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FDA grants full approval to Pfizer's Covid vaccine

Experts praised the decision, saying approval could help ease some vaccine hesitancy and pave the way for more vaccination mandates.

The Food and Drug Administration granted full approval to Pfizer-BioNTech's two-dose vaccine Monday for people ages 16 and up, making it the first Covid-19 vaccine to pass this final regulatory hurdle.

"The FDA's approval of this vaccine is a milestone as we continue to battle the Covid-19 pandemic," acting FDA Commissioner Dr. Janet Woodcock said in a statement. "While millions of people have already safely received Covid-19 vaccines, we recognize that for some, the FDA approval of a vaccine may now instill additional confidence to get vaccinated. Today's milestone puts us one step closer to altering the course of this pandemic in the U.S."

Full coverage of the Covid-19 pandemic

Full approval may help persuade some vaccine-hesitant people to get vaccinated. A Kaiser Family Foundation survey from June found that 3 in 10 unvaccinated adults would be more likely to get the shots if a vaccine were fully approved.

The FDA's decision may also pave the way for more vaccination mandates: Many businesses were waiting for full approval before they required employees to be vaccinated.

Public health experts praised the decision.

"We are ecstatic with anything that could potentially get even one single extra person vaccinated," said Dr. Joseph Khabbaza, a pulmonary and critical care specialist at the Cleveland Clinic.

"Full approval could not come at a more important time, as the highly contagious delta variant continues to drive up caseloads and deaths across the U.S.," Dr. Richard Besser said in a statement. Besser is the Robert Wood Johnson Foundation president and CEO and a former acting director of the Centers for Disease Control and Prevention. "I am hopeful that full approval will address any remaining concerns and will move many people to a 'yes' on vaccination."

Still, Besser said the lack of vaccines in middle- and low-income countries "represents a global failure," adding that "ensuring an adequate supply of vaccines in every country and community must be a health, economic, and moral imperative for the world."

Pfizer CEO Albert Bourla, in a wide-ranging interview Monday with NBC News' Lester Holt, said the FDA's full approval should help ease hesitancy and convince more people to get the shots.

"For those people that they were a little bit reluctant because they wanted to see full approval, now they have the full confirmation of one of the most respected agencies in the world, the FDA, that the ... vaccine is effective and safe," he said.

Bourla also championed a need for booster. “The booster will be needed because of the combination of the delta variant ... and the fact that the immunity after six months starts waning. So a booster dose is a must."

Last week, federal health officials announced that, starting Sept. 20, people who received the Pfizer vaccine will be eligible for third doses eight months after their second doses. The FDA has not yet signed off on a third dose for the general population. However, people with compromised immune systems are able to get the extra shot.

Pfizer's vaccine is one of three in use in the U.S. Moderna has also applied for full approval, also known as a Biologics Licensing Application. Johnson & Johnson has not yet applied for full approval and remains in use under emergency authorization.

Pfizer's product was the first Covid vaccine to gain emergency use authorization, in December. As of Monday, more than 204 million doses of the Pfizer vaccine have been given in the U.S., according to the CDC.

While Monday's approval does not cover young people ages 12 through 15, that group can still get the Pfizer vaccine through emergency use authorization.

No Covid vaccines have been authorized or approved for use in children under 12. Those are expected later this fall or winter.

Off label use

Full approval by the FDA of any medication means that doctors are able to prescribe the product "off label" — a practice in which doctors prescribe approved drugs for unapproved uses.

Off label use is common: according to the Agency for Healthcare Research and Quality, 20 percent of prescriptions are written are off label. For example, the diabetes drug metformin is sometimes prescribed for weight loss because one of its side effects is to lower a person's appetite.

Full approval of Pfizer's vaccine means that technically, doctors can give the shots to kids 11 and younger, however, the FDA and pediatricians strongly discourage the practice, citing a lack of safety and efficacy data.

"We are not recommending that children younger than age 12 be vaccinated with this vaccine. It would not be appropriate," Woodcock said during a press briefing Monday.

Vaccine doses for young children will likely be lower than what is currently given to teens and adults.

Kids "are not just small adults," Woodcock said. "We really would have to have the data and the appropriate dose before recommending that children be vaccinated."

Dr. Natasha Burgert, a pediatrician in Overland Park, Kansas, and a national spokesperson for the American Academy of Pediatrics, said that overall, clinicians are unlikely to use the vaccines off label in children.

"We don't give vaccines off label. That'd be very irresponsible," Burgert said.

The AAP urged parents of younger children to wait until the clinical trials in kids are finished. "The clinical trials for the Covid-19 vaccine in children ages 11 years old and younger are underway, and we need to see the data from those studies before we give this vaccine to younger children," the group said in a statement.

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Antonio Planas contributed.