(CNN)In an interview with the Financial Times, US Food and Drug Administration Commissioner Dr. Stephen Hahn said the agency could consider emergency use authorization or approval for a Covid-19 vaccine before Phase 3 trials are complete.
"It is up to the sponsor [vaccine developer] to apply for authorisation or approval, and we make an adjudication of their application," Hahn told the Financial Times. "If they do that before the end of Phase Three, we may find that appropriate. We may find that inappropriate, we will make a determination."
Hahn noted that an EUA is not the same as FDA approval.
"Our emergency use authorisation is not the same as a full approval," he said. "The legal, medical and scientific standard for that is that the benefit outweighs the risk in a public health emergency."
Hahn said the vaccine decision would be based on data, not politics.
"We have a convergence of the Covid-19 pandemic with the political season, and we're just going to have to get through that and stick to our core principles," he told the Financial Times. "This is going to be a science, medicine, data decision. This is not going to be a political decision."
CNN has reached out to FDA for comment.
This isn't the first time US officials have discussed authorization for a Covid-19 vaccine before large-scale trials are complete.
This isn't the first time US officials have discussed authorization for a Covid-19 vaccine before large-scale trials are complete.
During a July 30 meeting inside Speaker Nancy Pelosi's office, Treasury Secretary Steven Mnuchin and White House Chief of Staff Mark Meadows raised the possibility of an emergency use authorization for a vaccine before Phase 3 trials were completed. The Financial Times first reported the details of the meeting.
Phase 3 vaccine trials are underway
Two Covid-19 vaccines are currently in Phase 3 trials in the United States -- those made by Moderna and Pfizer/BioNTech -- and two more are expected to begin Phase 3 trials by mid-September. Vaccine makers are seeking to enroll at least 30,000 volunteers so they can tell whether the vaccine is really safe and protects people from infection.
Both already in advanced-stage trials in the United States have enrolled more than half the number of participants needed, US health officials said during a call with reporters on Friday about Operation Warp Speed.
Both already in advanced-stage trials in the United States have enrolled more than half the number of participants needed, US health officials said during a call with reporters on Friday about Operation Warp Speed.
During the call, the health officials said there could be enough data even before 30,000 people are enrolled in a trial, but Operation Warp Speed officials aren't able to see the data yet.
"There is a thing called a Data Safety Monitoring Board, an independent body that is assigned to each clinical trial," Paul Mango, deputy chief of staff for policy at the US Department of Health Human Services, said during the briefing.
"We have no insight into the data until the DSMB says we can look at it. They can come back and say, 'This is not a good vaccine.' They could come back before we even have 30,000 folks enrolled and say 'We have enough. This looks great.' "
Adverse reactions to the vaccine could also trigger the DSMB to stop the trial.
"What we are really looking for is cases -- the number of positive cases from both the placebo and the vaccine group," Mango said.
"Once we get to 150 or so, statistically that is significant regardless of how many enrollees we have in the trial," he added.
"That may be surprising to some, but really the number of events that have to occur ... is relatively small," US Centers for Disease Control and Prevention Director Dr. Robert Redfield added during the call.
Concerns about an 'October surprise' vaccine
Earlier this month, President Trump said he was "optimistic" a vaccine would be ready around Election Day on November 3.
"I believe we'll have the vaccine before the end of the year, certainly, but around that date, yes. I think so," Trump said.
Doctors have worried that just before Election Day, President Trump might pressure the FDA to approve a coronavirus vaccine before it's ready as an "October surprise" to gain votes.
"This just cannot be allowed to happen," Dr. Francis Collins told CNN this month.
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He said if FDA's Hahn approves a vaccine based on flimsy evidence, "he's got a lot of people he'd have to answer to."
Collins said he'd be one of those people, and so would Dr. Anthony Fauci, director of the National Institute of Allergies and Infectious Diseases and a member of the White House Coronavirus Task Force.
Collins said he, Fauci, and others would "certainly make a big noise about not supporting [the vaccine]" if the FDA were to approve it prematurely, adding that the vaccine cannot be approved "on the basis of anything other than science."
