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A new drug treatment based on a genetics discovery from the 80s could dramatically improve the lives of many people with Cystic Fibrosis

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{♫Intro♫} 30 years and two months ago—on September 8, 1989—researchers published three papers describing the gene responsible for cystic fibrosis.

It was a huge breakthrough, and one they hoped would lead to a reliable treatment in no time. Well, it wasn't “no time”, but the discovery has finally led to a drug that dramatically improves the lives of most people with cystic fibrosis.

A new three-drug combination called Trikafta was unveiled last week in a pair of papers in The Lancet and The New England Journal of Medicine. And it's already being called a “game-changer” by medical professionals who don't use that kind of language lightly. In fact, it looks so promising that the US Food and Drug Administration fast-tracked its approval.

And that's all wonderful news for the more than 70 thousand people worldwide that live with the disorder today. Though, the steep cost could prevent some of them from actually receiving it. Back in the first half of the 20th century, when doctors first described and named cystic fibrosis, the cause of the lung and digestive disorder was a mystery.

They knew that children with it had trouble breathing due to unusually thick mucus in their lungs. Thick mucus also made them prone to lung infections and prevented them from breaking down and absorbing nutrients properly... All of which meant they often died before reaching their teen years.

And though we've found ways of reducing the effects of these symptoms, people with. CF still have a life expectancy in their forties. So in 1989, when researchers found the gene responsible, it was a pretty big deal.

They called the gene the cystic fibrosis trans-membrane conductance regulator or CFTR gene, and it codes for a protein that normally allows chloride ions to move in and out of cells. Mutations to this gene make it so the CFTR protein doesn't work, can't find its way to the cell membrane to do its job, or doesn't get made at all. And that explains the thick mucus.

Chloride normally attracts water, so when those ions don't get into the mucus, it gets thicker and stickier. Thicker mucus in the lungs blocks airflow. And its stickiness catches and holds onto nasty stuff like bacteria, making people prone to lung infections which damage the lungs over time.

Meanwhile, in the pancreas, thick mucus blocks digestive enzymes from making their way to the intestines, so the body has a hard time absorbing food and nutrients. Doctors thought the discovery of the CFTR protein would somewhat quickly lead to a general treatment for cystic fibrosis. After all, they now knew the problem.

So all they needed were drugs that fix that problem, like ones get the protein working properly again. But it turns out there are more than seventeen hundred mutations to the CFTR gene that can cause cystic fibrosis. So even though doctors did find drugs that helped fix the protein, they only worked for specific mutations—and none of them seemed to be effective for the most common one.

That's a mutation known as F508del, which causes the CFTR protein to fold wrong. The cell then sees the misfolded proteins as trash and gets rid of them. But this new treatment does work for F508del, and that's what makes it such a huge deal.

Two of the drugs get the proteins to the cell surface before they're destroyed, and the third helps correct the folding so they pump chloride properly. Based on the two clinical trial results published last week, Trikafta is expected to dramatically improve lung function for almost 90% of people with CF. Which is great.

It's not a cure, but improving lung function made a /big/ difference to the people who took it. They reported a much higher quality of life than those who received a placebo. Doctors hope the drug will work so well that their patients can ease up on the lengthy daily therapies they do now to alleviate symptoms.

And reducing the number and severity of lung infections could mean people with CF live longer, especially if the drug is eventually approved for younger children. Right now, though, it's only for people over the age of 12. And the treatment isn't perfect for other reasons.

Like, because the drugs correct the specific issue caused by the F508del mutation, the drug combo won't work for people who don't have it. And, interestingly, that tends to mean people of color as their disorders are more likely to involve other, rarer mutations. Trikafta is also super expensive.

We're talking $311,000 US dollars per year, which obviously, is a lot to pay, especially if you have to pay it for decades. And it probably shouldn't cost that much. Economic review panels have previously slammed Vertex, the company that makes Trikafta, for overpricing their CF drugs by up to seventy-seven percent.

So, Trikafta has the power to change thousands of people's lives—but whether it will depends mostly on insurance companies. And ultimately, the goal is to find something that works for everyone—like delivering bits of RNA directly to lung cells so they produce the right protein in the first place. While Trikafta is a fantastic step in the right direction that many doctors are legitimately stoked about, researchers working on cystic fibrosis say they're going to keep at it until they find a universal treatment—or, even better, a universal cure.

Thanks for watching this episode of SciShow News, produced by Complexly. And we here at Complexly have another bit of news to share—a new[ish] channel! About two months ago, we launched Ours Poetica, which is a co-production between Complexly,.

The Poetry Foundation, and poet Paige Lewis. Ours Poetica brings you a new poem three times a week, read by poets, writers, artists, and sometimes unexpected, yet familiar, voices… like ME! I chose The Raven by Edgar Alan Poe because it's not as creepy as it seems.

It's really this sad, scary, beautiful ode to grief that really resonates with me. So yeah, you can watch it by clicking the link in the description. And while you're there, be sure to check out all the other wonderful poems! {♫Outro♫}.