FRIDAY, Nov. 1, 2019 (HealthDay News) -- For patients with cystic fibrosis with Phe508del-minimal function genotypes, elexacaftor-tezacaftor-ivacaftor, which was recently approved by the U.S. Food and Drug Administration, is efficacious, according to a study published online Oct. 31 in the New England Journal of Medicine to coincide with the annual North American Cystic Fibrosis Conference, held from Oct. 31 to Nov. 2 in Nashville, Tennessee.
Peter G. Middleton, M.D., from the University of Sydney, and colleagues randomly assigned 403 patients aged 12 years or older with cystic fibrosis with Phe508del-minimal function genotypes to receive either elexacaftor-tezacaftor-ivacaftor or placebo for 24 weeks.
The researchers found that compared with placebo, elexacaftor-tezacaftor-ivacaftor resulted in a percentage of predicted forced expiratory volume in one second (FEV1) that was 13.8 points higher at four weeks and 14.3 points higher through 24 weeks. In addition, the rate of pulmonary exacerbations was 63 percent lower, the respiratory domain score on the Cystic Fibrosis Questionnaire-Revised was 20.2 points higher, and the sweat chloride concentration was 41.8 mmol/L lower. Elexacaftor-tezacaftor-ivacaftor had an acceptable side-effect profile and was generally safe. In the elexacaftor-tezacaftor-ivacaftor group, 1 percent of patients had adverse events leading to discontinuation of the trial regimen.
"These results provide evidence that elexacaftor-tezacaftor-ivacaftor can modulate a single Phe508del allele in people with cystic fibrosis, thus addressing the underlying cause of disease in the large majority of patients," the authors write.
The study was partially funded by Vertex Pharmaceuticals, the manufacturer of elexacaftor-tezacaftor-ivacaftor.