December 11, 2020 11:00 PM, EST

Pfizer Vaccine Cleared in US

The Pfizer Global Supply Kalamazoo manufacturing plant. (Paul Sancya/Associated Press)The Pfizer Global Supply Kalamazoo manufacturing plant in Portage, Mich. (Paul Sancya/Associated Press)

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Pfizer Inc. gained emergency U.S. authorization for its COVID-19 vaccine on Dec. 11, completing an unprecedented scientific sprint that could eventually help bring an end to a pandemic that has killed nearly 300,000 Americans.

The Food and Drug Administration’s decision to authorize use of Pfizer and partner BioNTech SE’s vaccine will now set in motion a complicated immunization drive that will launch across the country in coming days. Among the first to be inoculated will be health care workers and seniors living in long-term care facilities.

“With science guiding our decision-making, the available safety and effectiveness data support the authorization of the Pfizer-BioNTech COVID-19 vaccine because the vaccine’s known and potential benefits clearly outweigh its known and potential risks,” Peter Marks, the head of the FDA’s office that oversees vaccines, said in a statement.

The approval also caps a fraught political struggle that has seen President Donald Trump push drug regulators to swiftly clear a vaccine. In the final hours of the review Dec. 11, White House Chief of Staff Mark Meadows suggested to FDA Commissioner Stephen Hahn that failure to clear the vaccine for use soon could cost him his job.

Pfizer’s shot is a landmark scientific achievement, a vaccine built from a breakthrough technology in a matter of months, in the face of a pandemic that has sickened millions worldwide. It has already been cleared by regulators in the U.K., Canada and other countries.

“This is one of the greatest scientific accomplishments in history,” Trump said in a video on Twitter. “It will save millions of lives and soon end the pandemic once and for all.”

A shot similar to Pfizer’s made by Moderna Inc. is expected to gain U.S. clearance next week, providing the country with a potent combination for beating back the pathogen. More vaccines are also expected to be brought to market next year, expanding the arsenal doctors will have to rein in COVID-19.

Pfizer’s vaccine, like Moderna’s, uses a new technology called messenger RNA that turns the body’s own cells into vaccine-producing factories to fight the coronavirus. In a trial of almost 44,000 people, it was 95% effective at preventing symptomatic cases of COVID-19, protecting people of all ages and ethnicities. Crucially, it was able to prevent the most severe infections.

Among the vaccine front-runners, the Pfizer-BioNTech shot is the only one that didn’t take funding from the White House-led Operation Warp Speed program to accelerate development, manufacturing and distribution of COVID-19 shots. However, the two companies have secured a $2 billion deal to supply 100 million doses to the U.S., with an option for 500 million more.

The shot requires special freezers to be kept at extra cold temperatures until a few days before use, making distribution more complicated. Pfizer has developed special dry-ice containers to make it easier to store for facilities that don’t have the needed equipment.

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