U.S. regulators cleared second booster doses of COVID-19 vaccine from Moderna Inc. and the partnership of Pfizer Inc. and BioNTech SE for adults 50 and older, making millions more people eligible for the shots as concern grows about a potential new wave of infections.
Those who have received a first booster dose of the drugmakers’ shots at least four months earlier can now get another, the Food and Drug Administration said Tuesday. For most people, the second booster will be a fourth shot, while it will be the third for those who got initial single-shot immunizations from Johnson & Johnson.
While highly transmissible omicron has declined overall, the virus’s BA.2 strain continues to spread, leading to concerns about a resurgence and the need for additional safeguards. In many countries in Europe, cases remain at very high levels thanks to this even more-transmissible subvariant. Booster doses are becoming an increasingly relied-upon tool in the fight against COVID-19, especially as states and companies cut back safeguards such as masking and work from home.
“Current evidence suggests some waning of protection over time against serious outcomes from COVID-19 in older and immunocompromised individuals,” Peter Marks, who leads the FDA center that oversees vaccines, said in a statement. “Based on an analysis of emerging data, a second booster dose of either the Pfizer-BioNTech or Moderna COVID-19 vaccine could help increase protection levels for these higher-risk individuals.”
Meanwhile, the Biden administration is warning that funding is needed to continue fighting the virus. The U.S. lacks sufficient supplies to give everyone an additional booster dose of mRNA vaccine if regulators open up eligibility more widely,, officials have said.
The FDA also authorized a second booster dose of Pfizer-BioNTech vaccine for certain immunocompromised people 12 and older, and Moderna’s vaccine for a similar population 18 and older. That additional shot can be administered at least four months after the receipt of a first authorized booster dose. People ages 12 and older with moderately or severely compromised immune systems were already able to get four shots, three of which counted as their primary series.
It’s not clear how significant the uptake will be for fourth-dose boosters, given that cases are low in the U.S. and deaths are declining. By contrast, some other countries like Israel that gave fourth doses to older people rolled them out at the height of the omicron wave.
In the U.S., the second booster dose is expected to be rolled out with much less fanfare than the first. The Centers for Disease Control and Prevention isn’t planning to convene a meeting of a panel of outside advisers who make vaccine use recommendations, as it did with the first rounds of COVID shots, according to U.S. officials familiar with the situation.
The CDC didn’t immediately respond to a request for comment. The White House declined to comment.
This second booster may not be the last one. The virus is expected to continue to mutate, raising the likelihood that the vaccine will eventually need to be updated to fight new strains. Both Pfizer and Moderna are working on omicron-specific boosters, as well as shots that would combine the existing vaccine with an omicron-specific formulation. Data from those trials could start to arrive in the coming weeks.
With no clear consensus on future boosters, the FDA is planning a meeting of outside advisers on April 6 to assess broad questions of when additional COVID boosters should be given and when shots should be updated to address new variants.
