tguyton writes "The good news: the FDA just approved the distribution of the first drug to treat the underlying cause of Cystic Fibrosis, called Kalydeco by Vertex Pharmaceuticals. The bad news: this drug will only affect 4% of patients with the disease in the U.S. From the article: '[Affected patients] with the so-called G551D mutation have a defective protein that fails to balance the flow of chloride and water across the cell wall, leading to the buildup of internal mucus. The vast majority of cystic fibrosis patients have a different genetic defect, in which the protein does not reach the cell wall. Vertex is developing another drug to try and address that problem. Study data for that drug is expected later this year.' Hopefully the research involved will be applicable to finding treatments for other genetic diseases." Further bad news: "...executives said Kalydeco would cost $294,000 for a year's supply, placing it among the most expensive prescription drugs sold in the U.S."