The FDA granted full approval to Pfizer's COVID-19 vaccine Aug. 23 for use in people ages 16 and older, and said it will now be marketed as Comirnaty.
The shot is still available under emergency use authorization for people ages 12 and up.
"While this and other vaccines have met the FDA's rigorous, scientific standards for emergency use authorization, as the first FDA-approved COVID-19 vaccine, the public can be very confident that this vaccine meets the high standards for safety, effectiveness, and manufacturing quality the FDA requires of an approved product," acting FDA Commissioner Janet Woodcock, MD, said in a news release.
The FDA's decision is based on effectiveness data from about 20,000 vaccine and 20,000 placebo recipients ages 16 and older. The safety of the shot was evaluated in about 22,000 vaccine recipients and 22,000 placebo recipients.
The agency found that the shot was 91 percent effective at preventing COVID-19 and potentially serious outcomes, including hospitalization and death.
About 12,000 vaccine recipients have been monitored for at least 6 months following their second dose. The most commonly reported side effects observed were pain, redness and swelling at the injection site, fatigue, headache, muscle or joint pain, chills and fever.
"Our scientific and medical experts conducted an incredibly thorough and thoughtful evaluation of this vaccine. We evaluated scientific data and information included in hundreds of thousands of pages, conducted our own analyses of Comirnaty’s safety and effectiveness, and performed a detailed assessment of the manufacturing processes, including inspections of the manufacturing facilities," Peter Marks, MD, PhD, director of FDA's Center for Biologics Evaluation and Research, said in the news release.
The FDA also said it conducted a rigorous evaluation of the risk of myocarditis and pericarditis — two rare conditions that involve inflammation of the heart — following vaccination with Pfizer's shot. Both conditions see less than 200,000 cases per year in the U.S. and have been seen in a small fraction of COVID-19 shot recipients.
The agency found the shot does cause an increased risk of both, particularly within seven days following the second dose, but didn't specify how much the risk is increased.
The risk is higher in males under age 40 compared to females and older males, and is highest in males ages 12 through 17. Most people's symptoms are resolved, though some have required intensive support, the agency said. The shot's prescribing information includes a warning about the risks.
The FDA is requiring Pfizer to conduct postmarket studies to further assess the risks of myocarditis and pericarditis following vaccination. Though not required by the FDA, Pfizer has also said it will conduct postmarket studies on the shot's outcomes in pregnant people.
Pfizer's COVID-19 vaccine, developed in partnership with BioNTech, has been available under emergency use authorization for people ages 16 and up since Dec. 11 and for people ages 12 and up since May 10.
"We have not lost sight that the COVID-19 public health crisis continues in the U.S. and that the public is counting on safe and effective vaccines. The public and medical community can be confident that although we approved this vaccine expeditiously, it was fully in keeping with our existing high standards for vaccines in the U.S.," Dr. Marks said.
The American Medical Association, American Hospital Association and American Nurses Association released a joint statement applauding the FDA's decision to fully approve the vaccine, calling it a "major step forward in the worldwide effort to end this pandemic."
"According to recent polling, 30 percent of unvaccinated people said they were waiting for vaccines to receive full approval before getting vaccinated. We are there now; this vaccine is fully approved. If uncertainty was holding you back, now is the time to act. And if you still have questions about the vaccines or about COVID-19, please consult your healthcare professional," the organizations urged. "Science, data, and thorough research have given us the tools to defeat COVID-19. With the delta variant surging, there has never been a better time to get vaccinated."
They also encouraged more healthcare organizations to mandate vaccinations.
Read the FDA's full news release here.