Britain Moves Toward Ethically Controversial COVID-19 Vaccine Trial The British government has announced plans for a coronavirus vaccine challenge trial. Volunteers will receive an experimental vaccine and be exposed to the virus to test its efficacy.

Britain Moves Toward Ethically Controversial COVID-19 Vaccine Trial

Britain Moves Toward Ethically Controversial COVID-19 Vaccine Trial

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The British government has announced plans for a coronavirus vaccine challenge trial. Volunteers will receive an experimental vaccine and be exposed to the virus to test its efficacy.


One way to know if a coronavirus vaccine works is to give that vaccine to healthy people and then deliberately expose them to the virus. This is called a challenge study, and they're done for other illnesses. The British government is planning to start doing them for four COVID, but there are serious ethical questions here. Listen to Arthur Caplan talk about it. He's a medical ethicist at NYU School of Medicine.

ARTHUR CAPLAN: One of the sort of odd features ethically some people would say, well, you can't give people a disease that you can't cure them of it if they get it in order to test a vaccine. That's just - do no harm is our principle, and you're breaking it.

KING: NPR science correspondent Joe Palca has been following this one. Good morning, Joe.

JOE PALCA, BYLINE: Good morning, Noel.

KING: All right. So let's suss this out. In other vaccine trials, you give people the experimental vaccine and then you send them out into the world and you wait for them to get COVID naturally. So basically, nature does the dirty work. Infection rates are going up in the U.K. So why would there be this push to deliberately infect people with COVID?

PALCA: Well, I think that's a question that a lot of ethicists and others are asking right now. But there are different things that you learn from these different kinds of trials. The big trials tell you something about populations and you learn about whether the vaccine is working in the natural setting. But you don't learn the kinds of specifics that you can learn from a trial where you know the person is getting infected. You know exactly when it's happening. You know exactly when they get the vaccine compared to when they're exposed to the virus. You learn things about how their body is responding over time. And then there are other things that you can do with these kinds of challenge studies that you just can't do in a natural world experiment. For example, if you want to bring somebody back into the lab and expose them a second time, either to see how long the vaccine works for or how well it works over time, you know, that's something you can't do with the population, with one of these large studies. So instead of - and if you've got a new vaccine that you want to test, do you want to really recruit 10,000, 30,000 more people and then do the whole big test again? Or do you want an answer that you can get in a relatively short space of time? There are advantages.

KING: There are advantages. And as you just said, one of the advantages is speed, which I think every human alive would be invested in that. So when do we expect the results of this challenge trial?

PALCA: Well, I think the results are still certainly a ways off. But first, they have to get permission to do them. In the U.K., there's something called the Medicines and Healthcare Products Regulatory Agency, which is the U.K. equivalent of the Food and Drug Administration. And that body has said that they're going to form their own special ethics committee to consider the ethics of this. Yes, there are questions about it. I think the idea is to try to do this kind of experiment in a way that would put the people who volunteered in the least amount of damage. And there are a lot of people who volunteered. There's an organization that's in this country and the U.K. that has begun to say, hey, if you want to sign up, give us your name and we'll let people know. So there's a lot of people who've lined up to do this.

KING: No kidding. So is there any chance we'd see something like this happen in the U.S.?

PALCA: Well, there are no formal plans for this in the U.S., but the National Institute of Allergy and Infectious Diseases has signed a contract with a lab to actually produce a virus that they could use in such a study. And this is a virus that was taken from somebody who got sick but not very sick. So they're hoping that this is a strain of the virus or a version of the virus that maybe will make people sick but doesn't make them likely to get too sick.

KING: OK. NPR's Joe Palca. Thanks, Joe.

PALCA: You're welcome.

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