Could a vaccine developed at Duke University prevent future coronavirus pandemics?
Duke University researchers are developing a vaccine that could provide protection against multiple kinds of coronaviruses, according to a study published last week in Nature, a leading scientific journal.
The vaccine, which was developed at Duke’s Human Vaccine Institute, uses nanoparticles to show the immune system 24 copies of a specific part of the virus’ spike protein that attaches to human cells. An additional substance promotes the creation of antibodies that attack that part of the virus.
“It’s very similar to Velcro. So if you think of one hook and loop, that’s a pretty weak interaction. But if you can put one hook and loop together multiple times in multiple copies, that becomes a really strong interaction,” Dr. Kevin Saunders, the Human Vaccine Institute’s director of research, said during a Monday press briefing.
Saunders, lead author of the paper in Nature, said the vaccine was based on the institute’s work with an HIV vaccine.
The Duke team tested the nanoparticle vaccine by injecting it into macaque monkeys, finding that it provides total protection against SARS-CoV-2, the coronavirus that causes COVID-19. Additionally, the vaccine created antibodies against SARS, bat coronaviruses and the more contagious variants of the virus that causes COVID-19.
“What we’ve all learned now with this particular pandemic, that now is the time to prepare for the next one so that we can have vaccines on the shelf or vaccines that can be developed extremely rapidly and deployed very rapidly,” said Barton Haynes, the director of Duke’s Human Vaccine Institute, during Monday’s briefing.
Having such a vaccine available would let governments and health officials limit the spread of a virus, Hayes added, potentially preventing it from evolving into a pandemic.
During a May 13 White House briefing, Dr. Anthony Fauci discussed the possibility of a vaccine that protects against multiple kinds of coronaviruses.
Fauci, the director of the National Institutes of Allergy and Infectious Disease and White House senior adviser on the pandemic, pointed to the Duke research as “potentially exciting” and called it “an important proof of concept.”
The experiments were conducted in nonhuman primates, Fauci cautioned. “Nonetheless,” he said, “this is an extremely important proof of concept that we will be aggressively pursuing as we get into the development of human trials.”
How the vaccine works
While the Johnson & Johnson, Moderna and Pfizer COVID-19 vaccines all target the SARS-CoV-2 spike protein, the Duke vaccines targets only the small piece at the top that attaches to the host cell, Saunders said. Some sites on that piece are found across multiple coronaviruses.
“It’s the generation of this multi-component response that gives you activity not only against SARS-CoV-2, but also activity against other coronaviruses,” Saunders said.
The Duke team is particularly worried about coronaviruses that are circulating among bats, Saunders added, because both SARS-CoV-1 and SARS-CoV-2 seem to have started in the creatures before jumping into humans.
Researchers also found that the Pfizer and Moderna vaccines could provide some protection against coronaviruses other than SARS-CoV-2.
To test the nanoparticle vaccine, they created an mRNA vaccine that they said was similar to the Moderna and Pfizer formulas. In the monkeys, those mRNA vaccines provided some antibodies against the animal coronaviruses and SARS-CoV-1, Saunders said.
“The nanoparticle vaccine had an enhanced response compared to those, but their responses weren’t zero so there was some level of antibody response there,” Saunders said.
But the vaccine will not protect against all coronaviruses. For instance, it would not protect against the coronaviruses that cause the common cold or against the virus that causes the Middle East Respiratory Syndrome.
Researchers can change the components in the nanoparticle vaccine, though, potentially protecting against other groups of coronaviruses.
“Really the next stage here is to start to modify the vaccine so that it broadens its coverage,” Saunders said.
The Human Vaccine Institute has already replied to a National Institutes of Health request for proposals calling for the development of vaccines that address multiple coronaviruses, Haynes said. And, he added, the institute plans to apply for NIH funds that would help with the manufacture of coronavirus vaccines for Phase 1 clinical trials.
“I think the federal government is very, very interested in moving this forward,” Haynes said.
This story was originally published May 17, 2021 at 2:25 PM.