Their application to the FDA included data showing that confirmed infections and severe illness were lower among individuals who received a second booster of the Pfizer-BioNTech vaccine.
Pfizer and BioNTech applied for an emergency use authorization (EUA) from the FDA for a second booster dose of their COVID-19 vaccine for adults 65 years of age and older who have received an initial booster of any of the authorized or approved COVID-19 vaccines.
If the FDA issues the EUA, this booster dose would be the fourth dose of the Pfizer vaccine for many older Americans. The initial series is comprised of two doses and a single booster has already been added.
The submission is based on two real-world data sets from Israel analyzed at a time when the omicron variant was widely circulating. Both data sets show evidence that an additional mRNA booster increases immunogenicity and lowers rates of confirmed infections and severe illness, according to a news release from Pfizer.
Each data set or study revealed no new safety concerns in individuals who received an additional booster dose of the vaccine, also.
One of the data sets were collected from an analysis of Israeli Ministry of Health records where over 1.1 million adults 60 years of age and older had no known history of SARS-CoV-2 infection and were eligible for an additional booster.
This data confirmed infections were two times lower and rates of severe illness were four times lower among those who received an additional booster dose of the Pfizer-BioNTech vaccine administered at least four months after an initial booster (third) dose compared to those who received only one booster dose.
Additional data included in the submission were results from an ongoing, open-label, non-randomized clinical trial in healthcare workers 18 years of age and older at a single study center in Israel who had been vaccinated with three doses of the Pfizer-BioNTech vaccine.
Among the 154 out of 700 participants who received a second booster of the Pfizer-BioNTech vaccine at least four months following the initial booster, neutralizing antibody titers increased approximately 7-fold to 8-fold at two and three weeks after the second booster compared to five months after the initial booster.
Additionally, there was an 8-fold and 10-fold increase in neutralizing antibody titers against the omicron variant at one and two weeks after the additional booster compared to five months after the initial booster, the release said.
Emerging evidence, included data from Kaiser Permanente Southern California, suggested that effectiveness against both symptomatic COVID-19 and severe diseasecaused by omicron wanes three to six months after receipt of an initial booster (third) dose. Therefore, additional booster doses may be needed to ensure individuals remain adequately protected, the release said.
According to a report by CNN, the FDA said it will review Pfizer and BioNTech's request "as expeditiously as possible using our thorough and science-based approach."
The agency also said it will convene its independent vaccine advisers, the Vaccines and Related Biological Products Advisory Committee, in April to discuss all 2022 booster shot considerations and more. A date for the meeting has not been set.