Canadian scientists' insights into Kalydeco for a rare form of cystic fibrosis

Scientists at the Hospital for Sick Children in Toronto, Canada, have established that a drug recently approved by the US Food and Drug Administration and the European Commission, Vertex Pharmaceuticals (Nasdaq: VRTX) Kalydeco (ivacaftor or VX-770; The Pharma Letter July 30 and February 1), to treat a rare form of cystic fibrosis works in an unconventional way. Their results reveal new possibilities for treating various forms of cystic fibrosis.

Cystic fibrosis is an inherited disease afflicting about 70,000 people around the world. Cystic fibrosis patients carry a defective gene that disables or destroys its protein product, which normally regulates the transport of ions across cell borders. When that transport is disrupted, the viscosity of the mucus coating certain organs becomes too thick. A characteristic feature of the disease is thick mucus build-up in the air passages, which causes difficulty breathing and recurring infections.

While the FDA approved the drug to ease breathing in people with cystic fibrosis caused by a particular mutation in the CFTR protein (the acronym is short for cystic fibrosis transmembrane conductance regulator), exactly how VX-770 worked in those patients was unknown.