(CF), according to its manufacturer, Vertex Pharmaceuticals. Specifically, the drug is meant to treat the most common underlying cause of CF – having two copies of the F508del-CFTR mutation – and is the first drug to treat it.
The approval is based on a phase 3, two-part, open-label, multicenter study that assessed various doses in patents aged 2-5 years. The study demonstrated safety and tolerability in that age group equivalent to that seen in older patients. The drug is expected to be available for this age group within 2-4 weeks of this approval.
Available as oral granules in two doses for weight-based dosing (either lumacaftor 100 mg/ivacaftor 125 mg or lumacaftor 150 mg/ivacaftor 188 mg), the compound targets the defective chloride channels responsible for CF; the two halves work together to increase the number of chloride channels on cell surfaces and also improve their function.
Orkambi should be prescribed only for patients with CF who have the dual F508del-CFTR mutation; it is not indicated for other types of CF. Patients should not take this drug if they are taking drugs such as rifampin, phenytoin, triazolam, or cyclosporine because of possible drug interactions. It can also lead to worsening liver function and elevated blood liver enzymes, increased blood pressure, or cataracts. The most common side effects include breathing problems, nausea, fatigue, and rash. Full prescribing information is available on the FDA website.