A new drug application for a triple combination regimen of elexacaftor plus tezacaftor/ivacaftor to treat cystic fibrosis has been submitted to the FDA, with a request for priority review, according to a manufacturer press release.

Vertex, the manufacturer of elexacaftor (VX-445) and tezacaftor/ivacaftor (Symdeko), based the submission on the positive results of two global phase 3 studies, including a 24-week study in people with one F508del mutation and one minimal function mutation and a 4-week study in people with two F508del mutations.

In both studies, the triple combination therapy was associated with statistically significant improvements in the primary endpoint of lung function, as defined by percent predicted FEV1, and key secondary endpoints. The triple combination therapy was also well tolerated, according to the release.

The triple combination regimen of elexacaftor plus tezacaftor/ivacaftor was granted breakthrough therapy designation in May 2018 in the United States.