The U.S. Food and Drug Administration (FDA) approved Kalydeco for the treatment of a rare form of cystic fibrosis in patients aged six years and older who have the specific G551D mutation in the CFTR gene.

Cystic fibrosis (CF) is a serious genetic disorder affecting the lungs and other organs that ultimately leads to an early death. It is caused by mutations in a gene that encodes for a protein called Cystic Fibrosis Transmembrane Regulator (CFTR) that regulates ion and water transport in the body. The defect in chloride and water transport results in the formation of thick mucus that builds up in the lungs, digestive tract and other parts of the body leading to severe respiratory and digestive problems, as well as other complications such as infections and diabetes.

CF, which affects about 30,000 people in the United States, is the most common fatal genetic disease in the Caucasian population. About four percent of those with CF, or roughly 1,200 people, are believed to have the G551D mutation.

In patients with the G551D mutation, Kalydeco, a pill taken two times a day with fat-containing food, helps the protein made by the CFTR gene function better and as a result, improves lung function and other aspects of CF such as increasing weight gain.

"Kalydeco is an excellent example of the promise of personalized medicine -- targeted drugs that treat patients with a specific genetic makeup," said FDA Commissioner Margaret Hamburg in a statement.

According to the FDA, the most common side effects of Kalydeco include upper respiratory tract infection, headache, stomach ache, rash, diarrhea, and dizziness.

VietNamNet/Xinhuanet