(CN) — The makers of the vaccine most used in the United States to inoculate people against Covid-19 has sought regulatory permission that would allow any adult who originally received the two-shot regimen to get a booster dose.
Pfizer and BioNTech announced Tuesday they asked the U.S. Food and Drug Administration to amend the emergency use authorization of their Covid-19 vaccine, saying participants in a study that received a booster shot had 95% vaccine efficacy at a time when the Delta variant dominated transmission of the virus.
The move comes weeks after authorities green-lit booster shots of Pfizer and Moderna for Americans 65 years and older, those in high-risk setting and individuals with underlying medical conditions. Authorities have also said those who received the one-dose inoculation from Johnson & Johnson should receive a second shot.
In September, an FDA panel had balked at the idea of offering Pfizer boosters to all Americans, citing a lack of data about a third dose’s safety.
Pfizer said it was making the new request to expand eligibility for the booster doses after it announced the results of study with 10,000 participants in Brazil, South Africa and the United States.
“The adverse event profile was generally consistent with other clinical safety data for the vaccine, with no new safety concerns identified,” the press release says.
While the request seeks to amend the vaccine’s emergency use authorization, Pfizer’s shot received full FDA approval for the two-dose regime in August.
In the United States, 107 million individuals have been vaccinated with Pfizer, followed by 71 million vaccinated with Moderna and 15 million vaccinated with Johnson & Johnson's shot, according to data kept by the CDC. Pfizer has already delivered 16 million booster doses.
In an emailed statement, FDA press officer Alison Hunt said it is unclear how long the agency will take to evaluate Pfizer’s study, but its review will be done “as expeditiously as possible.” And after an initial review, the FDA will decide whether to call a meeting of the independent advisory committee that evaluates vaccines.
“As we have with all Covid-19 vaccines, we intend to be as transparent as possible with this process,” Hunt wrote.
Read the Top 8
Sign up for the Top 8, a roundup of the day's top stories delivered directly to your inbox Monday through Friday.