Second COVID Booster Gets OK for Some, Despite Limited Evidence It's Needed

The Food and Drug Administration (FDA) approved a second COVID-19 booster dose for those age 50 and up on Tuesday.

The decision applies to both the Pfizer and Moderna vaccines. However, with COVID-19 cases still relatively low in the United States, there is "limited evidence" to indicate how much another booster would help, as Centers for Disease Control and Prevention (CDC) data indicates that two doses and a booster still provide strong protection against severe infections and death, the Associated Press reported.

COVID-19 cases in the U.S. have been low, with data from Reuters showing cases are currently only at 4 percent of their peak from the beginning of this year, when the Omicron variant led a large spike in cases. However, there are still worries that the BA.2 sub-variant of Omicron could lead to another spike in cases, a trend that has already been seen in some European countries like France, the U.K. and Italy.

The FDA recommends people 50 and older receive their second booster at least four months after receiving the first one, according to a news release from the agency. It has also approved the fourth dose for those 18 and older who have "certain kinds of immunocompromise" and those 12 and older "who have undergone solid organ transplantation, or who are living with conditions that are considered to have an equivalent level of immunocompromise."

The release said that when evaluating this decision, the FDA analyzed the "safety and immune response information" provided to the agency as well as information on the vaccines' effectiveness from the companies making them. Israel's Ministry of Health also provided the FDA with data on about 700,000 fourth doses given at least four months after the third doses, which "revealed no new safety concerns."

The release also cited a study of Israeli health care workers who received the fourth dose that found an increase in antibody levels two weeks after the second booster dose that were comparable to the levels found five months after the first booster dose.

Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, said in the release that the data shows the second dose could help those with higher risk of getting the virus.

"Current evidence suggests some waning of protection over time against serious outcomes from COVID-19 in older and immunocompromised individuals," Marks said. "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 also encouraged all who had not yet gotten their first booster dose to get it, saying it is "critical in helping to protect all adults from the potentially severe outcomes of COVID-19."

Update 03/29/22 12:35 p.m. ET: This story was updated to add more information and background.

FDA Approves Another COVID-19 Booster
The FDA approved another COVID-19 booster for those 50 and up. Above, a health worker prepares the Pfizer COVID-19 vaccine on March 22 in San Salvador, El Salvador. Photo by Emerson Flores/APHOTOGRAFIA/Getty Images