The Food and Drug Administration (
FDA) on Friday authorized boosters of the Moderna and Pfizer COVID-19 vaccines for all Americans 18 or older.
“The FDA has determined that the currently available data support expanding the eligibility of a single booster dose of the Moderna and Pfizer-BioNTech COVID-19 vaccines to individuals 18 years of age and older,” Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in a statement.
An FDA analysis of immune response data supported the decision. For Moderna’s vaccine, the FDA analyzed how 149 participants from the original clinical studies reacted after being given a third dose. For Pfizer’s shot, the FDA analyzed the immune response of approximately 200 participants who got a booster.
Those who got a booster had higher antibody levels than those who did not.
Studies and real-world data show the vaccines protect well against infection and hospitalization in the months after the primary series. But after a certain point, the antibody levels begin dropping and the effectiveness plummets against infection and decreases to a lesser extent against severe disease.
The drop is more pronounced in the elderly and those who have serious underlying health conditions like obesity.
Health officials previously tried to expand access to boosters to everybody but were effectively blocked by the FDA’s vaccine advisory panel, which voted against the move. The FDA could have overruled the recommendation but did not. Instead, the agency took up a separate recommendation to make a booster available to everybody over 65 and certain groups 64 and under.
The FDA has now
side-stepped its vaccine advisory panel in making boosters available to anybody 18 or older.
