Fast-Tracking A COVID-19 Vaccine Could Be A Double-Edged Sword
The Food and Drug Administration has said it's open to making a COVID-19 vaccine available before phase 3 clinical trials are complete.
Stephen Hahn, commissioner of the Food and Drug Administration, told the Financial Times last week that he was "prepared to authorize a vaccine before phase 3 clinical trials were complete, as long as officials believed the benefits outweighed the risks."
Typically, phase 1 trials involve a small number of volunteers.
"You're asking the question: Is the material safe? That is the primary emphasis of phase one trials, not whether or not it actually works or is efficacious, but whether or not the product is safe," said Ray Goodrich, who directs the Infectious Disease Research Center at Colorado State University.
By phase 2, researchers get a sense of what dosage might be best, while continuing to monitor for safety issues. Goodrich said phase 3 answers a critically important question: Does the vaccine really work? And whereas earlier phases involve dozens or hundreds of subjects, the third phase involves thousands of subjects – maybe tens of thousands.
"Oftentimes you need those large numbers in order to really tell: Is this working? Is it really working? Is it providing a benefit to the individuals who are receiving it?" Goodrich said.
And, he added, the larger scale of phase 3 also helps researchers spot rare side effects that might not have been evident in smaller studies.
He likened fast-tracking a COVID-19 vaccine to stopping a big meteor on a collision course with Earth. Would you just shoot any old missile at it? Or, would you wait, as the meteor got closer and closer, until you were sure you had a missile that would do the job right?
"Are there risks of doing something? Absolutely there are," he said. But there are also risks of doing nothing, too.
"All of that has to be weighed against the current health crisis," said Goodrich, who is involved in developing a vaccine candidate that is currently being tested in animals.
A rushed vaccine could also heighten existing skepticism of its safety. Already only about half of Americans say they would get vaccinated for COVID-19, according to a recent poll from the Associated Press-NORC Center for Public Affairs Research.
Dr. Thomas Campbell said Hahn’s comments may have been misconstrued, as treatments and vaccines are sometimes fast-tracked -- or, conversely, discontinued -- based on how a phase 3 trial is progressing. The determination is made by an independent board called a Data and Safety Monitoring Board, or DSMB.
“There have been recent examples of that,” said Campbell, a virologist and infectious disease specialist with the University of Colorado School of Medicine and UCHealth. “For instance, with remdesivir, there was a phase 3 trial sponsored by the National Institutes of Health and the DSMB monitoring that study found evidence that remdesivir was providing benefit for treatment of severe and critical COVID."
So, he explained, the FDA went ahead and authorized the drug under an Emergency Use Authorization.
Conversely, hydroxychloroquine was touted as effective, but, Campbell said, “in several studies the DSMB recommended stopping the study because there was no benefit.”
Campbell is currently involved in recruiting Colorado patients to a phase 3 trial of the potential Moderna vaccine against COVID-19. Nationally, the study is expected to involve 30,000 people. Campbell said since they started recruiting people at the end of August, that now includes about 80 Colorado residents.
According to the Washington Post, the Moderna vaccine is one of seven candidates that have made it all the way through to Phase Three human trials. On the other end of the spectrum, there are more than 170 being tested in animals.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Boise State Public Radio in Idaho, KUNR in Nevada, the O'Connor Center for the Rocky Mountain West in Montana, KUNC in Colorado, KUNM in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.