Updated COVID-19 Boosters Approved by CDC
Today, the CDC's Advisory Committee on Immunization Practices (ACIP) approved, with a vote of 13 to 1, recommending newer mRNA boosters for Americans this fall. Dr. Rochelle Walensky, head of the CDC, explained that these updated boosters could be available as early as Friday and shipments could begin after the FDA's approval on Wednesday.
Walensky stated, "The updated COVID-19 booster shots are designed to better protect against recently circulating COVID-19 variants, including BA.4 and BA.5, which share the same spike protein." She also added, "They can help restore protection that has waned since the last vaccination and provide a broader protection."
The updated booster from Pfizer/BioNTech is a 30-microgram dose, which is authorized for individuals ages 12 and above. Moderna's updated booster, containing 50 micrograms, is approved for individuals aged 18 and above. Dr. Walensky also mentioned that in the coming weeks, new boosters may be recommended for other pediatric groups.
To receive an updated booster shot, you must have completed all primary doses in the vaccine series. The CDC recommends waiting at least two months after the last dose of any COVID-19 vaccine and up to three months after an infection before receiving a new booster shot.
These new boosters were approved based on studies conducted on mice with the human ACE-2 receptor, the receptor through which the coronavirus enters our cells. While data from clinical studies showing how well they work in humans is still pending, it's expected to be available with time. To put it in context, this is similar to how seasonal flu vaccines are developed and approved each year.
While the Food and Drug Administration (FDA) reviewed the data for the two-strain boosters against the original Omicron variant BA.1 and the original virus, Moderna's two-strain boosters have not been authorized for sale in the United States. Several committee members expressed their discomfort with recommending a booster that isn't backed by human data.
Melinda Wharton, director of the CDC's National Center for Immunization and Respiratory Diseases, commented, "We use influenza vaccines every year that are based on new strains without human data." Doran Fink, deputy director of the FDA's Center for Biologics Evaluation and Research, also noted, "The FDA is satisfied with the methodology for assessing safety and effectiveness or known and potential advantages for the vaccine."
In recent studies on BA.1 and the original vaccine, the booster shots have been shown to increase immunity against various variants, providing better protection than the original single-dose vaccine. These boosters are expected to produce higher levels of antibodies.
References:
