Two new studies on a pair of triple-drug treatments may represent the first effective treatment for most patients with cystic fibrosis, a chronic, incurable condition that is frequently fatal. Researchers have been striving for a consistently effective treatment for years, and two new studies published in New England Journal of Medicine may offer an answer, according to ScienceNews.org.
Both approaches combine three drugs, taken over four weeks in the studies. Both were found to be safe, with tolerable side effects, and both improved lung function in patients with the most common mutation that causes cystic fibrosis, which accounts for 90 percent of cases.
This and other mutations affect a gene called CFTR, either rendering it defective or stopping the body from producing the protein at all.
The CFTR protein normally lines airways in the lungs and regulates how cells take in and expel water, as well as charged chloride ion particles. With no properly functioning CFTR protein, sticky mucus fills the lungs, holding pathogens such as bacteria in place. Cystic fibrosis patients suffer from chronic lung infections as a result, which damage their respiratory systems over time and ultimately shorten their lifespans due to lung failure.
While patients can live up to 50 years, lives are also cut short before the age of 30. The condition affects 30,000 people in the US.
The new treatments are based on ivacaftor, a drug approved in 2012 to treat cystic fibrosis resulting from a much rarer mutation. In those patients, ivacaftor improved the protein’s effectiveness, improving lung function and quality of life.
“They are in the hospital much less. The way they feel on a day-to-day basis is substantially improved,” said University of Alabama at Birmingham School of Medicine pulmonologist Steven Rowe, who co-authored one of the two new studies.
In both of the new clinical trials, ivacaftor was paired with a corrector drug called tezacaftor, as well as a third corrector drug that varied in each trial. Both approaches improved lung function in patients, from about 60 percent of normal function up to between 70 and 74 percent. Lung functioning was measured with a test determining how much air can be quickly, forcefully exhaled by the patient in one second.
Another coauthor, Jennifer Taylor-Cousar, a pulmonologist with Denver’s National Jewish Health, said:
“It’s the most exciting thing we’ve seen. It will hopefully be life-changing for 90 percent of people with cystic fibrosis.”
The treatments will require further clinical testing before becoming available.