Federal regulators Monday granted full approval to the Pfizer-BioNTech coronavirus vaccine -- a milestone that stands a chance of helping increase inoculation rates and sparking a wave of vaccine mandates by employers and universities amid the surge of new cases and hospitalizations fueled by the delta variant.
Behavioral scientists and public health specialists who study vaccine acceptance say the FDA approval is a clarion signal that the shots are safe and effective.
"Mandating becomes much easier when you have full approval," said Dr. Carlos del Rio of Emory University. "I think a lot of businesses have been waiting for it."
The Food and Drug Administration's action marks the first licensing of a vaccine for the coronavirus, which has swept the United States in repeated and punishing waves since early 2020, exhausting nursing staffs, filling intensive care units and raising fears among both the vaccinated and the unvaccinated.
The vaccine has been approved for two doses, three weeks apart, in people 16 and older. It also remains available under emergency-use authorization for adolescents 12 to 15.
"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," FDA acting Commissioner Janet Woodcock said in a statement.
The approval was based on a clinical trial of 44,000 people, half of whom got shots, Pfizer said. The median six-month follow-up period for safety and efficacy began after participants received their second dose, the company said. The vaccine was 91% effective in preventing cases of covid-19 in that trial.
The company plans to follow the trial subjects for 24 months.
Critics for weeks had demanded that the FDA move faster on approving the vaccine, arguing that the millions of inoculations administered since late last year under an emergency-use authorization demonstrated the shots' safety and effectiveness. But even as the FDA redoubled its efforts, increasing staff and computer resources dedicated to the review, the agency insisted on six months' follow-up data for people enrolled in the pivotal clinical trial.
In the end, the vaccine approval was the fastest in the agency's history, coming less than four months after Pfizer-BioNTech filed for licensing May 7.
"It's been remarkably fast," said Holly Fernandez Lynch, a bioethics expert and lawyer at the University of Pennsylvania, who said careful handling of the approval was crucial to potentially persuading the vaccine-hesitant to get the licensed shots.
President Joe Biden took the opportunity to again urge unvaccinated Americans to get shots.
He said that for those who hesitated to get the vaccine until it received what he called the "gold standard" of FDA approval, "the moment you've been waiting for is here."
"Please get vaccinated today," the president said.
He called the approval "a key milestone in our nation's fight against covid" and stressed that inoculation saves lives. The coronavirus continues to be "a pandemic of the unvaccinated," he said, adding that those awaiting final FDA approval no longer have a reason to delay.
He also urged more leaders to require the shots as a way to "reach millions more people," adding, "If you're a business leader, a nonprofit leader, state or local leader who has been waiting for full FDA approval to require vaccinations, I call on you now to do that, require it."
Elizabeth Nichols, 18, of Akron, Ohio, said she felt "a rush of relief" after hearing the news. She already was on her way to get her first shot Monday after months of hesitation.
"I had an internal battle of whether I should get the shot or not," Nichols said in an email. "It can be scary subjecting yourself to something that is unapproved." But, she said, "The authorization proves how safe it is."
Several more cities, states and private companies announced vaccine mandates Monday. New York announced that shots are required for all public school employees, and vaccination in New Jersey is now a requirement for all state employees. Chevron announced a vaccine requirement for some of its workers. The Pentagon said it is moving forward with plans to require the shots for all troops.
They join a growing list of entities issuing such rules, but vaccination remains a political issue as well.
Although former President Donald Trump and other high-profile conservatives have acknowledged that they chose to be vaccinated to protect themselves, many Republicans in particular say they will refuse to get vaccinated.
Vaccination rates are lowest in parts of the country that are most supportive of the former president. Alabama has the lowest vaccination rate in the country.
A growing number of GOP officials have become more vocal in their push for vaccines as infection rates rise, and some have even begun to place the onus on those refusing to be vaccinated.
"It's time to start blaming the unvaccinated folks, not the regular folks," Gov. Kay Ivey, R-Ala., said last month. "It's the unvaccinated folks that are letting us down."
WHAT HAPPENS NEXT?
Some experts predicted there would not be a huge bump in vaccinations after the approval, saying they were skeptical that vaccine-avoidant people would change their minds.Gallery: Biden delivers remarks on full FDA approval of Pfizer vaccine
Full approval means the vaccine meets the same "very high standards required of all the approved vaccines we rely on every day," said Dr. Jesse Goodman of Georgetown University, a former FDA vaccine chief. That should help "anyone who still has concerns gain confidence" in the shots.
However, he suggested, "It will provide an additional nudge but not make a huge difference."
A recent surge in vaccinations, Goodman said, appears to be driven by rising concerns about the delta variant.
Others predict the full licensure will lead to more vaccine requirements by colleges, workplaces, concert venues and movie theaters.
"Based on the longer-term follow-up data that we submitted, today's approval for those aged 16 and over affirms the efficacy and safety profile of our vaccine at a time when it is urgently needed," Pfizer Chief Executive Albert Bourla said in a statement. "I am hopeful this approval will help increase confidence in our vaccine."
Bourla called the FDA's action "an important milestone that I think will unlock some of the more skeptical minds."
To get a product licensed, a company must provide vastly more data and details on the manufacturing process and relevant facilities and is subject to in-depth inspections by the FDA. Pfizer's manufacturing process will not change as a result of this approval. The vaccine remains free to U.S. residents.
The FDA licenses not only the product but also "the process by which the vaccine is made and the manufacturing site," said Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia. "There are protocols for every step of manufacturing, and that is not trivial."
