Right now scientists are trying to accomplish something that was inconceivable a decade ago: create a vaccine against a previously unknown virus rapidly enough to help end an outbreak of that virus. In this case, they’re trying to stop the spread of the new coronavirus that has already infected tens of thousands of people, mainly in China, and given rise to a respiratory condition now known as COVID-19.
Typically, making a new vaccine takes a decade or longer. But new genetic technologies and new strategies make researchers optimistic that they can shorten that timetable to months, and possibly weeks — and have a tool by the fall that can slow the spread of infection.
What’s the urgency?
“Vaccines are really our most successful tool to prevent an infectious disease,” says David Weiner, executive vice president and director of the Vaccine & Immunotherapy Center at the Wistar Institute in Philadelphia.
It used to take a long time to make vaccines, because scientists had to isolate and grow the virus in the lab. But now, it’s possible to skip that step altogether and build a vaccine based on a virus’ genetic sequence.
Chinese scientists made that genetic sequence from the new coronavirus public in early January, just weeks after the first infections with the virus were reported. That prompted several labs to start work on building a vaccine.
Vaccines work by teaching an individual’s immune system to recognize an invading virus and neutralize it. The vaccine that Weiner and his colleagues are developing is what’s called a DNA vaccine.
They’ll first turn pieces of the new coronavirus’ genetic code (which is RNA) into complementary snippets of DNA. These snippets will then be injected into someone’s skin, where they will be taken up by skin cells. The skin cells will then turn those DNA sequences into proteins identical to the ones a virus would produce, and those will be what “teaches” the immune system to recognize the new virus.
Weiner and his colleagues are in the process of determining which viral sequences produce the best “teachers.”
This isn’t Wistar’s first stab at rapid vaccine development. Weiner and his team worked on a vaccine for Ebola after an outbreak of that virus in 2014.
Including the initial time needed for animal testing and human safety testing, “We were able to go from no vaccine to a vaccine tested in the clinic in about 18 months — 15 to 18 months,” he says. They also made a vaccine against the coronavirus that causes Middle East respiratory syndrome, after an outbreak in South Korea. “And we were able to design and develop and move into the clinic in 11 months.”
Weiner says he’s hoping to halve that time with the vaccine they are making against the new coronavirus.
Keith Chappell at the University of Queensland in Brisbane, Australia, thinks he can do even better. He, too, has a vaccine that’s based on the virus’ genetic sequence. The Queensland team has come up with an approach it calls the molecular clamp. It works by improving the body’s immune response to certain viral proteins.
“Our goal was to be able to hit 16 weeks from sequence information to having a product that is shown to be safe and effective [in lab tests] and is ready for administration to the first humans,” Chappell says.
Right now, Chappell and his colleagues are also trying to figure out which genetic sequences will be most effective at helping the immune system recognize the coronavirus.
“Next steps will be moving into animal models for testing and also working out how to scale up to get to the levels that would be required in humans and beyond,” he says.
Both Chappell’s team in Australia and Weiner’s team in Philadelphia, in collaboration with the pharmaceutical company Inovio, are getting financial support from a fairly new organization called CEPI, the Coalition for Epidemic Preparedness Innovations. CEPI is a global partnership of public, private and philanthropic organizations; it’s also supporting efforts at the biotech companies Moderna and CureVac.
Among other vaccine efforts worldwide, the pharmaceutical giant Johnson & Johnson is working on a vaccine, and GSK has also offered to help new vaccine efforts. Researchers at Imperial College London have developed a vaccine that’s already being tested in animals, and vaccine efforts are also reportedly underway in China.
CEPI CEO Richard Hatchett says the organization was created when people realized that an Ebola vaccine had been under development for a decade and it still took more than a year to get it to people when the 2014 Ebola outbreak occurred in western Africa.
“There were a number of enlightened global public health leaders who said, ‘You know, that shouldn’t happen. We should have some kind of an organization to develop vaccines against epidemic diseases,'” he says.
Even in the rosiest of scenarios, Hatchett says, once the vaccine is in hand, it still needs to get to the people who need it, and that takes time — at least weeks to months, depending on the urgency.
Naturally, public health officials would like to have a vaccine as soon as possible. If the coronavirus outbreak pattern is anything like those of flu outbreaks, it will tend to taper off when the weather gets warmer and pick up as winter approaches and people spend more time indoors.
“We are making very aggressive efforts in the hopes of having a vaccine available — some form of vaccine available, potentially, as early as this fall,” Hatchett says.
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