Less than a year after the unprecedented effort began, the first COVID-19 vaccines are expected to reach Americans within weeks. No one knows for certain, but Dec. 13 is the first possible day the vaccine could be administered – although the week after is more likely. Here's how we get there:
Pfizer and its German collaborator BioNTech applied for emergency use authorization for their COVID-19 vaccine from the Food and Drug Administration.
Moderna is expected to send in its application for its vaccine one to two weeks later, perhaps by Dec. 4.
An emergency use authorization is a fast track vaccine authorization that can be processed much more quickly than the usual Biologics License Application, which results in FDA licensing a drug or vaccine.
The FDA is expected to take one to three weeks to go through the application and make a decision on issuing the emergency authorization.
"It's typically months, occasionally weeks," said Dr. Greg Poland, director of the Mayo Clinic's Vaccine Research Group.
Before the FDA issues a license or an emergency use authorization, its policy is to have an external, independent committee known as the Vaccines and Related Biological Products Advisory Committee review the application. VRBPAC holds public meetings during which it discusses and then votes on whether to recommend the FDA approve or authorize the vaccine.
Its recommendation is nonbinding but is usually followed by the FDA.
A VRBPAC meeting to evaluate Pfizer's candidate vaccine has been scheduled for Dec. 10.
Dr. Moncef Slaoui, chief adviser to Operation Warp Speed, speaks in the Rose Garden of the White House, Friday, Nov. 13, 2020, in Washington.
EVAN VUCCI, AP
If VRBPAC votes on Dec. 10, its decision would immediately go to the FDA. At that point, FDA staff would make a final determination.
While this will likely take a few days, theoretically, Friday, Dec. 11, would be the earliest date FDA could authorize the vaccine but the week of Dec. 14 is considered more likely.
General Gustave Perna, Chief Operating Officer of Operation Warp Speed, has said on multiple occasions that vaccine distribution will begin within 24 hours after an authorization is issued by FDA. Vaccine will be shipped to all 50 states that day, allocated by population.
Once a vaccine is authorized, Operation Warp speed could begin shipping vaccine to distribution centers. However it can't be given to health care providers until one more committee makes a decision.
Pfizer's COVID-19 vaccine is being shipped in specially designed, insulated containers that hold between 195 and 975 five-dose vials and are about the size of a carry-on suitcase. The vaccine must be stored at subzero temperatures.
The final vote will come from the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices. The ACIP makes the official decision on who should get the vaccine and in what order.
In October, the National Academies of Sciences, Engineering, and Medicine outlined a plan for fair distribution that's being used as a framework by the CDC committee, but ACIP has the final say.
ACIP isn't allowed to make a recommendation before a vaccine has been authorized or approved. Typically, this would happen within weeks of FDA's action. But in this case, several members have suggested such a meeting could take place the day after the vaccine is authorized.
The earliest such a meeting could happen would be Dec. 12. Once it votes, the ACIP submits a decision memo to the CDC director for approval. Once approved, immunizations can begin.
That means Sunday, Dec. 13, likely would be the first possible date COVID-19 vaccine could be administered across the USA, though the week of Dec. 14 is more likely. The initial doses will go to front-line health care workers such as doctors, nurses and EMTs.
By the end of December, Perna said Operation Warp Speed expects to have about 40 million doses of the two vaccines available for distribution. The Pfizer and Moderna vaccines both require two doses given between 21 and 28 days apart. So, 40 million doses would be enough to vaccinate about 20 million people.
"This may be the most ambitious vaccination program the United States has ever implemented," said John Grabenstein, general manager of Vaccine Dynamics and editor for the Immunization Action Coalition, a vaccine information nonprofit.
"The influenza vaccination program of 1976 reached about 70 million people. Poliovirus vaccine was rapidly distributed in 1955. The United States has more people now than in those eras, but the scale of this coronavirus vaccine program is impressive," he said.
More vaccine will be rolled out in 2021 and distributed in stages, prioritizing people at risk of infection or severe disease. The general healthy U.S. population is expected to have access beginning in April, according to Dr. Anthony Fauci, the nation’s leading infectious disease expert.