Ivacaftor for Cystic Fibrosis and the G551D-CFTR Mutation
Ivacaftor for Cystic Fibrosis and the G551D-CFTR Mutation
The recommended dose of ivacaftor in adults and children 6 years of age and older is 150 mg every 12 hours. The dose should be taken with high-fat foods to increase absorption. Examples include eggs, butter, peanut butter, or cheese pizza. Eating grapefruit or Seville oranges, or drinking their juices, should be avoided while taking ivacaftor. The dose of ivacaftor should be reduced to 150 mg once daily in patients with moderate hepatic impairment (Child-Pugh Class B). Ivacaftor should be used with caution in patients with severe hepatic impairment (Child-Pugh Class C), at a dose of no more than 150 mg once daily and with consideration of dosing even less frequently. Patients receiving concomitant therapy with a strong CYP3A4 inhibitor should receive ivacaftor 150 mg twice weekly, while patients taking a moderate CYP3A4 inhibitor should be treated with ivacaftor 150 mg once daily. No dose adjustment is needed for patients with mild to moderate renal impairment. Use of ivacaftor in patients with severe renal impairment has not been studied.
Dosing Recommendations
The recommended dose of ivacaftor in adults and children 6 years of age and older is 150 mg every 12 hours. The dose should be taken with high-fat foods to increase absorption. Examples include eggs, butter, peanut butter, or cheese pizza. Eating grapefruit or Seville oranges, or drinking their juices, should be avoided while taking ivacaftor. The dose of ivacaftor should be reduced to 150 mg once daily in patients with moderate hepatic impairment (Child-Pugh Class B). Ivacaftor should be used with caution in patients with severe hepatic impairment (Child-Pugh Class C), at a dose of no more than 150 mg once daily and with consideration of dosing even less frequently. Patients receiving concomitant therapy with a strong CYP3A4 inhibitor should receive ivacaftor 150 mg twice weekly, while patients taking a moderate CYP3A4 inhibitor should be treated with ivacaftor 150 mg once daily. No dose adjustment is needed for patients with mild to moderate renal impairment. Use of ivacaftor in patients with severe renal impairment has not been studied.
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