Cystic Fibrosis Drug a Game Changer?

Nov. 2, 2011 -- Hopes are high that a new treatment soon could improve and possibly extend the lives of patients with the inherited disease cystic fibrosis.

In a study appearing in The New England Journal of Medicine, researchers report that the experimental oral drug ivacaftor, formerly known as VX-770, dramatically improved lung function and other symptoms in cystic fibrosis patients with a rare genetic mutation.

Studies are under way to determine if combination therapy with ivacaftor and another experimental drug could do the same thing in most other patients with the genetic disease.

The drugs target the disease process and not just symptoms and disease-related complications, as current cystic fibrosis treatments do.

CF Drug a Potential Game Changer

Cystic Fibrosis Foundation (CFF) president and CEO Robert J. Beall, PhD says he believes the research that led to the drugs will be a game changer for cystic fibrosis and possibly many other genetic diseases.

“This is the first time that an oral drug has been used to treat a basic defect in a genetic disease,” he tells WebMD. “This research could very well open up new treatment horizons for people who suffer from many genetic diseases.”

About 30,000 children and adults in the United States and 70,000 people worldwide have cystic fibrosis. It’s a disease of the glands that produce sweat and mucus, and causes the body to produce very thick, sticky secretions that clog the lungs and keep the pancreas from working optimally.

Symptoms of the disease, caused by a defective gene, include frequent lung infections, wheezing, shortness of breath, coughing, poor growth, and difficulty gaining weight.

Patients also have very salty sweat because their sweat glands are not able to properly conduct chloride. The genetic defect does not allow chloride to properly move in and out of cells, so it builds up in sweat as sodium chloride (salt). Measuring the amount of chloride in sweat has been the standard test for cystic fibrosis for decades.

Fifty years ago, most children with the disease died before they entered kindergarten. Today, thanks to treatments that help control symptoms, the average life span of patients is about 38 years.

Dramatic Improvement in Lung Function

The newly reported study included 161 cystic fibrosis patients as young as age 12 with a specific disease mutation known as G551D. About 4% of patients have the mutation.

All the patients in the study continued taking treatments to control their symptoms. Half also took the experimental oral drug twice a day for 48 weeks, while the other patients took placebo pills.

Over the course of the study, patients taking the experimental drug gained an average of 6 pounds more than the placebo-treated patients. And six months after beginning treatment their lung function had improved by 17%. Patients who took a placebo showed almost no improvement in lung function.