The Food and Drug Administration has authorized a fourth dose, or second booster shot, of the Pfizer and Moderna COVID-19 vaccines for adults age 50 and older and immunocompromised groups.
The announcement on Tuesday comes as a more transmissible Omicron subvariant known as BA.2, which is driving new COVID-19 surges in China, the U.K. and other European countries, has become dominant in the U.S., according to Centers for Disease Control and Prevention data. BA.2 now accounts for about 55% of new coronavirus cases nationwide, according to the agency.
Dr. Peter Marks, who oversees the FDA’s vaccine division, said current evidence suggests that protection against serious outcomes from COVID-19 in older and immunocompromised individuals wanes over time. “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,” he said in a statement.
The FDA added that “the known and potential benefits of a second COVID-19 vaccine booster dose with either of these vaccines outweigh their known and potential risks in these populations.”
Based on the FDA decision, a second booster of the Pfizer-BioNTech or Moderna vaccines “may be administered to individuals 50 years of age and older at least 4 months after receipt of a first booster dose of any authorized or approved COVID-19 vaccine.”
People 12 and older with certain kinds of autoimmune disorders, such as those who have undergone organ transplants, will also be eligible for a second booster dose of the Pfizer shot, the FDA said, while those 18 and older who are immunocompromised can pick between Pfizer’s and Moderna’s.
The updated emergency use authorization is based in part on recent real-world studies from Israel, which have shown that a fourth shot had a meaningful impact for older adults. One of the studies in particular showed that senior citizens who received a second booster of the Pfizer vaccine had a 78% reduction in mortality rate from the disease compared with those who got only one booster.
“The good news about this announcement is that it allows people who most need a booster shot to get it. The bad news is that without clearer messaging on exactly which patients and populations benefit the most from a booster shot (because not everyone derives the same benefit), we risk boosting low-risk populations and widening equity gaps. We also risk raising people’s expectations of what a booster can and cannot do,” said Dr. Lucy McBride, a Yahoo News medical contributor.
Just a few hours after the Tuesday announcement, the CDC revised its COVID-19 vaccine recommendation to match the FDA authorization. The agency also said adults who received the one-dose Johnson & Johnson primary series and had received a booster at least four months ago could get a second booster using one of the two mRNA COVID-19 vaccines available.
These additional doses are expected to become available immediately. However, according to the Associated Press, health officials framed the second booster as an option that could offer older adults and vulnerable people an additional layer of protection, but they did not urge everyone who is now eligible to rush out and get the shots immediately.
“The decision on when and if to get a booster shot depends on people’s age, underlying medical conditions, immunity to COVID, and the social determinants of their health — which is exactly why now, more than ever, people need unfettered access to a trusted primary care medical guide,” said McBride.
The FDA’s endorsement of a second booster dose was made without the typical vote of the agency’s outside experts, the Vaccines and Related Biological Products Advisory Committee.
“It’s quite unusual for the FDA to bypass the voting process. I just hope this doesn’t erode confidence in the vaccines,” McBride told Yahoo News.
The independent experts on the advisory committee are scheduled to meet on April 6 to discuss the additional booster shots. Representatives from the CDC and the National Institutes of Health will also participate in the meeting, the FDA said.