Pfizer-BioNTech asks FDA for emergency use authorization for fourth COVID-19 shot

Pfizer and BioNTech have asked the Food and Drug Administration (FDA) for emergency use authorization for a fourth COVID-19 vaccine.

According to Pfizer, the company submitted the emergency use authorization for an additional booster shot that would be for adults ages 65 and older. Seniors would have had to have received the first two vaccines and the initial booster. They could have received any of the authorized Covid-19 vaccines or boosters.

Pfizer collected data from Israel during a time when the Omicron variant was widespread. Evidence showed that an additional mRNA booster can increase immunogenicity and lower rates of infections and severe illness.

Pfizer analyzed the Israeli Ministry of Health records of over 1.1 million adults aged 60 or older with no known history of a SARS-CoV-2 infection. They found that infections were 2 times lower and rates of severe illness were 4 times lower among those who received another booster when compared to those who only received a single booster shot.

Additional data from an ongoing, open-label, non-randomized clinical trial in healthcare workers ages 18 or older in Israel who had received three doses of the Pfizer Covid-19 vaccine.

Out of the 700 participants, 154 received a fourth dose of the vaccine. Evidence showed that those who received the fourth dose experienced an increase in neutralizing antibody titers.

Overall, the study did not reveal any new safety concerns for those who received an additional booster dose of the vaccine.