As expected, the Food and Drug Administration on Wednesday authorized second-generation COVID-19 boosters from Moderna and Pfizer-BioNTech. The newly authorized boosters are bivalent, targeting both the original strain of SARS-CoV-2 and the BA.4/5 omicron subvariants, which share the same spike protein and are currently the dominant variants circulating.
The new Pfizer-BioNTech boosters—which the FDA calls “updated boosters”—will be available to everyone 12 and above. The updated Moderna boosters will be available to anyone 18 and up. In both cases, the boosters should be given at least two months after the last COVID-19 vaccine or booster.
The FDA’s authorization comes ahead of a scheduled meeting Thursday and Friday of an advisory panel for the Centers for Disease Control and Prevention. The CDC panel of independent expert advisors—the Advisory Committee on Immunization Practices (ACIP)—will vote on whether the updated boosters should be recommended for use as early as Thursday.
If the committee votes in favor and CDC director Rochelle Walensky endorses the recommendation, the boosters will then become available to the public. It is anticipated that the recommendation will go through. The Biden administration has for weeks signaled that it expects the fall booster campaign with these second-generation boosters would begin around Labor Day. States have already been able to preorder doses of the updated boosters, and shipments can begin now that the FDA has issued the authorization.
In a press briefing Wednesday, FDA Commissioner Robert Califf emphasized the need for fall boosters, noting that the country is still seeing more than 400 deaths every day from COVID-19 and over 5,000 new hospitalizations daily. In addition, he also referenced provisional CDC data released Tuesday suggesting Americans’ life expectancy fell yet again in 2021, largely due to COVID-19 deaths. The life expectancy for Americans born in 2021 is just 76.1 years, a 2.7-year drop since 2019, before the pandemic.
“The COVID-19 vaccines, including boosters, continue to save countless lives and prevent the most serious outcomes (hospitalization and death) of COVID-19,” Califf said in a statement. “As we head into fall and begin to spend more time indoors, we strongly encourage anyone who is eligible to consider receiving a booster dose with a bivalent COVID-19 vaccine to provide better protection against currently circulating variants.”
While the argument for fall boosters is straightforward, the design for the updated boosters has been more complicated. COVID-19 vaccine makers Moderna and Pfizer-BioNTech had a sizeable amount of data, including clinical data, on the safety and efficacy of an updated booster that targeted the original omicron stain, BA.1. They have yet to collect clinical data on the BA.4/5-targeting boosters.
However, the FDA “very deliberately” decided to go after the most current omicron subvariants, BA.4 and BA.5, rather than BA.1, which is no longer circulating, FDA’s top vaccine regulator Peter Marks said Wednesday. In June, a panel of FDA advisors voted 19 to 2 in favor of redesigning boosters to be bivalent and target omicron. The committee largely expresses support for targeting BA.4/5, specifically. The BA.5 subvariant currently accounts for about 89 percent of US cases. Marks argued that the preliminary and observational data on BA.4/5-targeting immune responses seemed to offer more protection than seen with BA.1. In addition, the agency reasoned that boosting against the latest variant could position people to be better protected from whatever comes next.
Marks also addressed concern about the lack of clinical data so far, comparing the COVID booster authorization process to the process of updating annual flu vaccines. “We’ve had extensive experience in the past with strain changes made without clinical data based on the totality of available evidence. This is the case with influenza vaccine for which such strain changes are made safely and effectively every year,” Marks said. “Based on the [COVID-19-related] data, the updated boosters are expected to provide increased protection against the currently circulating omicron variant.”
In statements Wednesday, Moderna and Pfizer-BioNTech celebrated the authorizations.
“Receiving a booster that specifically targets the Omicron BA.4/.5 variant, currently the most prevalent strain of SARS-CoV-2, is an important public health measure that people can take to help protect themselves, especially as we head into a season filled with indoor gatherings,” Moderna CEO Stéphane Bancel said. “We are grateful to the FDA for their decisive leadership.”
Pfizer CEO Albert Bourla said the companies were “thrilled” by the FDA’s decision. “As we head into the fall and winter season, with the potential for greater SARS-CoV-2 spread in schools and at work, it is important to stay up to date with vaccines as a first line of defense against COVID-19 illness.”