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A remarkable new drug appeared on the market this past year. It's called Kalydeco, and it's designed to treat people with a lung disease called cystic fibrosis. While not quite a cure, the drug is extremely effective for some patients. NPR's Joe Palca has this story of how Kalydeco came to be.
JOE PALCA, BYLINE: A good starting point for the story of Kalydeco is August 24, 1989.
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LINDA WERTHEIMER, BYLINE: Scientists announced at a news conference today that they have found the gene that causes cystic fibrosis.
PALCA: That's how Linda Wertheimer began NPR's coverage of the story. It was the early days of gene hunting in 1989, and the CF gene was a big prize. Cystic fibrosis is the most common genetic disease in Caucasians. When people inherit a damaged form of the CF gene, a critical protein inside cells doesn't work properly. As a result, sticky mucus builds up in a patient's lungs, causing infections and making it hard to breathe.
My colleague Michelle Trudeau did the story of the gene discovery on ALL THINGS CONSIDERED back in 1989. She talked to scientists who predicted that a genetic test for cystic fibrosis was just around the corner. But they said there was more.
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MICHELLE TRUDEAU, BYLINE: With the discovery of the gene, different drugs can be tested to see if any of them will get the defective protein to do what it's supposed to do. So an effective treatment is now within reach as well.
PALCA: The genetic test did come fairly quickly.
DR. FRED VAN GOOR: But it wasn't until 20 years later that we were able to find drugs that directly target the underlying cause of cystic fibrosis. So it was a long time between the discovery of the gene and the discovery of Kalydeco.
PALCA: Fred Van Goor led the team at what is now Vertex Pharmaceuticals that developed Kalydeco.
GOOR: We tested over 600,000 chemicals in cells with the defective protein that causes cystic fibrosis.
PALCA: One of those chemicals ultimately became a successful drug. But it was a long slog. The chemical had to be modified so patients could take it by mouth and so it would last the right length of time in a patient's body. From the start, Van Goor and his colleagues knew there was a problem with Kalydeco. It only works on a small subset of people with cystic fibrosis. They have to have a particular mutation in the cystic fibrosis gene or the drug is of little use. But for people who do have that mutation, the drug's impact is stunning.
Emily Schaller was in one of the early studies of Kalydeco. As part of the study, researchers first gave her a placebo, then switched her to the real drug. She knew within days that something was different.
EMILY SCHALLER: I was with my brother in Florida, and we were walking down the street. I was - I took a deep breath in. And when I took a deep breath in and I let it out, and I didn't cough. But not only did I not cough, I just felt like my lungs were clear, and that something huge had happened. It was just something I had never felt in my life before.
PALCA: Schaller isn't cured. She still has a damaged CF gene. The only way to fix that would be to replace the damaged gene with a healthy one, a process called gene therapy. Although it seems simple in theory, in practice, gene therapy has been incredibly difficult to accomplish. Schaller isn't particularly bothered by that.
SCHALLER: Everyone talks about curing a disease, cure cystic fibrosis, cure these other diseases. But Kalydeco controls CF, you know, at the basic defect. So I'm OK with the other C word, control, because I'm living it and it's - I've never felt better in my life.
PALCA: But even finding drugs that control genetic diseases has been extremely difficult, that's why Kalydeco is so noteworthy. Scientists hope there will soon be many more drugs that are based on understanding the genetics of the disease, but those drugs will likely be expensive. A year's supply of Kalydeco can cost around $300,000. Joe Palca, NPR News, Washington.
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