Mirroring a similar recommendation issued last month for the Pfizer COVID-19 vaccine, an expert advisory panel to the U.S. Food and Drug Administration on Thursday recommended a half-dose booster shot of the Moderna vaccine be given to certain recipients six months after their second shot.
Panelists recommended that everyone aged 65 or older who received the two-dose Moderna regimen get a third dose, as well as any younger adult who might be at high risk for COVID-19 due to a medical condition or a job that increases their exposure to SARS-CoV-2, The New York Times reports.
What the data shows
The data presented was not particularly decisive, committee members say, but they note that a precedent had been set in September when the FDA gave emergency authorization to booster shots for the millions of Americans who’d gotten the Pfizer-BioNTech vaccine.
The evidence of a need for booster shots was clearer for the Pfizer vaccine, however.
In data presented to the panelists last month, one study from the U.S. Centers for Disease Control and Prevention found that four months after a person’s second dose of the Pfizer vaccine, its effectiveness in preventing illness requiring hospitalization fell from 91% to 77%.
But with the Moderna vaccine, the drop-off over time was much less dramatic, making the justification for any booster shot much weaker.
Acknowledging that, Moderna argued instead that a booster could still be useful in preventing mild or moderate forms of COVID-19.
As part of the data presented, Moderna says its study found that