Many Americans who have been vaccinated against Covid-19 will soon be able to choose which vaccine they would like as a booster after the Food and Drug Administration issued emergency authorizations Wednesday that throws open the door to mixing and matching of vaccine brands.
In newly issued emergency use authorizations for the Moderna and Johnson & Johnson vaccines — and in a revision to the previous authorization of the Pfizer and BioNTech booster — the agency made clear that people do not have to get a third dose that matches their primary series.
“The available data suggest waning immunity in some populations who are fully vaccinated,” acting FDA Commissioner Janet Woodcock said in a statement. “The availability of these authorized boosters is important for continued protection against Covid-19 disease.”
Final approval of this booster strategy rests with the Centers for Disease Control and Prevention, which must sign off on this plan before it can become U.S. policy. The CDC’s expert panel on vaccines, the Advisory Committee on Immunization Practices (ACIP), meets to discuss the booster authorizations Thursday and will make recommendations to CDC Director Rochelle Walensky. Walensky’s signoff is needed to put the policy into play.
The authorizations will allow tens of millions of Americans to get Covid booster shots and — in a fundamental change of policy — effectively choose their booster. People in certain demographics who received the Pfizer-BioNTech vaccine six months ago or more have been able to seek a Pfizer booster since late September. But with authorization of the Moderna and J&J boosters, people who got those vaccines too can seek a booster if, in the case of the Moderna vaccine, six months have elapsed since their second shot, and in the case of the J&J, two months have gone by since they received the single J&J jab.
The move will also give states much needed flexibility for their vaccination rollouts, effectively allowing teams of vaccinators to bring one type of shot to a nursing home, for example, rather than requiring them to try to match booster jabs to the vaccine brand each resident initially received.
“We are also taking action today to include the use of mix and match boosters to address this public health need,” said Peter Marks, director of FDA’s Center for Biologics Evaluation and Research. “We will work to accrue additional data as quickly as possible to further assess the benefits and risks of the use of booster doses in additional populations and plan to update the healthcare community and public with our determination in the coming weeks.”
For people who initially received the Pfizer and Moderna shots, boosters are, for now, available only to people aged 65 and older, people aged 18 to 64 with health conditions that put them at high risk of developing severe illness if they catch Covid, and people aged 18 to 64 whose jobs or living circumstances put them at high risk of contracting Covid. The latter group includes health care workers and teachers, as well as people living in or working in homeless shelters and prisons.
Boosters are recommended for all of those who received the J&J vaccine, on the other hand.
The Biden administration had originally stated that boosters would be available for all vaccinated Americans; President Biden got his booster shot earlier this month. But the expert panels that advise the FDA and the CDC did not agree that the available evidence points to a need for boosters for healthy adults under the age of 65 at this point. Even with the restrictions they recommended, however, about 60% of people 18 to 64 meet the criteria for a booster at this point, Amanda Cohn, a CDC vaccines expert who sits on the FDA advisory committee, said last week.
Studies have suggested that using different types of vaccines could create a better and more long-lasting immune response. That appeared especially true with the J&J vaccine; following it up with a dose of one of the messenger RNA vaccines elicited substantially higher antibody levels, a study funded by the National Institutes of Health recently revealed.
But despite some discussion at a meeting last Friday of the FDA’s vaccines advisers, the Vaccines and Related Biological Products Advisory Committee (VRBPAC), the FDA did not stipulate that people who got the one-dose J&J vaccine should receive an mRNA shot rather than another J&J jab as a booster. Instead, the authorization suggested people who got the J&J shot can opt for a Moderna or Pfizer vaccine if they wish.
“A single booster dose of any of the available COVID-19 vaccines may be administered as a heterologous booster dose following completion of primary vaccination with a different available COVID-19 vaccine,” it said in a statement.
“For example, Janssen Covid-19 vaccine recipients 18 years of age and older may receive a single booster dose of Janssen COVID-19 Vaccine, Moderna Covid-19 vaccine (half dose) or Pfizer-BioNTech Covid-19 vaccine at least two months after receiving their Janssen Covid-19 vaccine primary vaccination,” the agency’s statement continued. “In another example, Moderna Covid-19 vaccine and Pfizer-BioNTech Covid-19 vaccine recipients … may receive a booster dose of Moderna Covid-19 vaccine (half dose), Pfizer-BioNTech Covid-19 vaccine or Janssen Covid-19 vaccine at least six months after completing their primary vaccination.”
Language added to the fact sheets provided to health care professionals about each vaccine say the shots “may be administered as a heterologous booster dose following completion of primary vaccination with another authorized or approved COVID-19 vaccine.” The language does not appear to offer any preference at all for having people receive a booster of their original vaccine.
It remains to be seen if the CDC — on the advice of the ACIP — turns that permissive recommendation into a preferential one, urging people who got the J&J vaccine to get an mRNA dose as their booster shot. The committee has been concerned for some time about the situation people who got the J&J’s one-and-done vaccine find themselves in, given that the vaccine is less effective than the mRNA vaccines at protecting against Covid infection.