Vertex’ three-drug cystic fibrosis regimen – combining the investigational next-generation corrector VX-445 with Kalydeco (ivacaftor) and tezacaftor – has achieved primary endpoints of two Phase III studies in patients the condition.

According to the results, the new combination resulted in statistically significant improvements in lung function (percent predicted forced expiratory volume in one second, or ppFEV1) in the two trials.

Data from a pre-specified interim analysis of the study involving people with one F508del mutation and one minimal function mutation showed a mean absolute improvement in ppFEV1 of 13.8 percentage points from baseline at week 4 of treatment compared to placebo.

In the trial in people with two F508del mutations, the addition of VX-445 in patients already receiving tezacaftor and ivacaftor resulted in a mean absolute improvement in ppFEV1 of 10.0 percentage points from baseline at week 4 of treatment compared to the control group in whom placebo was added to tezacaftor and ivacaftor.

Also, the triple combination regimen was generally well tolerated, and the safety and efficacy profile from the results support the potential submission of a New Drug Application (NDA) for the VX-445 triple combination regimen, Vertex noted.

The data follow Phase III results announced late last year for the triple combination of VX-659, tezacaftor and ivacaftor, which also showed a safety and efficacy profile supportive of a potential NDA submission.

“Given the similarity of the data for the 4-week primary efficacy endpoint for the VX-659 and VX-445 regimens and the near-term availability of the final 24-week data for both regimens in the second quarter of 2019,” Vertex said it plans to utilise these final 24-week data “to choose the best regimen to submit for regulatory approvals globally”.