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  • United Kingdom has given approval to a trial

  • that will expose healthy volunteers to COVID-19.

  • Infection is guaranteed

  • with a so-called challenge trial.

  • Challenge trial.

  • Challenge trial.

  • As the pandemic progressed over the last year,

  • you may have heard this term challenge trial come up.

  • The idea was that by deliberately exposing people

  • to the virus, you could help speed up the development

  • of a vaccine, and it turns out a lot of people

  • were up for this.

  • Everybody feels terrible right now.

  • Here's something that may help the world

  • be a little bit better, so I was like, great,

  • that sounds good to me.

  • Let me sign up right now.

  • Ultimately, challenge trials did not end up being used

  • to develop the vaccines that are now in circulation,

  • but now, researchers in the UK are turning

  • to the challenge method, saying it will allow them

  • to test the long-term effectiveness of the vaccines

  • and learn more about the disease overall.

  • It's restarted a controversy in the scientific community

  • over the safety, efficacy and morality of the practice.

  • I spoke to some very smart people on both sides

  • of the argument,

  • in an attempt to answer a question with big implications

  • for humanity's future.

  • Okay, so we're here to talk about human challenge trials,

  • but I guess, first let's talk about typical vaccine trials.

  • How do typical vaccine trials work?

  • Yeah, so once a vaccine candidate has been studied

  • in animals and in the laboratory,

  • it moves into human studies,

  • the idea is that once you're vaccinated

  • with either a placebo of the actual candidate,

  • you're exposed in society to the pathogen,

  • and we want to see that most of the infections

  • and disease occurred in people with the placebo,

  • to determine that the vaccine

  • is actually protective and efficacious.

  • So with a human challenge study,

  • we deliberately infect humans, human volunteers,

  • and look at, essentially, what happens to them.

  • You say I've got the viral agent, COVID, whatever it is,

  • and I'm going to give it to people.

  • This is Art Caplan.

  • He's a researcher at NYU,

  • who's pretty firmly in the pro-challenge trial column.

  • Well, historically vaccines are tested in large trials.

  • Usually you're talking 30, 40, 50, 60,000 or more subjects.

  • You could spend six, seven, eight years trying to get data.

  • A challenge study basically is a way to speed up

  • the trial process.

  • You may be able to get answers as quickly as exposing 500,

  • 600 people, maybe over a period of six months to a year.

  • So are human challenge trials new

  • or have they been done before?

  • Human challenge trials are not new.

  • Scientists have been doing them for quite a long time,

  • decades, looking at various diseases, malaria, cholera,

  • influenza are some of them.

  • Walter Reed did it, as a matter of fact,

  • with his malaria experiments in Cuba.

  • They deliberately let mosquitoes bite them to get malaria,

  • to test antidotes.

  • Assumingly, again, they don't want to kill you,

  • although people have died in challenge studies.

  • We have a tradition in space medicine of saying,

  • "Gee, I wonder how long people can survive

  • "extreme gravitational forces.

  • "Let's put 'em in a centrifuge until they pass out."

  • So there are many areas of medicine, healthcare,

  • even public health,

  • where we do expose people to risk deliberately,

  • in order to learn.

  • This is the infamous trolley problem in bioethics,

  • which is should you sacrifice one person

  • to save five people?

  • This is Liza Dawson, the chief of bioethics

  • at the Walter Reed Army Institute of Research.

  • She's not really opposed to challenge trials,

  • but where COVID is concerned,

  • she's basically in the anti column.

  • One of the issues is that we have less ability

  • to predict what will happen to people as a consequence

  • of COVID infection, something like 10 to 20% of,

  • depending on the numbers,

  • have longterm consequences of COVID infection.

  • That's not to be sneezed at,

  • and people of all ages seem to be susceptible

  • to longer-term consequences of COVID.

  • We are rolling the dice that something terrible might happen

  • or something fairly bad might happen to people

  • in these trials.

  • Well, I do understand the critics

  • and some of their points of view,

  • it's never easy to defend deliberately giving someone

  • something that makes them sick.

  • That violates a core norm of medical ethics, do no harm,

  • but I'm not really buying into the it causes more harm

  • to do a challenge study.

  • It feels psychologically different

  • to give somebody a disease, as opposed to saying,

  • "Gee, I don't know how you got it.

  • "Maybe it was on the subway

  • "or maybe you should've worn a mask

  • "or maybe a new variant appeared."

  • We may feel psychologically, we didn't do it, nature did it.

  • Nonetheless, at the cemetery, they don't care.

  • You're relying on nature to infect you

  • but it's not like people aren't exposed.

  • I'm not sure that that's significantly morally better

  • than just saying, I'll give you the disease

  • and we'll get a faster answer.

  • And there are a lot of volunteers who feel the same way.

  • The organization, One Day Sooner,

  • which advocates for people's right to participate

  • in challenge trials,

  • says it's had almost 40,000 people contact them,

  • offering to take part if such a trial were to be conducted.

  • Two of those volunteers are Lena Jewler,

  • a recent graduate of Johns Hopkins, and Gavriel Kleinwaks,

  • a PhD student in Colorado.

