Thursday by an advisory committee to the Centers for Disease Control and Prevention. Based on that discussion the CDC will issue its own recommendations about how boosters should be used.
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