April 1, 2019Rare Diseases
Cystic fibrosis (CF) 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 CF, 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% of people with cystic fibrosis make no protein at all.
According to an article published in Nature (March 2019), amphotericin B, a widely-used antifungal drug may hold promise for treating people with CF. In studies using human cells and animals models, the authors found that amphotericin B 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. According to the authors, 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 CF. It holds special promise for that 10% subset of patients who do not respond to any treatment.
For the study, using lung tissue from patients with CF, as well as pig models of CF, the authors found that amphotericin B spurred a host of changes associated with improved lung function -- restoration of pH levels, improved viscosity, and increased antibacterial activity, among others. The authors also noted that amphotericin B can be delivered directly to the lungs to avoid common side effects. However, the authors added that more experimental studies are needed before the drug can be deemed safe to treat CF.