Lumacaftor / Ivacaftor

What it is and how it works

Mechanism of Action The CFTR protein is a chloride channel present at the surface of epithelial cells in multiple organs. The F508del mutation results in protein misfolding, causing a defect in cellular processing and trafficking that targets the protein for degradation and therefore reduces the quantity of CFTR at the cell surface. The small amount of F508del-CFTR that reaches the cell surface is less stable and has low channel-open probability (defective gating activity) compared to wild-type CFTR protein. Lumacaftor improves the conformational stability of F508del-CFTR, resulting in increased processing and trafficking of mature protein to the cell surface.

Mechanism class: Cytochrome P450 3A Inducers · Cytochrome P450 2B6 Inducers · Cytochrome P450 2C8 Inducers

Indications

is indicated for the treatment of cystic fibrosis (CF) in patients aged 1 year and older who are homozygous for the F508del mutation in the CFTR gene. If the patient's genotype is unknown, an FDA-cleared CF mutation test should be used to detect the presence of the F508del mutation on both alleles of the CFTR gene. ORKAMBI is a combination of ivacaftor, a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator, and lumacaftor, indicated for the treatment of cystic fibrosis (CF) in patients aged 1 year and older who are homozygous for the F508del mutation in the CFTR gene. If the patient's genotype is unknown, an FDA-cleared CF mutation test should be used to detect the presence of the F508del mutation on both alleles of the CFTR gene. Limitations of Use: The efficacy and safety of ORKAMBI have not been established in patients with CF other than those homozygous for the F508del mutation. Limitations of Use The efficacy and safety of ORKAMBI have not been established in patients with CF other than those homozygous for the F508del mutation .

Dosage and administration (summary)

Age Group Weight Dose Administration 1 through 2 years 7 kg to <9 kg 1 packet of lumacaftor 75 mg/ivacaftor 94 mg granules Mixed with one teaspoon (5 mL) of soft food or liquid and administered orally every 12 hours with fat-containing food 9 kg to <14 kg 1 packet of lumacaftor 100 mg/ivacaftor 125 mg granules ≥14 kg 1 packet of lumacaftor 150 mg/ivacaftor 188 mg granules 2 through 5 years <14 kg 1 packet of lumacaftor 100 mg/ivacaftor 125 mg granules ≥14 kg 1 packet of lumacaftor 150 mg/ivacaftor 188 mg granules 6 through 11 years - 2 tablets of lumacaftor 100 mg/ivacaftor 125 mg (lumacaftor 200 mg/ivacaftor 250 mg per dose) Taken orally every 12 hours with fat-containing food 12 years and …

Contraindications

None. None.

Warnings and precautions

Use in patients with advanced liver disease: ORKAMBI should be used with caution in these patients and only if the benefits are expected to outweigh the risks. If ORKAMBI is used in these patients, they should be closely monitored after the initiation of treatment and the dosage should be reduced. Liver function decompensation, including liver failure leading to death, has been reported in CF patients with pre-existing cirrhosis with portal hypertension.

Pregnancy

Pregnancy Risk Summary There are limited and incomplete human data from clinical trials and postmarketing reports on use of ORKAMBI or its individual components, lumacaftor or ivacaftor, in pregnant women to inform a drug-associated risk.

Storage and supply

Store at 20°C - 25°C (68°F - 77°F); excursions permitted to 15°C - 30°C (59°F - 86°F) .

Source: Lumacaftor And Ivacaftor (Orkambi) — US FDA prescribing information, 2026-03-24, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.