Cystic fibrosis (CF) is a life-threatening genetic disease, which primarily affects the lungs and digestive system. An estimated 30,000 children and adults in the US and 70,000 worldwide have CF. At present, no cure exists; thus, a significant amount of current research is focused on a curative treatment for the disease. The latest breakthrough was announced on June 24 by Vertex Pharmaceuticals Inc. The pharmaceutical manufacturer announced that it would seek regulatory approval later this year for lumacaftor, an experimental cystic-fibrosis drug, which in combination with another CF medication, produced a statistically significant improvement in patients' lung function compared with placebo in two late-stage studies.
Vertex noted that the two studies of lumacaftor in combination with ivacaftor (Kalydeco) that showed statistically significant improvements in lung function in individuals aged 12 and older with CF)who have two copies of the F508del mutation. (Researchers have identified more than 1,800 mutations in the CF gene. Different CF mutations are grouped into several different classes or types, based on the way the mutations affect the key protein (called CFTR) produced by the CF gene.) The study comprised for treatment arms with different drug regimens. At the end of the treatment, all four 24-week combination treatment arms in the studies achieved their primary endpoint of average absolute improvement in lung function from baseline compared to the placebo. Average absolute improvements in lung function ranged between 2.6 and 4.0 percentage points from baseline, compared to the placebo. The average relative improvements ranged from 4.3-6.7%.
Overall, the combination treatments were well tolerated. The most common adverse events, regardless of treatment group, were flare-ups in lung problems such as cough, headache and increased sputum. However, the symptoms caused some study participant to discontinue treatment: 4.2% of patients who received the combination regimens discontinued treatment because of adverse events compared to 1.6% of those who received placebo. More than 1,000 patients have been enrolled in a rollover study to receive a combination regimen.
Based on the results of the studies, in the fourth quarter of 2014, Vertex plans to submit regulatory applications for approval in a number of nations, including a New Drug Application (NDA) in the US and Marketing Authorisation Application (MAA) in Europe for individuals with CF aged 12 and older who have two copies of the F508del mutation.
”On average, people with CF who have two copies of the F508del mutation lose nearly 2% of their lung function each year, underscoring the urgent need for new medicines that address the underlying cause of this disease” explained Bonnie Ramsey, MD, Professor of Pediatrics, University of Washington School of Medicine, Director of the Center for Clinical and Translational Research at Seattle Children's Research Institute and a lead Principal Investigator for one of the studies. She added, “These data showed consistent evidence of clinical benefit in lung function and other measures of the disease. The significant improvements in pulmonary exacerbations are particularly important given the potential for these events to result in hospitalizations, permanent lung damage and the need for additional treatment with antibiotics and other medicines.”
According to the Cystic Fibrosis Foundation, individuals with CF, a defective gene and its protein product cause the body to produce unusually thick, sticky mucus that clogs the lungs and leads to life-threatening lung infections. It also obstructs the pancreas and stops natural enzymes from helping the body break down food and absorb vital nutrients. In the 1950s, few children with CF lived to attend elementary school. Since then, tremendous progress in understanding and treating CF has led to dramatic improvements in the length and quality of life for those with CF. Many people with the disease can now expect to live into their 30s, 40s, and beyond.
Quick Facts about CF
- In the United States, approximately 1,000 new cases of CF are diagnosed each year.
- More than 75% of people with CF are diagnosed by age two.
- Nearly half of the CF population is age 18 or older.