Moderna is seeking emergency use authorization of a second booster shot of its COVID-19 vaccine for all adults. The drugmaker submitted its request to the FDA March 17.
"The request to include adults over 18 years of age was made to provide flexibility to the U.S. Centers for Disease Control and Prevention and healthcare providers to determine the appropriate use of an additional booster dose of mRNA-1273, including for those at higher risk of COVID-19 due to age or comorbidities," Moderna said in a statement, adding the submission is based in part on recent vaccine efficacy data from the U.S. and Israel after the emergence of omicron.
The request comes days after Pfizer and its partner, BioNTech, asked the FDA to authorize a second booster shot of their vaccine for people 65 and older. Their request was based on two real-world data sets from Israel, which showed evidence the additional dose boosts immunogenicity and lowers rates of confirmed infections and severe illness. Pfizer also said emerging evidence suggests effectiveness of its initial booster against symptomatic and severe infection wanes within three to six months and the additional dose restores antibody levels to those after the first booster.
A rise in cases driven by the BA.2 subvariant across Europe have spurred health experts' concern over what could play out in the U.S. in the coming weeks.
"Our experience with delta and omicron is that what happens with Europe doesn't stay in Europe; it hits us," Jay Varma, MD, epidemiologist and director of Weill Cornell Medicine's Center for Pandemic Prevention and Response in New York City, told The Wall Street Journal.
During a March 17 meeting among House Democrats, Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, said current data suggests protection against hospitalization begins to wane four or five months after an initial booster.
"I would project that sooner or later, we will need a fourth [dose]," Dr. Fauci said, adding that at first, it may only be needed for older Americans and those with underlying medical conditions, Bloomberg reports.