KNOXVILLE, Tenn. — In August 2020, WBIR's Robin Wilhoit got her first dose of Pfizer's experimental COVID-19 vaccine during a trial with Volunteer Research Group.
She was one of more than 40,000 volunteers around the world to participate in the vaccine trial.
On July 28, Pfizer announced that new data from its first clinical trial showed that protection provided by the COVID-19 vaccine diminishes slightly in the months following the second dose.
The drug company is making the case for a booster shot, but the Centers for Disease Control said a third dose is not needed at this point.
Now, it has started a new clinical trial to test these boosters, and Robin is one of 10,000 people from the original study rolling up their sleeves for the third time.
The trial will determine whether a third dose, a booster, is needed to provide more protection from the virus.
Dr. Bill Smith with American Medical Response (AMR) is heading up the trial in Knoxville.
"It’s a much smaller trial. We already know about the basic safety of the vaccine now. So this is actually targeting the response, particularly the antibody response to a booster," he said.
Participating in this booster trial is a lot like the initial study. It begins with filling out and reviewing lots of forms, answering a long list of questions, giving vials of blood and then taking a COVID-19 test.
Once everything checks out, volunteers are given the all-clear for the third shot.
"This particular booster is the same vaccine as what was in the first one," Smith said.
It's an mRNA vaccine like the original doses and comes with similar side effects like fever and pain at the injection site.
Smith said half of the participants receive the real vaccine and the other half a placebo. Only the trial researchers know who got which shot.
Over the next year, they’ll compare the two groups to see if a booster shot is necessary for everyone to stay protected from COVID-19. They will compare the number of people who develop COVID-19 in each group.
Smith said, at this time, immunity appears to remain high in people who are already vaccinated.
"For how long are their antibody levels going to be effective? We don’t know that answer yet because we’re still less than a year from when we did the first vaccines, but we’re continuing to follow antibody levels in the groups that had the early vaccines," he said.
Researchers will know in months whether a third dose is needed. But right now, Smith said the best way to protect yourself is to get the first two shots, especially as variants emerge.
"We are still in a pandemic, and everything we are seeing now suggests that we’re going to see an additional surge," he said. "How bad this is going to be is still yet to be determined, but the more people who are vaccinated then the less severe this surge is going to be."
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