Vertex Pharmaceuticals Incorporated provided an update on its ongoing Phase 3 development program of its investigational compound VX-661 in combination with ivacaftor, which includes four studies that together are expected to enroll more than 1,000 people with cystic fibrosis (CF). Based on a planned interim futility analysis conducted by the study's independent Data Safety Monitoring Board (DSMB), Vertex plans to stop the study of VX-661 and ivacaftor in people with one copy of the F508del mutation and one copy of a mutation that results in minimal CFTR protein function (F508del het/min).
There were no safety concerns noted in the DSMB's review of the data. Vertex also announced that enrollment is now complete in the study of VX-661 and ivacaftor in people with two copies of the F508del mutation (F508del homozygous) and that the company expects to complete enrollment in the study of people with one copy of the F508del mutation and one copy of a residual function mutation in September.
"While we recognize that people with CF with minimal function mutations have a form of the disease that is particularly difficult to treat, we believed it was important to evaluate whether a dual combination of VX-661 and ivacaftor could provide some benefit to these patients given they do not today have a medicine to treat the cause of their disease," said Jeffrey Chodakewitz, M.D., Executive Vice President and Chief Medical Officer at Vertex.
"These results suggest that a triple combination regimen may provide this group of people with CF the best chance at obtaining a meaningful benefit and we look forward to beginning the first study of a next-generation corrector together with VX-661 and ivacaftor in this group of patients later this year, pending data from our ongoing Phase 1 studies in healthy volunteers."
Vertex plans to submit a New Drug Application (NDA) to the FDA for VX-661 in combination with ivacaftor in the second half of 2017, pending data from the Phase 3 program. The NDA is expected to include data from the study in people with minimal function mutations.
