Lumacaftor and ivacaftor
Lumacaftor and ivacaftor Uses, Dosage, Side Effects, Food Interaction and all others data.
Ivacaftor (also known as Kalydeco or VX-770) is a drug used for the management of Cystic Fibrosis (CF). It is manufactured and distributed by Vertex Pharmaceuticals. It was approved by the Food and Drug Administration on January 31, 2012, and by Health Canada in late 2012. Ivacaftor is administered as a monotherapy and also administered in combination with other drugs for the management of CF.
Cystic Fibrosis is an autosomal recessive disorder caused by one of several different mutations in the gene for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein, an ion channel involved in the transport of chloride and sodium ions across cell membranes. CFTR is active in epithelial cells of organs such as of the lungs, pancreas, liver, digestive system, and reproductive tract. Alterations in the CFTR gene result in altered production, misfolding, or function of the protein and consequently abnormal fluid and ion transport across cell membranes. As a result, CF patients produce thick, sticky mucus that clogs the ducts of organs where it is produced making patients more susceptible to complications such as infections, lung damage, pancreatic insufficiency, and malnutrition.
Prior to the development of ivacaftor, management of CF primarily involved therapies for the control of infections, nutritional support, clearance of mucus, and management of symptoms rather than improvements in the underlying disease process or lung function (FEV1). Notably, ivacaftor was the first medication approved for the management of the underlying causes of CF (abnormalities in CFTR protein function) rather than control of symptoms.
Lumacaftor is a drug used in combination with Ivacaftor as the fixed dose combination product Orkambi for the management of Cystic Fibrosis (CF) in patients aged 6 years and older. Cystic Fibrosis is an autosomal recessive disorder caused by one of several different mutations in the gene for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein, a transmembrane ion channel involved in the transport of chloride and sodium ions across cell membranes of the lungs, pancreas, and other organs. Mutations in the CFTR gene result in altered production, misfolding, or function of the CFTR protein and consequently abnormal fluid and ion transport across cell membranes. As a result, CF patients produce thick, sticky mucus that clogs the ducts of organs where it is produced making patients more susceptible to infections, lung damage, pancreatic insufficiency, and malnutrition. Lumacaftor improves CF symptoms and underlying disease pathology by aiding the conformational stability of F508del-mutated CFTR proteins, preventing misfolding and resulting in increased processing and trafficking of mature protein to the cell surface.
Results from clinical trials indicated that treatment with Orkambi (lumacaftor/ivacaftor) results in improved lung function, reduced chance of experiencing a pulmonary exacerbation, increased weight gain, and improvements in CF symptoms. This data has been heavily scrutinized, however, with clinical trials showing only modest improvements despite a hefty yearly cost of $259,000 for Orkambi. Improvements in lung function (ppFEV1) were found to be statistically significant, but minimal, with only a 2.6-3.0% change from baseline with more than 70% of patients failing to achieve an absolute improvement of at least 5%.
A wide variety of CFTR mutations correlate to the Cystic Fibrosis phenotype and are associated with differing levels of disease severity. The most common mutation, affecting approximately 70% of patients with CF worldwide, is known as F508del-CFTR, or delta-F508 (ΔF508), in which a deletion in the amino acid phenylalanine at position 508 results in impaired production of the CFTR protein, thereby causing a significant reduction in the amount of ion transporter present on cell membranes. When used in combination with Ivacaftor as the fixed dose combination product Orkambi, lumacaftor is specific for the management of CF in patients with delta-F508 mutations as it acts as a protein-folding chaperone, aiding the conformational stability of the mutated CFTR protein. Consequently, lumacaftor increases successful production of CFTR ion channels and the total number of receptors available for use at the cell membrane for fluid and ion transport. The next most common mutation, G551D, affecting 4-5% of CF patients worldwide, is characterized as a missense mutation, whereby there is sufficient amount of protein at the cell surface, but opening and closing mechanisms of the channel are altered. Treatment of patients with G551D and other rarer missense mutations is usually managed with Ivacaftor (Kalydeco), as it aids with altered gating mechanisms by potentiating channel opening probability of CFTR protein.
| Trade Name | Lumacaftor and ivacaftor |
| Generic | Ivacaftor + lumacaftor |
| Type | Oral |
| Therapeutic Class | |
| Manufacturer | |
| Available Country | United States |
| Last Updated: | September 19, 2023 at 7:00 am |
Uses
Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator used alone or in combination products to treat cystic fibrosis in patients who have specific genetic mutations that are responsive to the medication.
When used as monotherapy as the product Kalydeco, ivacaftor is indicated for the management of CF in patients age 2 years and older who have a mutation in the CFTR gene that is responsive to ivacaftor potentiation. Ivacaftor received expanded approval in May 2017 for the following 33 CFTR mutations: E56K, P67L, R74W, D110E, D110H, R117C, R117H, G178R, E193K, L206W, R347H, R352Q, A455E, S549N, S549R, G551D, G551S, D579G, S945L, S977F, F1052V, K1060T, A1067T, G1069R, R1070Q, R1070W, F1074L, D1152H, G1244E, S1251N, S1255P, D1270N, and G1349D.
When used in combination with the drug lumacaftor as the product Orkambi, ivacaftor is indicated for the management of CF patients age 6 years and older who are shown to be homozygous for the F508del mutation in the CFTR gene.
When used in combination with tezacaftor in the product Symdeko, it is used to manage CF in patients 12 years and older who have at least one mutation in the CFTR gene or patients aged 12 or older who are shown to be homozygous for the F508del mutation.
