Published June 25, 2009
The Cystic Fibrosis Center located in Women and Children’s Hospital of Buffalo, a UB-affiliated teaching hospital, is the first site to begin recruiting patients for a 48-week international clinical trial of a promising investigational treatment for cystic fibrosis (CF).
Drucy Borowitz, MD, professor of pediatrics at UB chief of the Pediatric Pulmonology Division at Women and Children’s Hospital of Buffalo and director of the CF center, heads the Buffalo trial site. A total of approximately 80 sites around the world eventually will be involved in this trial.
Cystic fibrosis is a genetic disease that affects approximately 30,000 people in the U.S. and 70,000 people worldwide. The ‘CF gene’ makes CFTR (cystic fibrosis transmembrane conductance regulator) protein, an ion channel that transports chloride and regulates other ion channels.
Mutations in the CF gene result in defective or missing CFTR proteins in the cell, which may result in the production of thick mucus that clogs the lungs and causes life-threatening lung infections. The median predicted lifespan currently of a person with CF is 37 years.
The Buffalo site of the trial, called STRIVE, will enroll people 12 years-of-age and older who carry a mutation known as G551D in the CF gene. Participants will receive a pill twice a day of either placebo or a drug called VX-770, which is designed to improve the function of defective CFTR proteins at the cell surface.
VX-770 was developed by Vertex Pharmaceuticals Incorporated with support from the Cystic Fibrosis Foundation. The company will be conducting three different VX-770 clinical trials as part of a registration program for VX-770, involving a total of approximately 110 sites.
CF is diagnosed through a “sweat test,” which determines if the body’s perspiration contains abnormally high levels of chloride. “There are more than 1,300 CFTR mutations, grouped into five classes,” said Borowitz. “VX-770 is designed to improve chloride transport for patients with Class III mutations, which cause defective regulation of chloride. We are studying patients with these mutations now, but other drugs are being developed for other classes of mutations.
“In Phase 2 studies, patients with the G551D mutation showed improvements in lung function with VX-770 and, more strikingly, they showed nearly normal sweat chloride after two- and four-week courses with a range of doses,” said Borowitz.
The current study is a Phase 3 trial, the final step before a successful drug may be submitted to the FDA for potential approval.
“The initiation of the VX-770 registration program is a major advancement in our efforts to bring forward a new therapy aimed at treating the underlying cause of CF,” said Robert J. Beall, PhD, president and chief executive officer of the Cystic Fibrosis Foundation.
“This investigational drug represents one of the most promising routes to changing the course of this disease, and we are encouraged with the progress of both VX-770 and VX-809, which recently entered a Phase 2a clinical trial in CF patients.”
In addition to STRIVE, another 48-week Phase 3 trial is recruiting children between the ages of 6 and 12 with the G551D mutation, and a 16-week trial will be conducted for the first time in patients with the most common mutation in CF patients, known as F508del. The CF center also will be participating in the study of patients with the F508del mutation, expected to begin in the third quarter of 2009.