The Race for the Vaccine
By Liv Osby
Even as one of the top coronavirus vaccine trials was halted so researchers could investigate an illness among one of the participants, dozens of other vaccine candidates continue to be studied.
Experts, including those in South Carolina, say it’s likely one of them will be approved in the coming months.
But will Americans want to take it? And will enough take it to make a difference?
More than six in 10 Americans (62 percent) fear the vaccine will be rushed to market without enough attention to safety and effectiveness because of political pressure, according to a new Kaiser Family Foundation poll.
Some 54 percent said they wouldn’t want to get vaccinated if a vaccine were ready before Election Day, while 42 percent said they would.
And about four in 10 say the Food and Drug Administration and the U.S. Centers for Disease Control and Prevention are paying “too much attention” to politics where treatment guidelines and recommendations are concerned.
“Public skepticism about the FDA and the process of approving a vaccine is eroding public confidence even before a vaccine gets to the starting gate,” said KFF CEO Drew Altman.
But scientists say that suspending the AstraZeneca trial of what’s come to be known as the Oxford vaccine, which was developed in England, is a sign that researchers are following procedure.
Dr. Gary Headden leads the AstraZeneca trial at the Medical University of South Carolina, which enrolled just over 100 patients before it was halted. But he told Charleston Business Magazine that from everything he’s seen, investigators are using sound science.
“There’s a lot in the press about the pressure to approve a vaccine,” he said. “But although we are in a pandemic and moving at a little faster pace, I don’t see any shortcuts as to the way the trial is being approached.”
And Dr. Jennifer T. Grier, clinical assistant professor of immunology at the University of South Carolina School of Medicine Greenville, said pausing the AstraZeneca trial indicates that safety protocols are being followed.
Though details have been vague, one patient appears to have suffered neurological symptoms which could have been caused by the vaccine or another reason, she said, adding it’s not known if the patient got vaccine or placebo.
“Because the symptoms were concerning, the trial was paused, as it should have been,” she added, “and investigators that were not involved with the trial reviewed the facts surrounding the event.”
Halted on Sept. 6, the trial resumed in the United Kingdom on Sept. 12. As of Sept. 23, it was still on hold in the U.S., Headen said.
Grier said concern is reasonable if shortcuts were taken, but she doesn’t think that will happen with a coronavirus vaccine.
“Nine of the top vaccine manufacturers have signed a pledge not to seek FDA approval until all safety and efficacy trials are complete, including the current front-runners AstraZeneca, Pfizer and Moderna,” she said. “While this is very good from a community health perspective … it actually benefits the … companies to ensure any vaccine they produce is safe, as an unsafe or ineffective vaccine would erode confidence in the company.”
Meanwhile, Steve Clemons, CEO of Vitalink Research, which is testing the Moderna vaccine in the Upstate, said he doesn’t think a vaccine will be approved before the election whether pressure is put on the FDA or not.
“It’s moving faster than what I’ve seen in previous trials, but the whole point of doing the study is safety and efficacy,” he said. “I still have to believe that the FDA will follow the path that the American population be treated safely.”
Headden said it’s unfortunate that the pandemic has been clouded by “so much politics” - from pressure to produce a vaccine to wearing masks - when “there’s such a need to get this thing under control.”
To reach herd immunity – which occurs when a large enough portion of the community becomes immune – about 70 percent of the population must be vaccinated or infected, Grier said.
Without widespread vaccination, the only route to herd immunity is natural infection, she said, and only about 2 percent of the population has been infected resulting in 200,000 deaths, meaning that attempting to achieve herd immunity through natural infection “would lead to disaster.”
“So it will be extremely important to get people on board with … the vaccine so that we can reach the 70 percent immunity goal while minimizing morbidity and mortality from the virus,” she said.
Vaccines work by introducing something that looks like the disease into the body so the immune system can fight it without putting the person at risk, said Grier. In essence, exposure to a safer version of an infection makes you resistant.
