Their application to the FDA included data showing that confirmed infections and serious illness were lower among individuals receiving another booster of the Pfizer-BioNTech vaccine.
Pfizer and BioNTech applied for an emergency use permit (EUA) from the FDA for a second booster dose of their COVID-19 vaccine for adults 65 years and older who have received an initial booster of one of the authorized or approved COVID-19 vaccines .
If the FDA issues the EUA, this booster dose will be the fourth dose of the Pfizer vaccine for many older Americans. The introductory series consists of two doses and a single booster has already been added.
The submission is based on two real data sets from Israel analyzed at a time when the omicron variant was very widespread. Both datasets show evidence that an additional mRNA booster increases immunogenicity and lowers the number of confirmed infections and serious illness, according to a press release from Pfizer.
Each data set or study also revealed no new safety concerns in individuals receiving an extra booster dose of the vaccine.
One of the datasets was collected from an analysis of the Israeli Ministry of Health records where over 1.1 million adults 60 years and older had no known history of SARS-CoV-2 infection and were eligible for an additional booster.
These data confirmed that infections were twice as low and the incidence of serious illness was four times lower among those who received an additional booster dose of the Pfizer-BioNTech vaccine given 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 professionals aged 18 years 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 another booster of the Pfizer-BioNTech vaccine at least four months after the initial booster, neutralizing antibody titers increased approx. 7 times to 8 times two and three weeks after the second booster compared to five months after the first booster.
In addition, there was an 8-fold and 10-fold increase in neutralizing antibody titers against the omicron variant one and two weeks after the additional booster compared to five months after the initial booster, the release said.
New evidence, including data from Kaiser Permanente Southern California, suggested that efficacy against both symptomatic COVID-19 and severe disease caused by omicron decreases three to six months after receiving an initial booster (third) dose. Therefore, additional booster doses may be needed to ensure that individuals remain adequately protected, the release states.
According to a CNN report, the FDA said it would review Pfizer and BioNTech’s request “as soon as possible using our thorough and science-based approach.”
The agency also said it will convene its independent vaccine advisors, 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.