Pfizer submitted an application to the Food and Drug Administration Friday for an emergency use authorization for its experimental Covid-19 vaccine.
Early results from Pfizer's Phase 3 clinical trials have yielded promising news: Two shots, given three weeks apart, appeared to be 95 percent effective in preventing symptomatic Covid-19.
Pfizer and its German partner BioNTech are poised have 50 million doses available this year and 1.3 billion in 2021, using facilities both in the United States and Belgium.
"Our work to deliver a safe and effective vaccine has never been more urgent, as we continue to see an alarming rise in the number of cases of COVID-19 globally," Dr. Albert Bourla, Pfizer chairman and CEO, said in a news release.
"Filing in the U.S. represents a critical milestone in our journey to deliver a COVID-19 vaccine to the world and we now have a more complete picture of both the efficacy and safety profile of our vaccine, giving us confidence in its potential."
The companies said they have also "initiated rolling submissions" with medical regulators in Europe and the United Kingdom, and that they intend to "submit applications to other regulatory agencies worldwide in the coming days."
One potential stumbling block for the Pfizer vaccine is its requirement of ultracold storage. The shots must be stored at minus 94 degrees Fahrenheit — far colder than standard cooling systems at health care facilities across much of the country.
To help accommodate the extra refrigeration requirement, Pfizer has developed a supercool storage unit packed with dry ice.
On Thursday, Health and Human Services Secretary Alex Azar said the imminent application from Pfizer will be reviewed by an independent board of scientists before an authorization is granted.
"Hope and help are on the way," he said.
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Still, it is clear that more than one Covid-19 vaccine will be necessary to fight the pandemic. The drugmaker Moderna is also expected to file for emergency use authorization of its vaccine candidate in the coming weeks.
Overall, more than 100 Covid-19 vaccines are either in development or in clinical trials.