Vaccines are tested in three phases. Phase I is conducted on a small number of people to see if the vaccine can be tolerated. In Phase II, it’s tested on a larger number of people to see if it’s safe and it works. And in Phase III, the vaccine is given to thousands of people who are compared with people who get a placebo to see if it actually prevents the illness.
The word vaccine comes from vaccinia, the Latin word for cow, Grier said. When smallpox was spreading, people noticed that milkmaids weren’t getting infected. The reason was that they had been exposed to the less serious cowpox.
So they began to swab cowpox on the wounds of people who wanted protection, which seemed to work, she said. They got cowpox, but that was better than contracting smallpox.
One of the first markers that shows a vaccine is effective is whether the body has produced proteins known as antibodies, she said. Another piece is T-cells, which help make a stronger antibody response and can kill infected cells before the virus can replicate and take over, she said.
The ideal vaccine will do both, she said.
Medicine uses dozens of vaccines now to combat a wide variety of diseases, Grier said, and still others are in development, including a universal vaccine that works for all strains of flu.
By mid-September, about 180 Covid vaccine studies were underway around the globe and nine were in Phase III trials, according to the World Health Organization. It typically takes years to produce a vaccine, but the timeline is compressed because of the pandemic.
The main candidates for coronavirus vaccine are nucleotide/primarily RNA-based, Grier said, or viral vector-based.
The nucleotide vaccine has pieces of RNA that cause a patient’s cells to make a protein that stimulates the immune system to respond. Moderna and Pfizer are both using this process, she said.
With the viral vector vaccine, a piece of protein is put inside a minimally infectious adenovirus, which causes the common cold, and the immune system responds, she said.
The Oxford-AstraZeneca vaccine uses a chimpanzee adenovirus, she said. Because researchers began working on it after the emergence of Middle East Respiratory Syndrome, or MERS, in 2012, they were ahead of the game.
Most Phase III studies hope to enroll about 30,000 people, a large enough sample to make mathematical assumptions for the general population, Grier said, adding that researchers want to vaccinate health care workers and others at greatest risk first.
“You can’t judge if it works unless it’s being used among people at greatest risk,” said Grier, who volunteered for the Moderna trial but hasn’t heard whether she’s been selected.
Vitalink had such a good response to its recruitment efforts that it had to hire 40 percent more staff, Clemons said.
Founded in 2004, Vitalink has five locations in the Upstate, including Anderson, Greenville and Spartanburg, and a sixth in Columbia, he said.
Though they originally expected to enroll 100 patients at each location, they wound up with 5,000 interested applicants, but will enroll 1,300 to 1,500 in the end, he said.
“People are looking into what clinical trials are so they potentially can get the vaccine before it’s approved and be part of something altruistic,” he said. “They realize they’re doing something for someone other than themselves. They’re part of the fight.”
MUSC hopes to enroll 1,500 as well, said Headden, who adds he’s “pretty optimistic” it will yield good results.
Patients in the Vitalink and MUSC studies get two injections 30 days apart of a vaccine or saline placebo with investigators unaware of who gets which, and will be followed for two years.
Vaccine development is being funded through Operation Warp Speed, a public-private partnership that uses federal money to manufacture vaccines in development so they’re ready to administer once proven effective, said Grier.
And though it’s a financial risk because a vaccine may not be effective, the idea is sound because it saves months of production time and can disburse an approved vaccine much faster, she said.
Grier expects the nation will know by November or December if any of the vaccines now in Phase III trials work. And Headden doesn’t expect one to be approved before the end of the year with vaccination beginning in early 2021.
“Normally it takes a lot longer,” said Grier. “But in this case, it might be worth a trade-off to start with slightly less information if there is a positive effect for a vaccine, because people are dying.”
To learn more about the Vitalink research, go to covidvaccinesc.com.
To learn more about the MUSC trial, go to https://research.musc.edu/clinical-trials/