Scientists Plan To Start Human Trials Testing CRISPR Soon The powerful gene-editing technique is moving out of the lab and into the clinic. Trials will use CRISPR to try to treat a variety of diseases, ranging from cancer and blindness to blood disorders.

Scientists Plan To Start Human Trials Testing CRISPR Soon

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We have news of a new way to attack cancer. NPR has learned that doctors have used a powerful new gene editing technique in cancer treatment in the United States for the first time. That news is just the latest about the technique called CRISPR. Some news has troubled much of the world, as when a Chinese scientist announced last year that he used CRISPR to create genetically modified babies. Now this less controversial news. NPR health correspondent Rob Stein sat down with Rachel Martin.

RACHEL MARTIN, BYLINE: OK. Rob, let's start off big-picture. Remind us all what CRISPR is, exactly.

ROB STEIN, BYLINE: CRISPR, basically, is an entirely new kind of genetic engineering that gives scientists the power to edit DNA, make precise changes in DNA much more easily than ever before. So scientists think CRISPR could revolutionize medicine, the way we prevent and treat many diseases, by doing things like fixing genetic defects or modifying the genes inside cells or basically turning them into drugs.

MARTIN: So is that what that Chinese scientist was doing?

STEIN: He used CRISPR to edit the genes inside human embryos, and that means any change he made could be passed down for generations to come. In this case, for medical treatments, the modifications are only being made in the DNA of individual patients. So it doesn't raise all those "Brave New World" scenarios about re-engineering the human race.

MARTIN: OK. So explain what is happening now.

STEIN: Yeah. So what's happening now is we finally reached the moment when CRISPR is moving out of the lab and into the clinic, around the world, for medical treatments. Until now, there's only been a small number of studies where scientists have tried to use CRISPR to treat disease, and they've almost all been in China to treat cancer. Now scientists in Europe, the United States and Canada are launching a wave of studies to try to use CRISPR to treat a variety of diseases. Here's Fyodor Urnov. He's a scientist at the Altius Institute for Biomedical Sciences in Seattle.

FYODOR URNOV: 2019 is the year when the training wheels come off and the world gets to see what CRISPR can really do for the world in the most positive sense.

MARTIN: OK. So what does that mean? What diseases are we talking about here?

STEIN: Yeah. So the first are blood disorders, like sickle cell disease and a similar condition, a genetic condition known as beta thalassemia. And in fact, the first beta thalassemia patient was just recently treated in Germany, and more are about to get their blood cells CRISPR-ed soon at a second hospital in Germany. Then there'll be patients treated in Toronto, in London. And the first sickle cell disease patients could start to get the DNA in their blood cells edited in this country really soon.

And there's yet another noteworthy study, and that's a study that's going to try to treat an inherited form of blindness. And the reason that's noteworthy is because this would be the first time scientists try to use CRISPR to edit the genes inside the human body. The other studies involve removing cells from patients, editing them in the lab and then infusing the modified cells back into patient's body.

MARTIN: Wow. So those are all very important conditions and diseases. What about cancer, though?

STEIN: Well, Rachel, one study involving CRISPR is underway in the United States to treat cancer. It's at the University of Pennsylvania. And I just learned that two patients have been treated there for multiple myeloma and sarcoma. But several other cancer studies may be starting soon involving CRISPR this year in places like Texas and New York.

MARTIN: OK. So all of that is exciting. All of that seems like very positive, good news. But is there a dark underbelly here? I mean, are there concerns about it?

STEIN: Well, sure. You know, whenever you try something completely new and something as powerful as this, people always get a little bit nervous that something could go wrong. Everybody remembers the early days of gene therapy when some patients, you know, even died. Here's Laurie Zoloth. She's a bioethicist at University of Chicago I talked to about this.

LAURIE ZOLOTH: Every human on the planet should hope that this technology works. But it might work. It might not. It's unknown. This is an experiment. So you do need exquisite layers of care, and you need to really think in advance with a careful ethical review how do you do this sort of work.

MARTIN: All right. So do we have any sense of when we will know if these CRISPR treatments are working?

STEIN: Yeah. So all these studies are really early. They're very preliminary. And they're aimed primarily at testing whether these experimental CRISPR treatments are safe. That said, the scientists are looking for clues about whether they might be helping patients. So we could get a glimmer of that sometime later this year or maybe early next year.

MARTIN: NPR health correspondent Rob Stein. Thanks so much, Rob.

STEIN: Thanks, Rachel.

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