This story has been updated. 

Sept. 11, 2023 – The FDA today authorized the newest COVID-19 vaccine, the first not to target the initial or “ancestral” strain of the virus. 

Last year, the FDA authorized a bivalent vaccine aimed at both the old and the new. This time, it’s a “monovalent” or single-strain vaccine with one main objective: to minimize health risks, hospitalizations, and deaths associated with newer variants like the XBB.1.5 Omicron subvariant. It is also expected to provide some protection against related variants currently in circulation

The FDA authorization applies to vaccines made by both Pfizer and Moderna. 

So what does ‘some protection’ mean? “It’s hard to say with the information I’m seeing released so far,” said Beverly Sha, MD, professor of medicine, Division of Infectious Diseases, RUSH University Medical College, Chicago. 

The new vaccine can neutralize antibodies produced by variants such as EG.5 and BA.2.86 “which are the newest ones we’re concerned about,” Sha said. Preliminary data shows the new vaccine “looks good against EG.5 and BA.2.86,” but how much neutralizing activity the antibodies have against these variants remains unknown.

Two steps remain before you can get the booster at your doctor’s office or local pharmacy, however. The CDC’s Advisory Committee on Immunization Practices, or ACIP, is expected to vote on approving the new vaccine Tuesday. Then the new director of the CDC, Mandy Cohen, MD, MPH, will have to sign off. 

COVID cases, hospitalizations and deaths are rising across the U.S. again. According to the CDC, hospitalizations rose 15.7% in the week ending Aug. 26. Deaths rose 10.5% through Sept. 2. 

The FDA said the new vaccine should be available for anyone age 5 and older regardless of previous vaccination status as long as it’s been more than 2 months since you’ve received a COVID shot. 

Children 6 months through age 4 who have received at least one earlier COVID vaccine are eligible for one or two doses of the new vaccine. You’ll need to speak to your pediatrician to confirm dosage. 

Children in the same age group who have never received a COVID vaccine are eligible for three doses of the new Pfizer vaccine or two doses of the new Moderna formula. 

“The FDA is confident in the safety and effectiveness of these updated vaccines and the agency’s benefit-risk assessment demonstrates that the benefits of these vaccines for individuals 6 months of age and older outweigh their risks,” the agency said in a statement. 

“I think safety still weighs heavily on people’s minds,” Sha said. She emphasized that everything in this vaccine is the same as in previous ones, except for the genetic material specific to XBB1.5. “So all the safety data we have accumulated still tells us these vaccines are very safe. Honestly, billions of doses have been given and this is very well studied.”

The risk for acute myocarditis appears to be lower now as well, Sha added. “The myocarditis issue in young men, particularly young boys, really was much more an outcome when we were giving two doses very close together, and that’s not being done anymore.”
“So I think that the risk of myocarditis is also significantly lower than what we saw initially,” Sha added.

The number of people who got the previous booster fell short of expectations. In most places throughout the United States, 20% or less of the population received the updated bivalent vaccine since its approval Sept. 1, 2022, for example. Only in seven states and the District of Columbia does the percentage go above 25%, according to a CDC map

“Obviously, we’ve seen in recent weeks that cases are increasing again,” Sha said. It is difficult to predict what might happen in the winter months, “but the thing I’m telling my own patients is for those who sat out last year’s booster, ‘You know, it’s now, maybe 18 to 24 months since your last  booster. We know your levels of protection are quite low from your prior vaccines …  and maybe there’s more reason to think about getting it now.’”

A major unknown is how the cost of the new boosters, no longer free of charge, could affect their uptake. The manufacturers estimate that without health insurance they will cost $110 to $130 for each dose.

Sha has heard some reports that the federal government might provide some kind of funding for uninsured people. But, she added, “I anticipate that for anybody with Medicaid, Medicare or private insurance, it will be covered.”