Vertex Pharmaceuticals has been boosted by the news that European regulators have given the thumbs-up to Kalydeco for the treatment of a rare form of cystic fibrosis.

The European Commission has approved Kalydeco (ivacaftor) for people aged six and older who have at least one copy of the G551D mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. An estimated 1,100 people in Europe have the G551D mutation and the approval comes two months after the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) issued a positive opinion.

The drug was approved in the USA at the end of January and is expensive with a price across the Atlantic of pricing the drug at $294,000 annually. Vertex chief executive Jeffrey Leiden noted that "we're preparing to supply pharmacies throughout Europe…and are working closely with national health authorities to make it available to patients as quickly as possible".

The approval went down well with the European Cystic Fibrosis Society, whose president, Stuart Elborn, said that Kalydeco "is one of the most important advances in the treatment of cystic fibrosis since the discovery of the CF gene in 1989". He added that by treating the underlying cause of the disease in people with the G551D mutation, the drug helped them "breathe more easily, gain weight and resulted in certain improvements in quality of life".

Vertex is also working on a combination of Kalydeco with an investigational treatment called VX-809 but suffered some embarrassment in May when it had to correct previously-announced interim Phase II data for the combo.