Pfizer on Monday announced it submitted data to the federal Food & Drug Administration regarding the results of Phase 1 trials for a potential COVID-19 vaccine booster shot.
In a press release, Pfizer said it would also submit the data to the European Medicines Agency in the coming weeks.
Late last month, Pfizer said that initial studies showed that a third dose of its COVID-19 vaccine, taken about eight or nine months after the first two doses, produced high levels of antibodies that fight off the virus.
In its findings, Pfizer said data suggests that after a third dose of its vaccine, the level of antibodies effective against the delta variant could be more than five times higher than after a second dose of the vaccine in people ages 18 to 55, and more than 11 times higher in people ages 65 to 85.
"We continuously strive to stay at least one step ahead of the virus. This is why we aim to expand access to our vaccine for people around the world and are working on various approaches as part of our comprehensive strategy to address the virus and its variants today as well as in the future," said Dr. Ugur Sahin, the CEO and Co-founder of BioNTech, who developed the vaccine in partnership with Pfizer. "This initial data indicate that we may preserve and even exceed the high levels of protection against the wild-type virus and relevant variants using a third dose of our vaccine. A booster vaccine could help reduce infection and disease rates in people who have previously been vaccinated and better control the spread of virus variants during the coming season."
Testing for a booster shot of the vaccine is currently in Phase 2 trials, and Pfizer said Monday that Phase 3 trials would begin "shortly."
Pfizer's announcement comes just days after the CDC and the FDA approved the use of a booster shot for people with compromised immune systems.
It's currently unclear how long COVID-19 vaccines offer protection against the virus. However, last week, Dr. Anthony Fauci told multiple media outlets that boosters would likely be needed in the future.
"No vaccine, at least not within this category, is going to have an indefinite amount of protection. So, an answer to your question, it's right. Inevitably, there will be a time when we'll have to get boosts," Fauci said.
Fauci later clarified that the U.S. currently has enough vaccines in stock to administer booster shots should they be formally recommended and that the government is constantly monitoring supply levels.