It won’t be pleasant, but it could help prove quickly if
a Covid-19 vaccine works.
Mar 25, 2020
A group of academics say that 100 altruistic young people
should volunteer to get a vaccine for Covid-19 and then be infected with the
coronavirus on purpose.
The idea of such a “challenge trial” is controversial but
could speed testing of a vaccine by months, according to a proposal
posted online, offering fast evidence that a shot works or doesn’t.
“We need fresh ideas to get out of the #COVID19 dilemma
of sacrificing the economy, health care system, or both,” tweeted Marc
Lipsitch, a Harvard University epidemiologist who cosigned the proposal with
Nir Eyal, a bioethicist at Rutgers University, and Peter Smith, a statistician
from the London School of Hygiene & Tropical Medicine.
Some experts believe a vaccine is the best hope to end
the epidemic. One candidate
created by Moderna Therapeutics of Cambridge, Massachusetts, is
already being given to healthy volunteers in Washington state in an initial
safety test.
No one, though, has yet had virus squirted up their nose
on purpose, something that is ethically dubious under most circumstances. The
drawback is obvious, the authors admit: “Challenging volunteers with this live
virus risks inducing severe disease and possibly even death.”
Yet the risk could be worth it for society, they think,
since trying to infect vaccinated people on purpose might be the quickest way
to learn whether a vaccine works.
One expert in challenge trials, Myron Levine, of the
University of Maryland, says he doesn’t believe the idea is merited yet.
According to statistics released by the
Centers for Disease Control and Prevention, people between 20 and 44
accounted for 20% of those hospitalized for Covid-19 in the US, with about 1 in
750 dying.
“Is this something you would allow your loved one to
participate in?” asks Levine. “Ask yourself that.”
Exposing people to a germ can be an acceptable way to do
scientific research—and Levine says he’s been doing
challenges since 1970, with diseases including cholera. He says the studies
are considered permissible in certain scenarios. One is where people get a
weakened, or attenuated, version of a virus. Another is if there is a drug cure
available in case the vaccine flops and things go south. But there’s no drug
treatment yet for the dangerous pneumonia associated with Covid-19.
Despite that, the three authors of the new proposal, none
of whom are doctors, say they think that younger adults, who usually don’t
suffer serious forms of the illness, could make an informed choice to be the
guinea pigs that help save the world from Covid-19. That’s especially true
since they might get infected anyway.
The scientific trio offer a sketch of how they think it
could be done. First, the youthful volunteers would be subjected to a two-week
quarantine to make sure they were virus free. After that, they’d be given the
virus and then observed. During the study they would remain isolated in “a
secure and comfortable setting.” Doctors could then measure if they had any
virus in their throats, and how long it took them to develop any symptoms.
“The required size of such studies would depend upon the
endpoints chosen, but they might require of the order of 100 volunteers,” the
three speculate. “Any volunteers in whom infection was confirmed would receive
excellent care for COVID-19, including priority for any scarce life-saving
resources, in state-of-the-art facilities.”
The problem with vaccines is that it typically
takes at
least 18 months to test them and get supplies ready. And a big chunk
of the R&D time is given to a phase 3 trial—the main event, in which
hundreds or thousands would get the vaccine and others would not, in an attempt
to prove that those who are vaccinated don’t get the disease or have fewer
symptoms if they do.
According to Smith, Lipsitch, and Eyal, giving a vaccine
to people and then infecting them on purpose could speed up that process and
“may be an acceptable way to bypass Phase 3.”
Levine agrees a challenge trial “could cut the time.”
However, if Covid-19 continues to afflict the world, the advantage of a
contagion study may not be as great as it seems. With lots of people getting
infected anyway, a trial that is both speedy and ethical should be possible to
organize.
Already, steps are being taken to shrink the time a
vaccine will take. Moderna and the National Institutes of Health reportedly
began safety studies with its vaccine before
finishing the typical animal studies. According to the Boston
Globe, Moderna’s CEO, Stéphane Bancel, also told bankers that the company
could seek emergency approval from Washington to give its coronavirus vaccine
to some people this fall.
“It is possible that under emergency use, a vaccine could
be available to some people, possibly including health-care professionals,”
Bancel said, according to a filing with the Securities and Exchange Commission.
It’s likely that if a challenge trial occurs, plenty of
volunteers would sign up. After all, first responders, EMTs, health-care
workers, and even grocery store clerks are already putting themselves at risk
of Covid-19 by staying on the job.
“It may seem impermissible to ask people to take on risk
of severe illness or death, even for an important collective gain,” the authors
of the challenge proposal write. “But we actually ask people to take such risks
for others’ direct gain every time we ask volunteer firefighters to rush into
burning buildings.”
