Emergency use authorization was granted Wednesday by the Food and Drug Administration for a third dose of Pfizer and BioNTech’s COVID-19 vaccine to be given to three groups — those 65 and older, those at high risk of developing severe COVID-19 and those at risk of developing “serious complications” due to “frequent institutional or occupational exposure,” likely including frontline health care workers and those in prisons. The authorization makes the Biden administration’s plan to roll out booster shots this week at least partially possible.
“After considering the totality of the available scientific evidence and the deliberations of our advisory committee of independent, external experts, the FDA amended the EUA for the Pfizer-BioNTech COVID-19 Vaccine to allow for a booster dose in certain populations such as health care workers, teachers and day care staff, grocery workers and those in homeless shelters or prisons, among others,” acting FDA Commissioner Janet Woodcock said in a statement.
However, under federal agreements governing use of the shots, most vaccine providers will still need to wait for a committee of vaccine advisers from the Centers for Disease Control and Prevention to formally recommend the third dose.
The CDC Advisory Committee on Immunization Practices, met Wednesday to discuss the potential use of Pfizer’s booster shots. It reviewed safety data collected from the millions of Americans who have already received additional doses of vaccine.
The committee previously discussed prioritizing booster doses for those at highest risk of severe so-called “breakthrough” infections and essential frontline workers like doctors and nurses, where even outbreaks of mild cases of COVID-19 can sideline fully vaccinated providers and cripple hospitals. They are expected to vote Thursday on its own guidelines for use of the shots.
On Wednesday, the CDC presented new data to the ACIP highlighting decreasing vaccine effectiveness against symptomatic infection with the onslaught of the Delta variant, and potentially against severe COVID-19 among older adults. A CDC scientist also presented modeling suggesting that booster shots could help curb cases in nursing homes, but cautioned that vaccinating seniors alone may only result in a “small to moderate” effect on curbing the pandemic’s spread overall.
The third dose of Pfizer’s vaccine has not presented any safety concerns among those who have received one so far, CDC officials said. Around 2.3 million Americans have received an additional dose since authorities first allowed them for some immunocompromised people.
The agency also released several studies suggesting vaccine effectiveness against infection and hospitalization has declined for many adults, though rates of COVID-19 remain far higher among unvaccinated Americans. A CDC investigation into a Delta variant outbreak at a federal prison in Texas was released Tuesday. It underscored the risk of breakthrough infections in crowded settings, with 70% of fully vaccinated inmates testing positive for the virus.