By ADAM FEUERSTEIN @adamfeuerstein

NOVEMBER 27, 2018

Vertex Pharmaceuticals said Tuesday that treatment with a combination of three cystic fibrosis drugs resulted in a statistically significant improvement in lung function for patients enrolled in two pivotal clinical trials.

With these positive data, the Boston-based biotech takes a step closer towards its long-stated goal of marketing new therapies capable of treating 90 percent of the genetic mutations that cause cystic fibrosis.

A second pair of Phase 3 clinical trials testing a different triple combination will read out in the first quarter of next year, after which Vertex will choose the best option and submit a marketing application to regulators in the U.S. and Europe.

This triple combination regimen studied in Tuesday’s clinical trials starts with an experimental “corrector” drug called VX-659 designed to fix a protein that malfunctions in cystic fibrosis patients. Vertex deploys VX-659 on top of a two-drug backbone consisting of tezacaftor (another corrector) plus ivacaftor, which boosts the corrected protein and is already approved under the brand name Symdeko.

In the first Phase 3 study, Vertex’s VX-659 triple regimen showed a mean absolute improvement in lung function of 14 percentage points after four weeks of treatment, compared to a triple placebo. The result was statistically significant. The 385 patients enrolled in the trial had cystic fibrosis caused by a genetic mutation called F508del/Min, which renders them among the hardest to treat.

The second Phase 3 trial enrolled 111 patients with cystic fibrosis caused by two F508del mutations. Here, four weeks of treatment with VX-659 triple regimen resulted in a 10 percentage point improvement in lung function compared to a control group consisting of a placebo added to Symdeko.

Across both studies, the VX-659 combination regimen was well tolerated, Vertex said. Both studies are continuing to collect additional efficacy and safety data.

“These data mark a major milestone in our efforts to develop new cystic fibrosis medicines as they underscore the important clinical benefit that a triple combination regimen may provide to the vast majority of cystic fibrosis patients who have at least one F508del mutation,” Vertex Chief Medical Officer Reshma Kewalramani said in a statement.

Vertex shares were up 2 percent to $171 in early Tuesday trading. The somewhat muted stock reaction reflects baked-in investor expectations that these Phase 3 studies would be successful.

About the Author

Adam Feuerstein
Senior Writer, Biotech

Adam is STAT’s national biotech columnist, reporting on the intersection of biotech and Wall Street.

© 2018