2,300 sign up to be infected with coronavirus. Are human-challenge trials a good idea?

Thousands of volunteers have signed up to be infected with coronavirus in hopes of creating a vaccine faster, an advocacy group says.

So far, nearly 2,400 people say they’ll participate in human-challenge trials for a COVID-19 vaccine, according to 1 Day Sooner, an effort by researchers and experts.

Meanwhile, members of Congress have asked the FDA to consider using the controversial practice to speed up production of a vaccine for the virus.

Human-challenge trials have been conducted for other diseases like malaria and influenza, but some experts worry about using them for coronavirus.

What’s a human-challenge trial?

In human-challenge trials, participants are intentionally infected with a disease to develop a vaccine, according to the World Health Organization. The idea is to accelerate vaccines with more accuracy.

But infecting people with dangerous diseases may contradict the principle held by those in the medical industry to do no harm. Plus, the studies may have limitations in what they actually help researchers understand, according to the WHO.

“Human challenge trials may be safely and ethically performed in some cases, if properly designed and conducted,” WHO guidelines from 2016 say. “Tremendous insight into the mode of action and the potential for benefit in the relevant species – humans – may be gained from challenge trials.”

On Tuesday, U.S. Reps. Bill Foster of Illinois and Donna Shalala of Florida requested that the FDA and U.S. Department of Health and Human Services approve human-challenge trials for COVID-19, if the risk is scientifically rational.

“The enormous human cost of the COVID-19 epidemic alters the optimization of the risk/benefit analysis in favor of more rapid approval and deployment,” the letter said. “Every week of delay in the deployment of a vaccine to the seven billion humans on Earth will cost thousands of lives.”

Why not try?

Some experts are concerned we don’t know enough about coronavirus to intentionally infect people with it.

Matthew Memoli, an immunologist at the U.S. National Institute of Allergy and Infectious Diseases, conducts human-challenge trials for influenza, according to Science magazine. He’s concerned about the long-term effects and serious symptoms of the virus, the news outlet reported.

“Where you’re going to give somebody a virus on purpose, you really want to understand the disease so that you know that what you’re doing is a reasonable risk,” Memoli told Science.

Others are concerned preparing an ethical trial won’t necessarily happen “fast.”

Peter Hotez, a vaccine expert at Baylor College of Medicine, said determining appropriate dosages, ensuring volunteers get effective antiviral treatment and other factors need to be considered, BuzzFeed News reported.

“While I’m sure these timelines can be accelerated, it still won’t be easy to do this very quickly,” Hotez told the news outlet. “It doesn’t mean we shouldn’t do it, it would certainly help down the line, but I don’t see how it happens very fast.”

Arguments for challenge trials

1 Day Sooner, the advocacy group seeking young and healthy volunteers, argues every day without a vaccine costs thousands of lives.

The group says the researchers are likely to try “somewhat unconventional methods” anyway due to the pandemic’s urgency. That includes potentially conducting tests on people more likely to get infected — including health care workers — to better determine whether a vaccine is working.

“We want to recruit as many people as possible who want to do this, and pre-qualify them as likely to be able to participate in challenge trials should they occur,” Josh Morrison, co-founder of 1 Day Sooner, told Nature. “At the same time, we feel that the public policy decisions around challenge trials will be better informed if they highlight the voice of people interested in participating in such trials.”

Stanley Plotkin, a vaccine expert at University of Pennsylvania, and Arthur Caplan, a bioethicist at New York University, published an outline for human-challenge trials in the journal Vaccine.

“Deliberately causing disease in humans is normally abhorrent, but asking volunteers to take risks without pressure or coercion is not exploitation but benefiting from altruism,” Plotkin and Caplan wrote. “We are aware of multiple offers from people willing to volunteer for the challenge studies. As Shakespeare put it, ‘Desperate diseases by desperate measures are relieved.’”

This story was originally published April 23, 2020 at 3:54 PM with the headline "2,300 sign up to be infected with coronavirus. Are human-challenge trials a good idea?."