Pfizer’s COVID-19 vaccine got emergency authorization from federal regulators on Friday, clearing the way for the shipment, distribution and eventual administration of the shots.

The decision, first reported by The New York Times, marks a historic scientific achievement and suggests an end to the coronavirus pandemic may be in sight, although the timing of a return to normalcy will depend on whether other vaccines in development also come online soon — and how well federal, state and local authorities handle the logistical challenges of reaching a diverse, geographically dispersed population of 330 million people.

Authorization from the U.S. Food and Drug Administration followed a public meeting Thursday by an advisory committee reviewing research on the vaccine’s safety and efficacy. It also followed months of pressure from President Donald Trump ― who, according to a report in The Washington Post, told FDA head Stephen Hahn to resign if the agency didn’t approve the vaccine by Friday evening.

But most experts had expected FDA authorization anyway, purely on the merits, because the results of clinical trials were so overwhelmingly positive.

In tests that Pfizer conducted over the past few months, the vaccine reduced the likelihood of developing symptoms and testing positive for COVID-19 by 95%. The reported side effects included sore arms, headaches, fatigue and fever that lasted a few days.

In a briefing summary before the advisory board meeting, FDA reviewers described these effects as “mild to moderate” and said they didn’t lead to long-lasting harm. “The known and potential benefits of the Pfizer-BioNTech COVID-19 Vaccine outweigh its known and potential risks for use in individuals 16 years of age and older,” the reviewers concluded.

Seventeen of the advisory committee’s 22 members ultimately voted in favor of recommending the vaccine. The dissenters (four “no” votes and one abstention) said their only reservation was whether the data on 16- and 17-year-olds was sufficient to authorize vaccine use at those ages.

Like the majority of its advisory committee, the FDA decided that the evidence was strong enough. Under the ruling, people as young as 16 will be able to get the shots.

The FDA’s “emergency use authorization” process allows for expedited review of new pharmaceutical products in cases of urgent need. The urgency in this case could not be more clear, with caseloads rising, hospital intensive care units running out of space, and daily deaths now exceeding 3,000.

Officials from Pfizer and the Trump administration have said shipments from factories will begin right away so the first doses can be administered within days.

The first batches of shots will go to health care workers, as well as staff and residents of long-term care facilities, under instructions that each state has issued based on federal guidelines. Essential workers will be next and then, as supply ramps up in the coming months, vaccines will become available to the rest of the population.

A Scientific Breakthrough In Record Time

The rapid development of a usable COVID-19 vaccine less than one year after cases first appeared in the U.S. is especially remarkable given that Pfizer’s will be the first mass-produced vaccine to use “messenger RNA” or mRNA, a form of genetic material that the body uses to manufacture proteins.

An mRNA vaccine introduces a specially engineered strand that includes coding for part of a pathogen ― in this case, the protein spikes that protrude from the surface of the novel coronavirus.

The immune system learns to recognize the protein so that it can react quickly and quash the full virus upon exposure.

Research has not yet established whether the Pfizer vaccine prevents COVID-19 infection and spread or whether it merely prevents symptoms. The duration of protection isn’t yet clear, either, and won’t be without more study.

But one intriguing finding is that vaccine recipients developed a strong immune response following the first dose. Scientists have said the second dose remains important, because the response was even stronger afterward and because it’s not yet clear how long that initial response lasts.

Although mRNA technology had been the subject of research for many years, the speedy translation of that research into a functional, widely produced vaccine would not have been possible without a new, all-out effort from both the private and public sectors ― including funding and coordination from the Trump administration’s Operation Warp Speed project as well as investments from foreign governments.

In the case of Pfizer, that money came through its European partner, BioNTech, which got research money from the German government.

The Next Big Challenge Is Distribution

On a conference call this week, Health and Human Services Secretary Alex Azar said that the goal remains to reach 20 million Americans by year’s end, 50 million by the end of January and 100 million by the end of March.

And by the summer, Azar said, there should be enough vaccines for all Americans who want it.

Margaret Keenan, 90, is the first patient in Britain to receive the Pfizer/BioNtech COVID-19 vaccine at University Hospital, administered by nurse May Parsons, on Dec. 8, 2020. 

Those estimates assume the approval and distribution of other COVID-19 vaccines in development, including an mRNA vaccine from Moderna that has shown similar results in its clinical trials. The FDA is set to review Moderna’s vaccine on Dec. 17.

But even if more vaccines win approval and even if production proceeds smoothly, distributing and then administering the vaccine will present an enormous, unprecedented logistical challenge.

During the initial wave, when supply is limited to the highest priority groups, administration of the vaccine will mainly be the job of hospitals (which will take care of their workers) and the big pharmacy chains, CVS and Walgreens (which will take care of long-term care residents and staff).

An open question is what happens after that, if, as hoped, mass production dramatically increases the available supply. States are in charge of formulating and then carrying out these plans and it’s not yet clear they’ve made enough arrangements ― or have enough resources ― to handle so many shots at once or to reach rural and marginalized communities.

The task is especially difficult because of the two-dose regimen and the need to make sure people get second vaccinations.

There’s still a little bit of time for states to make those plans ― and for Congress to appropriate the money states need. But the longer it takes to get the vaccine to people, the longer it will be before the U.S. returns to something resembling normal.


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