The United States will know by the end of the year or the beginning of 2021 whether a coronavirus vaccine is safe and effective, Dr. Anthony Fauci, the nation's leading infectious diseases doctor, said Monday.
Multiple vaccine candidates are being studied, and "if things go the way it looks like they're going, one of these will enter phase 3 at the end of July," he said, referring to the final phase of clinical trials needed to determine whether a drug works.
Other vaccine candidates will enter phase 3 trials after July, and "we hope that by end of this year, or the beginning of 2021 we will at least have an answer whether the vaccine or vaccines - plural - are safe and effective," Fauci, who is the director of the National Institute of Allergy and Infectious Diseases, said.
He took part in a conversation with Dr. Francis Collins, director of the National Institutes of Health, on Facebook Live on Monday as new cases of COVID-19 continue to surge in the U.S.
"The current state is really not good," Fauci said, adding that two days ago, there were 57,500 new cases in the U.S.
"We are still knee-deep in the first wave of this," he said. Referring to the recent increases in cases, he went on, "I would say this would not be considered a wave, it was a surge or a resurgence of infections superimposed upon a baseline, Francis, that really never got down to where we wanted to go."
Much of the conversation focused on vaccine development.
To ensure that a vaccine will be available soon after clinical trials are complete, Fauci said, the National Institutes of Health is working with companies to start making doses of the drug before it's known whether it works or not.
And if the vaccine doesn't turn out to be safe and effective? Those doses will just have to be thrown out, he said. "But that is a financial risk, it is not a risk for safety, nor is it risk for scientific integrity," he added.
Collins acknowledged that the government's name for the development of a coronavirus vaccine — dubbed "Operation Warp Speed" — may give some the impression that scientists may be cutting corners for safety.
"I want to assure everybody — because you and I are in all these conversations, often many times a day and late into the night — that there will be no compromising on the principles of safety and efficacy," he said. "Whatever we come up with in a few months is going to be just as rigorously tested as any vaccine ever has been."
The phase 3 trials will include 30,000 people, half of whom will receive the vaccine and half of whom will not. The trials will take place in areas where there are high levels of transmission, possibly including locations outside the U.S.
The researchers will also aim to include people in high-risk groups.
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Fauci said that he and Collins are "making sure that the trials are quite well represented by the individuals who are most susceptible, not only to infection because of certain circumstances in their life, but also the fact that they are more prone to complications because of underlying comorbidities."
He also acknowledged that we don't yet know the answer to how long protection from the vaccine will last. "We're going to assume that there's a degree of protection, but we have to assume that it's going to be finite protection," Fauci said, adding that follow-up research will be needed to determine if and when people need a booster.
Collins struck an optimistic tone on vaccine development. "You’re saying this is a pretty good virus for a vaccine to work. It has the ability where natural infection does seem to be protective. It doesn't seem to mutate too rapidly compared to some others. Is that fair?"
"That is fair," Fauci agreed. "It’s an RNA virus and as we know, RNA viruses mutate, but the functional consequence of that mutation so far doesn’t look to be impressive."
Collins and Fauci ended the conversation urging the American people to stick with the public health guidance.
"It will end," Fauci said. "We will get through this. Hang in there. It will end, we promise you."