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The FDA is leaning toward authorizing half-dose booster shots of Moderna’s COVID-19 vaccine.
Federal regulators believe the half-dose shot could provide enough protection. The move could broaden the U.S. booster campaign, Bloomberg News reported, though it’s unclear when an official announcement about the Moderna vaccine will come.
Moderna’s initial shots contained 100-microgram doses, and the company’s submission for extra shots has pushed for 50-microgram boosters. In comparison, Pfizer’s initial shots and boosters contain 30-microgram doses.
A half-dose shot could make side effects from a booster less likely, Bloomberg News reported. If the FDA approves it, Moderna could produce more doses to distribute globally, which could ease supply concerns and send more shots to countries that haven’t given many first shots.
As of Tuesday evening, Moderna, the FDA, and the White House declined to comment on the half-dose plan, Bloomberg News reported.
For now, booster shots are available to recipients of the Pfizer vaccine who are ages 65 and older, adults living in long-term care facilities, adults with certain health conditions, and workers who face high risks of contracting COVID-19. Those who are eligible for a third shot can receive one 6 months after their second dose.
So far, the side effects reported after a third dose appear to be similar to side effects seen after a second dose, according to new CDC data published this week.
More than 12,500 vaccine recipients completed the CDC’s “V-safe” survey after receiving a booster shot. Most said side effects were “mild or moderate,” including fever, headache, and reactions around the injection site such as itching, pain, redness, and swelling.
“This report includes some of the data of our early experience with third doses that FDA and CDC reviewed when they made their recommendations about boosters,” Rochelle Walensky, MD, the CDC director, said during a news briefing on Tuesday.
“We will continue to evaluate data as it becomes available, in real time and with urgency, and update our recommendations to make sure that all of those at risk have the protection they need,” she said. “This includes those who received the Moderna and J&J vaccines as their primary vaccine and also those younger Americans who are not currently eligible for a booster dose.”
Bloomberg News: “FDA Leans Toward Authorizing Moderna Booster at a Half Dose.”
CDC: “Safety Monitoring of an Additional Dose of COVID-19 Vaccine — United States, August 12-September 19, 2021.”
C-SPAN: “White House COVID-19 Response Team Briefing,” Sept. 28, 2021.