CFTR gene encodes for cystic fibrosis transmembrane conductance regulator protein (CFTR), which is a member of the traffic adenosine 5’-triphosphase (ATPase) family. CFTR is critical regulator of fluid and ion transports, and it plays an important host defense role in the airway.1 Autosomal recessive mutations in the CFTR gene can cause cystic fibrosis (CF), a life-shortening disease affecting >70,000 people worldwide. Ivacaftor is the first US Food and Drug Administration (FDA)-approved drug on the market that targets a specific CFTR defect.2,3 A negative/normal test result does not rule out the presence of other possible pathogenic variants in these gene.
Ivacaftor treatment is recommended only in CF patients who are either homozygous or heterozygous for the G551D-CFTR variant, and aged 6 and older. The latest CPIC guideline indicates that Ivacaftor is not recommended to patients with no G551D-CFTR variant.4