Vertex Pharmaceuticals announced that the U.S. Food and Drug Administration (FDA) has approved the expanded use of TRIKAFTA (elexacaftor/tezacaftor/ivacaftor and ivacaftor) for the treatment of people with cystic fibrosis (CF) ages 2 and older who have at least one F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene or a mutation that is responsive to TRIKAFTA based on clinical and/or in vitro data. The approval significantly broadens the number of individuals eligible for this CFTR modulator therapy. In addition, safety information on liver injury and liver failure has been updated from warnings and precautions to a boxed warning.
Expansion of Treatable Mutations
With this approval, 94 additional non-F508del CFTR mutations have been added to the TRIKAFTA label. This expansion means that approximately 300 more people with CF in the U.S. are now eligible for a medicine to treat the underlying cause of their disease for the first time.
Impact of TRIKAFTA
"Since its first approval in 2019, TRIKAFTA has had a transformative impact on tens of thousands of people living with cystic fibrosis," said Carmen Bozic, M.D., Executive Vice President, Global Medicines Development and Medical Affairs, and Chief Medical Officer, Vertex. "With this approval, even more patients may be able to benefit from a medicine that treats the underlying cause of their disease, and we look forward to continuing the work to extend the approvals and availability of our medicines to patients around the world."
About Cystic Fibrosis
Cystic fibrosis (CF) is a rare, life-shortening genetic disease affecting more than 92,000 people globally. CF is a progressive, multi-organ disease that affects the lungs, liver, pancreas, GI tract, sinuses, sweat glands and reproductive tract. CF is caused by a defective and/or missing CFTR protein resulting from certain mutations in the CFTR gene. Children must inherit two defective CFTR genes — one from each parent — to have CF, and these mutations can be identified by a genetic test. While there are many different types of CFTR mutations that can cause the disease, the vast majority of people with CF have at least one F508del mutation. CFTR mutations lead to CF by causing CFTR protein to be defective or by leading to a shortage or absence of CFTR protein at the cell surface. The defective function and/or absence of CFTR protein results in poor flow of salt and water into and out of the cells in a number of organs. In the lungs, this leads to the buildup of abnormally thick, sticky mucus, chronic lung infections and progressive lung damage that eventually leads to death for many patients. The median age of death is in the 30s, but with treatment, projected survival is improving.
How TRIKAFTA Works
In people with certain types of mutations in the CFTR gene, the CFTR protein is not processed or folded normally within the cell, and this can prevent the CFTR protein from reaching the cell surface and functioning properly. TRIKAFTA (elexacaftor/tezacaftor/ivacaftor and ivacaftor) is an oral medicine designed to increase the quantity and function of the CFTR protein at the cell surface. Elexacaftor and tezacaftor work together to increase the amount of mature protein at the cell surface. Ivacaftor, which is known as a CFTR potentiator, is designed to facilitate the ability of CFTR proteins to transport salt and water across the cell membrane. The combined actions of elexacaftor, tezacaftor and ivacaftor help hydrate and clear mucus from the airways.
Important Safety Information
The updated safety information includes a boxed warning regarding drug-induced liver injury and liver failure. Cases of liver failure leading to transplantation and death have been reported in patients with and without a history of liver disease taking TRIKAFTA, in both clinical trials and the post-marketing setting. Liver injury has been reported within the first month of therapy and up to 15 months following initiation of TRIKAFTA.
Assess liver function tests (ALT, AST, alkaline phosphatase, and bilirubin) in all patients prior to initiating TRIKAFTA, then every month during the first 6 months of treatment, every 3 months for the next 12 months, and at least annually thereafter. Consider more frequent monitoring for patients with a history of liver disease or liver function test (LFT) elevations at baseline.
TRIKAFTA should not be used in patients with severe hepatic impairment (Child-Pugh Class C). TRIKAFTA is not recommended in patients with moderate hepatic impairment (Child-Pugh Class B). If used, use with caution at a reduced dosage and monitor patients closely.
Hypersensitivity reactions, including cases of angioedema and anaphylaxis, have been reported in the post-marketing setting. If signs or symptoms of serious hypersensitivity reactions develop during treatment, discontinue TRIKAFTA and institute appropriate therapy. Concomitant use with strong CYP3A inducers is not recommended, while the dose of TRIKAFTA should be reduced when used concomitantly with moderate or strong CYP3A inhibitors.
Non-congenital lens opacities have been reported in pediatric patients treated with ivacaftor-containing regimens. Baseline and follow-up ophthalmological examinations are recommended in pediatric patients initiating treatment with TRIKAFTA.