When used in combination with tezacaftor and elexacaftor in the product Trikafta, it is indicated for the treatment of cystic fibrosis in patients 12 years of age and older who have at least one F508del mutation in the CFTR gene.
Lumacaftor is a protein chaperone used in combination with ivacaftor for the treatment of cystic fibrosis in patients who are homozygous for the F508del mutation in the CFTR gene.
When given in combination with Ivacaftor as the fixed dose combination product Orkambi, lumacaftor is indicated for the treatment of cystic fibrosis (CF) in patients age 6 years and older who are homozygous for the F508del mutation in the CFTR gene.
Lumacaftor and ivacaftor is also used to associated treatment for these conditions: Cystic Fibrosis (CF)Cystic Fibrosis (CF)
How Lumacaftor and ivacaftor works
A wide variety of CFTR mutations correlate to the Cystic Fibrosis phenotype and are associated with differing levels of disease severity. The most common mutation, affecting approximately 70% of patients with CF worldwide, is known as F508del-CFTR or delta-F508 (ΔF508), in which a deletion in the amino acid phenylalanine at position 508 results in impaired production of the CFTR protein, thereby causing a significant reduction in the amount of ion transporter present on cell membranes. Ivacaftor as monotherapy has failed to show a benefit for patients with delta-F508 mutations, most likely due to an insufficient amount of protein available at the cell membrane for interaction and potentiation by the drug. The next most common mutation, G551D, affecting 4-5% of CF patients worldwide is characterized as a missense mutation, whereby there is sufficient amount of protein at the cell surface, but opening and closing mechanisms of the channel are altered. Ivacaftor is indicated for the management of CF in patients with this second type of mutation, as it binds to and potentiates the channel opening ability of CFTR proteins on the cell membrane.
Ivacaftor exerts its effect by acting as a potentiator of the CFTR protein, an ion channel involved in the transport of chloride and sodium ions across cell membranes of the lungs, pancreas, and other organs. Alterations in the CFTR gene result in altered production, misfolding, or function of the protein and consequently abnormal fluid and ion transport across cell membranes . Ivacaftor improves CF symptoms and underlying disease pathology by potentiating the channel open probability (or gating) of CFTR protein in patients with impaired CFTR gating mechanisms. The overall level of ivacaftor-mediated CFTR chloride transport is dependent on the amount of CFTR protein at the cell surface and how responsive a particular mutant CFTR protein is to ivacaftor potentiation .
Lumacaftor improves CF symptoms and underlying disease pathology by aiding the conformational stability of F508del-mutated CFTR, resulting in increased processing and trafficking of mature protein to the cell surface. More specifically, lumacaftor acts as a protein-folding chaperone, preventing misfolding of CFTR ion channels and consequent destruction during processing in the endoplasmic reticulum.
Toxicity
LD50 information is not readily available. There have been no reports of overdose with ivacaftor, but when given with tezacaftor, the highest clinical dose lead to diarrhea and dizziness. Provide supportive measures in cases of a suspected overdose. No antidote is available at this time.
The most common side effects (occuring in >5% of patients during clinical trials) associated with the use of Orkambi include dyspnea, nasopharyngitis, nausea, diarrhea, upper respiratory tract infection, fatigue, respiration abnormal, blood creatine phosphokinase increased, rash, flatulence, rhinorrhea, and influenza.
Volume of Distribution
After oral administration of 150 mg every 12 hours for 7 days to healthy volunteers in a fed state, the mean (±SD) for apparent volume of distribution was 353 (122) L.
Following oral administration of 200 mg of lumacaftor every 24 hours to cystic fibrosis patients in a fed state for 28 days, the mean (+/-SD) for apparent volumes of distribution was 86.0 (69.8) L.
Elimination Route
Ivacaftor is well absorbed in the gastrointestinal tract. Following administration of ivacaftor with fat-containing foods, peak plasma concentrations were reached at 4 hours (Tmax) with a maximum concentration (Cmax) of 768 ng/mL and AUC of 10600 ng * hr/mL. It is recommended that ivacaftor is taken with fat-containing foods as they increase absorption by approximately 2.5- to 4-fold.
Following administration of Orkambi (lumacaftor/Ivacaftor) with fat containing foods, peak plasma concentrations were reached at 4 hours (Tmax). It's recommended that Orkambi should be taken with fat-containing foods as they increase absorption of lumacaftor by approximately 2-fold, and[DB08820 by 3-fold.
Half Life
In a clinical study, the apparent terminal half-life was approximately 12 hours following a single dose of ivacaftor. One source mentions the half-life ranges from 12 to 14 hours.
The half-life of lumacaftor is approximately 26 hours.
Clearance
The CL/F (SD) for the 150 mg dose was 17.3 (8.4) L/hr in healthy subjects.
The typical apparent clearance, CL/F (CV), of lumacaftor was estimated to be 2.38 L/hr.
Elimination Route
After oral administration, ivacaftor is mainly eliminated in the feces after metabolic conversion and this elimination represents 87.8% of the dose. From the total eliminated dose, the metabolites M1 and M6 account for the majority of the eliminated dose, being 22% for M1 and 43% for M6. Ivacaftor shows negligible urinary excretion as the unchanged drug.
Lumacaftor is primarily excreted unchanged in the feces (51%). A minimal amount of the parent compound and its metabolites are excreted in the urine.
Innovators Monograph
You find simplified version here Lumacaftor and ivacaftor
