The FDA has authorized a booster dose of Moderna's COVID-19 vaccine, allowing it to play catch up with the Pfizer-BioNTech shot, which scored a booster approval last month.
The agency also blessed a second dose of the Johnson & Johnson vaccine. That nod applies to adults who have received one J&J shot two months prior.
“The currently available data suggest waning immunity in some populations of fully vaccinated people,” FDA acting commissioner Janet Woodcock told reporters on Wednesday night. “The availability of these authorized boosters is important for continued protection against COVID-19.”
Additionally, the regulator signed off on the "mix-and-match" approach for the three U.S.-licensed COVID-19 vaccines, allowing Americans to receive a booster shot that differs from their original vaccine.
As far as user preference is concerned, the nods are likely to put more distance between the J&J vaccine and the mRNA shots produced by Moderna and Pfizer, which have been shown to provide a stronger immune response as a booster for previous J&J recipients.
Like the Pfizer endorsement, the Moderna nod covers those 65 and older and others who are at high risk because of preexisting conditions or occupations that make them more susceptible to exposure. The Moderna booster approval is for a dose half the size of its original version.
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The booster approval for J&J, just two months following initial vaccination, was deemed necessary because the shot has shown a lower level of effectiveness, officials said.
Allowing booster use across the three vaccines will allow providers to manage their stocks more efficiently.
“Being able to interchange these vaccines is a good thing. It’s like what we do with flu vaccines,” Peter Marks, the director of the FDA’s Center for Biologics Evaluation and Research, told reporters. “Many people don’t know what brand of flu vaccine they received.”
Looking forward, the FDA's vaccine reviewers will stay busy over the next several weeks as they consider whether to expand approvals of the vaccines to children and when to open booster use to those under age 65. On Tuesday, an FDA advisory committee will decide whether to recommend the Pfizer shot for use in kids between the ages of 5 and 11.
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Also on the table is a request from Moderna to approve its vaccine in children ages 12 to 17. The FDA has delayed that decision because of rare cases of myocarditis, The Wall Street Journal reported earlier this week. Four Nordic countries have suspended use of the Moderna vaccine in those younger than 30.