An FDA advisory panel issued the approval for people age 16 and up based on clinical trial and follow-up data on the vaccine's effectiveness from roughly 20,000 vaccine and 20,000 placebo recipients age 16 and older.
The FDA also analyzed safety data from roughly 22,000 people who received the vaccine and 22,000 people who received a placebo. The trial data found that the vaccine was 91% effective at preventing COVID-19 disease, according to the FDA.
Acting FDA Commissioner Dr. Janet Woodcock called the approval a "milestone" in the ongoing pandemic.
"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," she said in a statement.
The Pfizer vaccine will now be marketed as Comirnaty, according to the FDA, and will continue to be available to people ages 12 to 15 under the FDA's emergency use authorization.
The FDA is expected to issue a subsequent approval for the vaccine developed by Moderna in the coming weeks, while Johnson & Johnson is expected to apply soon for approval of the one-dose vaccine developed by its pharmaceutical subsidiary Janssen.
In California, state officials celebrated the Pfizer vaccine's approval and urged people to get vaccinated if they have yet to do so to drastically reduce the likelihood of developing serious illness or dying from COVID-19.
"We know the vaccines work. We know vaccines are safe. We know they save lives," California Department of Public Health Director and state Public Health Officer Dr. Tomas Aragon said in a statement. "If you are not vaccinated, let this be the milestone that gets you there."
The FDA issued its original emergency use authorization for the Pfizer vaccine Dec. 11, 2020, for people age 16 and up. In May, it expanded that authorization to children ages 12 to 15.
While some 362 million vaccine doses have been administered in the U.S. and more than 200 million Americans have gotten at least one vaccine dose, state and local officials expressed optimism that the FDA's full approval will spur more people to get vaccinated in the coming weeks.
"We hope this FDA approval removes another barrier for vaccine-hesitant members of our community to protect themselves and their loved ones," Santa Cruz County Health Officer Dr. Gail Newel said. "The Delta variant is significantly impacting our unvaccinated population, and these vaccines, along with wearing face coverings in public, are the best tools we have to protect ourselves."
In California, just over 46 million vaccine doses have been administered to roughly 25 million residents. Last week, FDA advisers and state officials also issued their respective approvals of booster vaccine doses for immunocompromised people who received the two-dose Pfizer and Moderna vaccines.
"I encourage all Californians to trust the science and protect themselves and their community by getting vaccinated," Gov. Gavin Newsom said in a statement. "With more than 80% of Californians 18 and up having received at least one dose, our work continues to close the gap in our most impacted communities and bring an end to this pandemic."
Plans for boosters
Federal health officials announced last week plans to offer COVID-19 booster shots to fully vaccinated people in an effort to fortify their immune response in the face of more contagious COVID-19 variants.
A group of public health and medical experts from within the U.S. Health and Human Services Agency issued a joint statement expressing their support for the administration of booster shots roughly eight months after full vaccination with the two-dose vaccines developed by Pfizer and Moderna.
While the two vaccines remain highly effective at preventing serious infections and death, the officials argued that preemptively boosting the immune response, particularly among people with weakened immune systems and other high-risk demographics like nursing home residents, would maximize protection against the delta variant and subsequent variants, which could be even more potent.
"Our top priority remains staying ahead of the virus and protecting the American people from COVID-19 with safe, effective, and long-lasting vaccines especially in the context of a constantly changing virus and epidemiologic landscape," the group said in its joint statement.
Booster doses will also likely be necessary for those who have gotten or will get the one-dose Johnson & Johnson vaccine, but federal officials expect to have more data in the coming weeks since the J&J vaccine did not become available in the U.S. until March.
The formal approval of booster shots remains subject to safety and effectiveness evaluations by the FDA and a CDC advisory panel.
The CDC's vaccination advisory panel already issued an approval of booster doses the week before for people with weakened immune systems who are more likely to suffer so-called breakthrough COVID-19 infections because their immune response is not as robust as that of people with fully functional immune systems.
State public health officials have also given the go-ahead to booster doses for immunocompromised people after the Western States Scientific Safety Review Workgroup -- which includes officials from Nevada, Oregon, Washington and California -- issued its approval last week.
Vaccine proof rules
State public health officials tightened vaccine verification requirements last week for large indoor events, requiring vaccine proof or a negative COVID-19 test for events with more than 1,000 people.
Starting Sept. 20, the California Department of Public Health will require indoor venues to confirm the vaccination status of attendees or that they've tested negative for COVID-19 within 72 hours of an event.
Venues will also no longer be able to allow event attendees and spectators to self-attest their vaccination status and are encouraged to utilize the state's digital vaccine record system.
Aragon cited the spread of the ultra-contagious delta variant as well as the COVID-19 vaccines' success at preventing serious illness and death as the main reasons for the verification requirements.
"By requiring individuals to be vaccinated, or test negative for COVID-19 at large events, we are decreasing the risk of infection, hospitalization and death," Aragon said.
The state had previously required vaccine or negative test verification for events of 5,000 or more people through at least Oct. 1. Until Sept. 20, those rules will remain in effect.
State public health officials touted support for the new guidelines from entertainment event giants like Live Nation Entertainment and AEG as well as Californians for the Arts.
The guidelines will keep the verification system in place through at least Nov. 1, according to the CDPH.