A new study has confirmed that Ivacaftor, a bioavailable drug taken orally, is an effective treatment for patients with cystic fibrosis.
Cystic fibrosis is a genetic disease that affects thousands of people worldwide. It is diagnosed in about a thousand patients in America per year. Although close to 10 million people are carriers, the gene that constitutes expression of cystic fibrosis-associated proteins is recessive, meaning that the gene must be passed down by both parents to be expressed. Found in the long arm of the seventh chromosome, this gene is responsible for mutant proteins that interfere with our cells' ability to regulate chloride concentration.
The protein, called cystic fibrosis transmembrane conductance regulator (CFTR), is an epithelial ion channel that manages absorption and secretion of salt and water in the lungs, gastrointestinal tract, sweat glands and pancreas. Patients with cystic fibrosis carry a mutation in the gene, which not only alters the function of the protein, but also reduces the amount of the protein actually expressed on the cell membrane, where ion channels typically reside.
When the channels are mutated, and the chloride concentration is not balanced to physiologically optimal measures, the mucous that is produced by the body becomes thick, dry and gluey. This blocks the digestive enzymes necessary to degrade food for our digestive system to absorb into our body for health and reduces lung capacity as the mucous layering in the lungs become thick.
Cystic fibrosis patients typically experience what's equivalent to the breathing capacity of having only one lung. Unfortunately, as the symptoms progress, these patients begin to breathe with half the lung capacity, then none at all.
Prior to recent investigation of Ivacaftor's potential to treat cystic fibrosis, patients had to ingest pancreatic enzyme pills, supplementary vitamins and as much calries as possible because the flow of digestive enzyme is blocked.
They also had to abide by stringent measures to loosen the mucous in their lungs by performing manual chest therapy at least twice a day. During each therapy session, a member of the family or a doctor pounds, or "percusses," on the fourteen different regions of the body to loosen the mucous and help the patient cough it up.
These patients have hope for a new type of therapy, which is orally consumable. The Ivacaftor is designed to increase the time of which the CFTR ion channel is left open for chloride ions to flow through.
The new Ivacaftor study was conducted from June 2009 to January 2011. With a sample of 161 cystic fibrosis patients, some of whom were treated with Ivacaftor and others with a placebo, the study confirmed an overall decrease in chloride in the sweat of patients who received the drug.
Dysfunction of the CFTR protein is characterized by salty sweat. Salt is composed of sodium and chloride ions. Thus, the decrease in chloride in sweat indicated a normalized regulation in chloride absorption.
The discovery of Ivacaftor's effect on the CFTR gene is a milestone in the field of cystic fibrosis. As more studies confirm the effectiveness of the drug, Ivacaftor can serve as an effective drug to ameliorate cystic fibrosis symptoms.
