By Hailey Konnath

Law360 (December 11, 2020, 11:57 PM EST ) The U.S. Food and Drug Administration gave Pfizer and BioNTech the green light Friday to begin distributing their COVID-19 vaccine throughout the U.S., issuing its first emergency-use authorization and paving the way for vaccinations of some groups to begin within days.

The authorization comes at a pivotal time in the pandemic, as cases continue to skyrocket across the country, intensive care units reach capacity and health care worker shortages strain the system. As of Friday, more than 291,500 individuals in the U.S. had died of the disease, according to the Centers for Disease Control and Prevention.

And it means Pfizer and BioNTech can immediately begin distributing millions of doses of the vaccine to health care workers, who are first in line. The federal government has said it plans to ship 2.9 million doses within hours of regulatory approval. Pfizer reportedly has 6.4 million doses on hand for distribution in the U.S.

FDA Commissioner Dr. Stephen M. Hahn hailed Friday's authorization as "a significant milestone in battling this devastating pandemic." 

Hahn said in a statement that the authorization followed a review process that involved input from independent scientific and public health experts as well as an evaluation by the agency's scientists. The vaccine meets the agency's "rigorous, scientific standards for safety, effectiveness and manufacturing quality," he said.

The decision came one day after an FDA advisory committee voted to recommend approval of Pfizer's and BioNTech's emergency-use authorization request. The committee voted 17-4 with one abstention, with the majority deciding that, based on available scientific evidence, the benefits of the vaccine outweigh the risks for those who are 16 and older.

The go-ahead was also announced just hours after President Donald Trump publicly — and reportedly privately — pressured the agency to approve the vaccine. The FDA is "a big, old, slow turtle," Trump tweeted Friday morning.

"Get the dam vaccines out NOW, Dr. Hahn," he wrote.

Meanwhile, Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, assured the public in Friday's statement that science guided the agency's decision-making. 

"Efforts to speed vaccine development have not sacrificed scientific standards or the integrity of our vaccine evaluation process," he said. 

According to The Washington Post, White House Chief of Staff Mark Meadows told Hahn to be prepared to resign if the FDA didn't approve the vaccine by the end of Friday. The Post said the information came from people familiar with the situation who spoke on the condition of anonymity.

The U.S. is the sixth country to grant emergency approval to Pfizer's and BioNTech's vaccine. Most recently, Canada endorsed the vaccine on Wednesday. The U.K. backed it last week.

The FDA's authorization began to look more likely Tuesday, when the agency's scientists endorsed the vaccine in a report. The scientists found there were no safety issues that would bar emergency-use authorization and agreed with Pfizer and BioNTech that the two-dose vaccine is about 95% effective.

The companies filed an emergency approval request on Nov. 20, a submission that included data from a phase 3 clinical study that began in July. In that study, 43,661 volunteers at 150 clinical trial sites across the U.S., Europe, Latin America and South Africa were given either doses of the vaccine or a placebo, according to the statement.

Out of the pool of participants, 162 who received a placebo developed COVID-19, while only eight participants who were given the vaccine — dubbed BNT162b2 — caught the virus.

Pfizer said it plans to seek full FDA approval in April. Once the FDA grants a biologics license application, it becomes more difficult for other potential vaccines to get emergency-use authorization. That's because EUAs are only issued when no viable FDA-approved alternative exists.

But Doran Fink of the FDA's vaccine division said an exception may be granted if, for example, there's a limited supply of the first FDA-approved COVID-19 vaccine, which is likely to be the case.

Moderna has also requested emergency authorization for its vaccine, which it claims is 100% effective at preventing severe COVID-19 cases and 94% effective at preventing infection. The company lodged its application Nov. 30.

While many questions about the vaccine remain, including whether it will stop the transmission of COVID-19, Pfizer said Thursday it expects to have data next year on how well the vaccine works to prevent asymptomatic infection.

--Additional reporting by Britain Eakin, Adam Lidgett and Kevin Stawicki. Editing by Breda Lund.

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