Ivacaftor and cystic fibrosis
The FDA approved ivacaftor drug is used in the treatment of cystic fibrosis in patients aged 6 years or older and who have one of the following mutations: G551D, G1244E, G1349D, G178R, G551S, S1251N, S1255P, S549N or S549R in at least one allele of the CFTR gene. It is also indicated in the treatment of patients with cystic fibrosis 18 years of age and older with a R117H mutation in the CFTR gene.
Ivacaftor is a potentiator of the CFTR protein (Cystic Fibrosis Transmembrane Conductance Regulator). The pharmac increases the opening of the CFTR channel to enhance chloride transport in the specified channel opening mutations with a reduced probability of channel opening compared to normal CFTR.
Cautions should be taken in patients with severe renal impairment or end-stage renal disease. Assess risk / benefit in severe hepatic impairment.
Precautions in concomitant use with moderate and potent CYP3A inhibitors or inducers.
In cases of patients with increased aminotransferases (perform liver function tests before starting treatment, every 3 months during the first year and then annually), discontinue treatment.
In addition, be careful in the prescription in patients with ALAT or ASAT greater than 5 times the normal upper limit.
Ivacaftor treatment is not recommended in transplant patients.
There are no data on its use in children younger than 2 years with a channel-opening mutation (class III), nor in children under 18 years with a R117H mutation in the CFTR gene.
GENE OR REGION STUDIED