Kalydeco

Kalydeco, brand name for ivacaftor, is a CFTR potentiator used to treat cystic fibrosis in people with certain CFTR mutations that respond to potentiation. It was developed by Vertex Pharmaceuticals and was first approved by the U.S. Food and Drug Administration in 2012 for patients aged 6 years and older with gating mutations such as G551D. Ivacaftor works by increasing the probability that the CFTR chloride channel remains open, improving chloride transport across cell membranes, which helps rehydrate mucus in the airways and other tissues.

The drug is used in patients with CFTR mutations that allow the CFTR protein to reach the cell surface but function poorly. Over time, regulatory approvals have broadened to include additional gating mutations and younger age groups in several regions. It is not effective for CF patients whose mutations do not respond to potentiation.

In clinical trials, ivacaftor improved lung function as measured by FEV1, reduced sweat chloride, and lowered pulmonary exacerbation rates in responders. It has also shown benefits in quality of life and weight in some patients. Effectiveness depends on the specific mutation.

Ivacaftor is taken orally twice daily with fat-containing meals, with dosing tailored to age and weight.

Common adverse effects include headache, upper respiratory infections, and nasal congestion. Serious risks include elevations in liver enzymes and rare liver injury. Drug interactions with strong CYP3A inhibitors or inducers may require dose adjustments or discontinuation.

Related therapies include other CFTR modulators such as lumacaftor/ivacaftor and tezacaftor/ivacaftor, used for different mutation profiles.