Ivacaftor / Tezacaftor Dosage

Medically reviewed by Drugs.com. Last updated on Feb 7, 2024.

Applies to the following strengths: 75 mg-50 mg and ivacaftor 75 mg; 150 mg-100 mg and ivacaftor 150 mg

Usual Adult Dose for Cystic Fibrosis

1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally in the morning and 1 tablet (ivacaftor 150 mg) orally in the evening

Comments:

Dosing should be approximately 12 hours apart; tablets should be swallowed whole with fat-containing foods such as those prepared with butter or oils, those containing eggs, cheeses, nuts, whole milk, or meats.
When the genotype is not known, an FDA-cleared cystic fibrosis (CF) mutation test should be used to detect the presence of a CF transmembrane conductance regulator (CFTR) mutation followed by verification with bi-directional sequencing when recommended by the mutation test instructions for use.

Use: For the treatment of patients with cystic fibrosis who are homozygous for the F508del mutation or who have at least 1 mutation in the CFTR gene that is responsive to this combination drug based on in vitro data and/or clinical evidence.

Usual Pediatric Dose for Cystic Fibrosis

6 to less than 12 years; weight less than 30 kg:

Take 1 tablet (tezacaftor 50 mg/ivacaftor 75 mg) orally in the morning and 1 tablet (ivacaftor 75 mg) orally in the evening

6 to less than 12 years; weight 30 kg or more:

Take 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally in the morning and 1 tablet (ivacaftor 150 mg) orally in the evening

12 years or older:
Take 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally in the morning and 1 tablet (ivacaftor 150 mg) orally in the evening

Comments:

Dosing should be approximately 12 hours apart; tablets should be swallowed whole with fat-containing foods such as those prepared with butter or oils, those containing eggs, cheeses, nuts, whole milk, or meats.
When the genotype is not known, an FDA-cleared cystic fibrosis (CF) mutation test should be used to detect the presence of a CF transmembrane conductance regulator (CFTR) mutation followed by verification with bi-directional sequencing when recommended by the mutation test instructions for use.

Renal Dose Adjustments

Mild to moderate renal impairment: No adjustment recommended
Severe renal impairment or ESRD: Use with caution

Liver Dose Adjustments

MILD hepatic impairment (Child-Pugh Class A): No adjustment recommended
MODERATE hepatic impairment (Child-Pugh Class B):

Age: 6 to less than 12 years weighing less than 30 kg: 1 tablet (tezacaftor 50 mg/ivacaftor 75 mg) orally once a day in the morning; no evening dose
Age: 6 to less than 12 years weighing 30 kg or greater: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally once a day in the morning; no evening dose
Age: 12 years or older: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally once a day in the morning; no evening dose

SEVERE hepatic impairment (Child-Pugh C):

Age: 6 to less than 12 years weighing less than 30 kg: 1 tablet (tezacaftor 50 mg/ivacaftor 75 mg) orally once a day in the morning or less frequently; no evening dose
Age: 6 to less than 12 years weighing 30 kg or greater: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally once a day in the morning or less frequently; no evening dose
Age: 12 years or older: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally once a day in the morning or less frequently; no evening dose

If transaminase elevations occur during therapy (i.e, ALT or AST greater than 5 x upper limit of normal (ULN), or ALT or AST greater than 3 x ULN with bilirubin greater than 2 x ULN, dosing should be interrupted and laboratory tests closely followed until abnormalities resolve; following resolution of transaminase elevations consider the benefits and risks of resuming treatment

Dose Adjustments

Concomitant use with Strong CYP450 3A Inhibitors:

Age: 12 years or older: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally twice a week, approximately every 3 to 4 days; no evening doses
Age: 6 to less than 12 years weighing 30 kg or greater: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally twice a week, approximately every 3 to 4 days; no evening doses
Age: 6 to less than 12 years weighing less than 30 kg: 1 tablet (tezacaftor 50 mg/ivacaftor 75 mg) orally twice a week, approximately every 3 to 4 days; no evening doses

Concomitant use with Moderate CYP450 3A Inhibitors:

Age: 12 years or older: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally every other morning alternating with one tablet (ivacaftor 150 mg) orally every other morning on alternate days; no evening dose
Age: 6 to less than 12 years weighing 30 kg or greater: 1 tablet (tezacaftor 100 mg/ivacaftor 150 mg) orally every other morning alternating with one tablet (ivacaftor 150 mg) orally every other morning on alternate days; no evening dose
Age: 6 to less than 12 years weighing less than 30 kg: 1 tablet (tezacaftor 50 mg/ivacaftor 75 mg) orally every other morning alternating with one tablet (ivacaftor 75 mg) orally every other morning on alternate days; no evening dose

Co-administration with Strong CYP450 3A inducers is not recommended
AVOID food or drink containing grapefruit or Seville oranges during treatment

Precautions

CONTRAINDICATIONS: None

Safety and efficacy have not been established in patients younger than 6 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

Take orally in the morning and in the evening (approximately 12 hours apart) with food that contains fat
Tablets should be swallowed whole
A typical cystic fibrosis diet will satisfy the fat requirement; examples of foods that contains fat include: eggs, butter, peanut butter, cheese pizza, and whole-milk dairy products such as whole milk, cheese, and yogurt
Therapy requires 2 different tablets, the morning dose is a combination tablet consisting of tezacaftor and ivacaftor, the evening dose is ivacaftor alone; dose modifications may be needed which may result in omitting the evening dose and taking morning dose less frequently

Missed dose:

If 6 hours or less has passed since dose has been missed: Take dose as soon as possible with fat-containing food
If more than 6 hours has passed since dose has been missed: Skip the missed dose and resume usual dosing schedule

General:

Comparable results were obtained among patients with severe lung dysfunction and those without.
This drug should be administered with food that contains fat to ensure optimal absorption; a typical cystic fibrosis diet should satisfy this requirement.

Monitoring:

Obtain transaminase levels (ALT and AST) prior to initiating therapy, every 3 months for the first year, and annually thereafter; more frequent monitoring should be considered in patients with a history of transaminase elevations.
Ophthalmological exam should be performed at baseline and periodically in pediatric patients.

Patient advice:

Patients should be instructed to read the US FDA-approved patient labeling (Patient Information).
Patients should understand that this therapy requires them to take 2 different tablets, the morning dose is a combination of tezacaftor and ivacaftor, while the evening dose is ivacaftor only; tablets should be taken orally approximately 12 hours apart with a food that contains fat; dose adjustments may be needed which could result in omitting the evening dose and taking the morning dose less frequently.
Patients should be advised that there are major drug interactions that affect how well this drug may work; patients should be instructed to speak with their healthcare provider regarding all medications they are taking or plan to take including over the counter medicines, vitamins, and herbal supplements.
Patients should be instructed to avoid food or drink that contain grapefruit or Seville oranges.
Patients should be instructed to avoid driving or operating hazardous machinery until it is known how this drug affects them; this drug may cause dizziness.