FDA Commissioner Issues Vaccine Warning 0:43
(CNN) -
The U.S. Food and Drug Administration (FDA) is considering new rules for the authorization of a covid-19 vaccine, according to three sources familiar with the situation.
Calculations show that these rules would prompt an authorization beyond Election Day.
That would frustrate the hopes of President Trump, who has repeatedly said the vaccine could be ready by November 3.
The sources outlined two different scenarios that the FDA is evaluating before a pharmaceutical company can receive an emergency use authorization (EUA) for its vaccine.
"Either way, it will be Thanksgiving at the earliest before a company gets an EUA," said the first source.
That source said the FDA is expected to tell vaccine manufacturers to wait two months after giving all study participants their second dose of the vaccine until they can request an EUA.
Pfizer and Moderna, the two companies that began the phase 3 clinical trial for coronavirus vaccines in the US in July, have given second doses to less than half of their participants.
“They [the FDA] are seriously considering this measure.
They have not said 'must', but they are giving signs that this is important to them and they are moving in this direction, "said the source.
There is a second scenario that could occur instead.
A second source, a senior administration official, said the agency is expected to require companies to wait 60 days after giving half of the trial participants their second dose before they can obtain an EUA.
The measure is designed to monitor the safety of the vaccine, even if the trial has already determined its efficacy.
Under that rule, the two companies would still not get a USA by Election Day, as they have not yet given second doses to half of their volunteers.
A third source said the FDA was considering making the 50% requirement.
But that was still in the discussion stage.
Pfizer plans to enroll 44,000 volunteers in its clinical trial.
As of Monday, it had given second doses to 19,210 participants.
Moderna plans to enroll 33,000 volunteers in its clinical trial.
As of Friday, he had given second doses to 11,879 participants.
Both companies expect an initial reading of the effectiveness data, called an interim analysis, to take place in the coming weeks.
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A third AstraZeneca clinical trial is currently on hiatus in the United States, after a participant in the United Kingdom developed a neurological condition.
The news that the agency is expected to issue the new covid-19 vaccine developer guide was first reported by
The Washington Post
on Tuesday.
FDA spokeswoman Stephanie Caccomo said in an email to CNN on Tuesday: "The FDA has previously indicated that the agency intends to issue additional guidance shortly."
With "recommendations on the data and information needed to support the issuance of an EUA."
Dr. Peter Marks, who heads the FDA's Center for Biological Research and Evaluation, which evaluates vaccines for approval, has previously said that the standard for authorizing any eventual coronavirus vaccine will be as an "emergency use authorization. -plus ».
Marks said Sept. 10 that the FDA's requirements will be stricter than those of an EUA for an experimental drug, but not as stringent as the requirements for a full license.
“Taking these tests into account, we expect that we have approximately a median.
That is, about 50% of people will have more, 50% of people will have less than about two months of follow-up.
That is what we are waiting for.
It turns out that most of the adverse events that will occur after vaccination will occur within about a month and a half after vaccination, ”said Marks.
“At the time of an emergency use authorization, there will be efficacy data that has reached an intermediate analysis end point.
And we have security data that would be sufficient for a large number of people.
We are talking about 15 to 20,000 people who will make us feel reasonably confident that we understand the safety profile of the vaccine. "
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President Trump has made repeated claims that the United States will soon have a vaccine.
"It is very possible that we will have the vaccine before a very important date, specifically November 3," the president said September 16 at a press conference at the White House.
CNN's Maggie Fox contributed to this report.
Vaccine