"It's a great thing that it's finally getting its approval. It will be an important confidence-builder," said London School of Hygiene & Tropical Medicine anthropologist Heidi Larson, who directs the Vaccine Confidence Project.
More than 200 million doses of the Pfizer vaccine have been injected into Americans. "People who say they don't want to be first in line don't have that to worry about," Larson said.
Because the vaccines were at first authorized for emergency use, this meant that, on the fact sheet that vaccine administrators are supposed to hand out to patients, the FDA had described the Pfizer vaccine as experimental. That will now be removed.
"A full approval takes away that, 'Oh, it's experimental' kind of language. For some people, it might make a difference. They will feel more confident and comfortable," said University of Maryland School of Public Health professor Sandra Quinn, who has studied public acceptance of vaccines since the H1N1 influenza outbreak in 2009.
But Larson cautioned against expecting all of those people who adopted a wait-and-see stance to roll up their sleeves. "Not everyone goes with what they say," she noted.
Data collected by Scott Ratzan, an expert in health communication at the City University of New York Graduate School of Public Health & Health Policy, and his colleagues indicate 3% to 5% of unvaccinated Americans said they would get immunized based on this change in status. If that group does, the total U.S. vaccinated population would increase by a few million.
Experts said the biggest impact could come from employers rather than individual decisions. This summer, many employers, including federal agencies and companies such as Google and United Airlines, began telling workers they would need to be vaccinated or face termination.
Many more companies will probably adopt comparable mandates now.
"At the corporate level, that's where I think it's going to matter," said Ratzan, a co-founder of CONVINCE, an initiative to improve vaccine literacy. "People are supportive of their employer recommending it and requiring it ... . They are willing to follow if their employer recommends it."
Quinn agreed. "My expectation is that the biggest change will likely be less from individuals and more from organizations, be they industry, municipalities, etc.," she said.
Employer vaccine requirements protect workers and reinforce vaccination as a social norm, experts said.
"The more people that do it and report that 'I had no side effects' or 'I had a sore arm for a day,' it begins to also reduce fears of others," Quinn said.
LEEWAY FOR DOCTORS
Full approval gives doctors flexibility in using vaccinations, as long as the uses are considered reasonable. Such off-label use is not permitted for products under emergency authorization.
Given that increased flexibility, doctors may face pressure from patients who want booster shots soon, before the FDA clears them.
The Biden administration recently said the effectiveness of the Pfizer-BioNTech and Moderna vaccines at preventing mild and moderate covid-19 appears to be waning. Officials said they plan to roll out booster shots beginning the week of Sept. 20, assuming the FDA clears the applications from the vaccine makers.
"Many of us are worried that full approval means you don't get more of the people who should get vaccinated but instead the worried well are going to get additional doses," said a federal official who spoke on condition of anonymity.
Experts said it would be especially concerning if parents with children younger than 12 attempt to get their children vaccinated. Those inoculations have not yet been cleared, and scientists are still determining the correct doses.
Legal ambiguities might discourage doctors from using the products in a way that is not recommended, said Penn State's Lynch. For one thing, she said, it isn't clear whether doctors using the Pfizer vaccine off-label would be shielded from legal liability if someone is injured by the shot.
The Centers for Disease Control and Prevention's vaccine advisory committee is expected to meet soon to recommend use of the vaccine. Since the Advisory Committee on Immunization Practices and the CDC have recommended Pfizer for use in people 16 and older under the emergency authorization, they are virtually certain to recommend it for the licensed product.
The Pfizer-BioNTech approval is part of what is shaping up as a period of extraordinary activity on the vaccine front. Moderna, the second-most widely used vaccine in the United States, filed for full approval June 1. Johnson & Johnson, maker of the third vaccine authorized for emergency use in the United States, has said it plans to apply for approval later this year.
Pentagon spokesman John Kirby said Defense Secretary Lloyd Austin is making good on his vow to require shots once the FDA approved the vaccine. He said guidance is being developed and a timeline will be provided in the coming days.
Hospitalizations and deaths are increasing among the military. Over the past month, the number of service member deaths jumped from 25 to 34 -- more than a one-third increase.
In a memo Aug. 9, Austin said he'd seek the president's approval to make the vaccine mandatory no later than mid-September, or immediately upon FDA licensure, "whichever comes first."
The Pentagon has said the military has enough shots to meet the requirements. They will be mandated for more than 1.3 million active-duty troops and close to 800,000 in the Guard and Reserve.
Kirby said the steps Monday to make the vaccine mandatory are an effort to ensure the safety of service members. Concerns are especially acute in the military, where service members live and work closely together in barracks and on ships, increasing the risk of rapid spreading. Any large virus outbreak in the military could harm America's ability to defend itself in a security crisis.
In a message to the force this month, Gen. Mark Milley said medical professionals recommend the vaccine, and that getting the shot is key to maintaining a military that is prepared to defend the nation.
Members of the U.S. military are already required to get as many as 17 vaccines, depending on where they are deployed -- including shots for smallpox, hepatitis, polio and the flu.
As of Wednesday, more than 1 million active-duty, Guard and Reserve service members were fully vaccinated and nearly 245,000 more had received at least one shot, according to the Defense Department.
Information for this article was contributed by Ben Guarino, Laurie McGinley, Adela Suliman, Bryan Pietsch, Brittany Shammas, Tyler Pager and Eugene Scott of The Washington Post; and by Lauran Neergaard, Matthew Perrone, Jonathan Lemire and Lolita C. Baldor of The Associated Press.