New Approach Shows Promise for Cystic Fibrosis

Researchers say a widely used antifungal drug may hold promise for treating people with cystic fibrosis, a life-threatening genetic disorder that causes serious damage to the lungs. In studies using human cells and animal models, the researchers found that the medication, called amphotericin, helps lung cells function in a way that could make it easier for patients to fight chronic bacterial lung infections that are a hallmark of the disease. The findings from the study, which was supported in part by NHLBI, will appear in the journal Nature.

If human studies validate the findings, the use of the drug could be good news to the more than 30,000 people in the United States and 70,000 worldwide who live with cystic fibrosis, a disease with no cure and few treatment options. It holds special promise for a subset of patients, about 10 percent of the people with cystic fibrosis, who do not respond to any treatment.

“The really exciting news is that amphotericin is a medicine that’s already approved and available on the market,” said Dr. Martin D. Burke, leader of the study and professor of chemistry at the University of Illinois in Champaign. “We think it’s a good candidate.”

Cystic fibrosis is caused by a defect in a gene called CFTR (cystic fibrosis transmembrane conductance regulator). This gene normally makes a protein that controls or channels the movement in and out of cells of such materials as salt, bicarbonate and water—all of which are important to normal lung function. In people with cystic fibrosis, however, the defective gene makes a protein that is itself defective, causing the accumulation of acidic and sticky mucus that not only clogs the lungs and makes it hard to breathe, but also makes the lungs vulnerable to bacterial infection.

While some treatments are currently available, they are limited because different people have different types of mutated proteins, and because 10 percent of people with cystic fibrosis make no protein at all. But amphotericin, Burke said, has the potential to work regardless of the kind of mutation, and even when the protein is missing.