  • Safe to say, they're both in the pro column.

  • So speaking personally,

  • why would you be willing to be part of a challenge trial?

  • I think, initially, I was looking at this as a person

  • who does human subjects research,

  • and a person who likes to participate

  • in human challenge research,

  • so one of the cool things about being a student at Hopkins

  • is that you have access to participate

  • in this really cool research,

  • and I've always found that fascinating, just as a person,

  • to participate, to say, okay,

  • I'm contributing to the science

  • that may help someone else the road, and then,

  • the challenge aspect of it,

  • I was really swayed by this argument

  • of this is so much more efficient,

  • this is so much more effective.

  • I would say the very first place my mind went was...

  • So I'm Jewish, and in our philosophical traditions,

  • it said that to save a single life,

  • it's as if you've saved an entire world.

  • In the argument for challenge trials,

  • the original argument back in March,

  • it was estimated that developing a vaccine...

  • Every day sooner that you develop a vaccine

  • saves 10,000 lives,

  • and I thought that that's amazing.

  • I would do whatever it took to develop a vaccine

  • one day sooner, which is why the organization

  • is called that.

  • We all know what it means to donate your time.

  • We all know what it means to donate your money,

  • but this was an opportunity I felt to donate health,

  • to try to share some of my health with others.

  • So there are reasonable arguments on either side

  • of the ethics debate and a lot of people are willing

  • to take the risk,

  • but some offer a different kind of criticism

  • of challenge trials,

  • that they wouldn't actually accomplish their goal

  • of speeding up vaccine development.

  • That's the big beef put forward by Charles Weiier,

  • a Canadian bioethicist.

  • He says the current UK study is the perfect example

  • of just how long challenge trials can take.

  • What they're doing,

  • so they've spent a number of months

  • developing the challenge strain,

  • so making sure they've got a stable strain,

  • where they haven't introduced mutations

  • through the manufacturing process.

  • The second step is what they're just embarking on now

  • to actually figuring out the protocol

  • for how they're gonna administer this virus,

  • and so they're just beginning that process now,

  • with incremental steps of increasing dose of virus.

  • Each of those steps is going to take at least a month,

  • and so we're many months away from them being at the point

  • where they can even test the vaccine.

  • The advocates have challenged studies by and large.

  • They haven't talked about all this preparatory work

  • that needs to be done.

  • Even from the first article that was published about this,

  • they talked as if next week, we could just start doing this.

  • Right, you just pump a room full of COVID-19

  • and then everybody gets it.

  • Yeah, right, and of course,

  • these studies are much more complicated than that.

  • And then there's the fact that we've got the current slate

  • of COVID-19 vaccines in record time,

  • without using challenge trials.

  • The reason why we got a vaccine so quickly

  • was because of a decade's worth of work

  • on related coronaviruses that cause SARS

  • and that cause MERS, and I think we had the genome

  • of SARS-CoV-2, the novel coronavirus,

  • published on January 10th, I think, of 2020.

  • Three days later, we had our first candidate vaccine.

  • 63 days later, that vaccine was tested for the first time

  • in human beings.

  • By September of last year,

  • we had six large phase three trials

  • planning to involve 280,000 people.

  • The monumental size of the achievement here

  • would be difficult to overstate.

  • Well, that's traditional vaccine development

  • with new technology and it just highlights my point.

  • Challenge studies are just the wrong technology

  • for a rapidly moving pandemic.

  • But some still see challenge trials

  • playing a crucial role in the pandemic, ironically,

  • precisely because we now have working vaccines.

  • As soon as things start to look very promising,

  • and we basically are in a situation where those people

  • who are in a large scale trial, let's just use COVID,

  • are gonna start to say, wait a minute,

  • I don't want to be in the placebo group anymore,

  • I want to drop out,

  • and you can't finish the study ethically.

  • You've got to let those people know

  • you're in the placebo group.

  • You can be pretty certain

  • that nearly everybody will drop out

  • because you're not going to hang around in the placebo group

  • are very likely, so the studies that we have undergoing,

  • that are underway now, of COVID vaccines, are falling apart,

  • because people are dropping out of them left and right,

  • and so we're not going to get the answers that we might want

  • to things like how long does this vaccine last,

  • in terms of protection,

  • or do we know whether it's protecting us

  • against new variants of the virus that appear.

  • Some also see challenge trials as a path

  • to developing new vaccines

  • that improve on the existing ones.

  • Obviously, at this point,

  • we've got three approved vaccines in the US,

  • and maybe eight or nine total globally,

  • but there's still a lot of benefit to these sorts of trials.

  • We can expand the total pool of how many different types

  • of vaccines we have available, and that's important,

  • because a lot of the vaccine candidates we have now,

  • like the MRNA vaccines, they're hard to transport,

  • they take two doses,

  • all of these things that if we continue to try new vaccines,

  • we can find better vaccines that are easier to distribute

  • and that has a lot of equity implication.

  • We can get those to rural areas,

  • different countries with less infrastructure.