The medication also does not appear to change a persons quality of life or the number of times a year a person has a worsening of lung function. Effects on life expectancy are unclear. Side effects
Some people taking the combination drug had elevated transaminases; the combination drug should be used with caution for people with advanced liver disease and liver function should be measured for the first three months for all people starting the combination drug.People starting the combination have respiratory discomfort, and some children taking the combination drug developed cataracts.Lumacaftor/ivacaftor may interfere with hormonal contraceptives. Dosage of the combination drug should be reduced if the person is taking a drug that inhibits CYP3A, and inducers of CYP3A should not be used concomitantly. Mechanism of action
F508del is a mutation that causes the CFTR protein to misfold and cells destroy such proteins soon after they are made; lumacaftor acts as a chaperone during protein folding and increases the number of CFTR proteins that are trafficked to the cell surface. Ivacaftor is a potentiator of CFTR that is already at the cell surface, increasing the probability that the defective channel will be open and allow chloride ions to pass through the channel pore. The two drugs have synergistic effects. Physical properties
Each of lumacaftor and ivacaftor is a white to off-white powder that is practically insoluble in water. The combination drug is a single pill containing 200 mg of lumacaftor and 125 mg of ivacaftor.
This followed discussions where Vertex had wanted £105 000 per patient for Orkambi.The drug was not patented in Argentina, so can be made by other companies. Buyers clubs in the UK have been buying the generic version from the Argentinian company Gador. References
External links
"Ivacaftor mixture with lumacaftor". Drug Information Portal. U.S. National Library of Medicine.