Vertex cystic fibrosis triple combo therapy succeeds in important trials

(Reuters) – Vertex Pharmaceuticals Inc on Wednesday said its triple-combination treatment for cystic fibrosis led to significant lung function improvement in two late-stage studies, paving the way for a therapy that could eventually address 90 percent of people with the life-shortening genetic condition.

The trials tested the experimental drug VX-445 in combination with Vertex’s backbone double-drug combination. Its current products can benefit roughly 50 percent of CF patients, and the highly-anticipated positive data would represent a major expansion of the treatable population.

The company had previously tested another experimental drug, VX-659, with the two-drug combination approved under the brand name Symdeko.

“This triple data is, if anything, even better than the previously released VX-659 triple results, and in our view effectively guarantees the launch, approval … and adoption of one of these combinations with resulting multi-billion dollar sales to Vertex,” Leerink analyst Geoffrey Porges said.

However, Vertex shares fell 2 percent as the company said it would delay filing for U.S. approval while it further studies data to select which drug to add to its double combination.

Cystic fibrosis, which affects about 75,000 people in North America, Europe and Australia, is caused by a defective or missing protein and results in serious lung infections, declining lung function and often early death.

Vertex was the first company to bring to market drugs that address the underlying cause of the disease rather than just symptoms.

In a trial that tested patients with two different specific gene mutations, considered the most difficult to treat CF population, there was a 13.8 percentage point improvement in lung function compared to a placebo.

The followed triple combination data released in November involving VX-659 that showed a 14 percent lung function improvement in these patients.

“With the data looking similar between the two regimens to date, we think it is a prudent move by the company to wait for more data … given they will have a better picture,” Jefferies analyst Michael Yee said.

Vertex, which had earlier expected to file for U.S. approval by mid-year, said it now planned to apply for triple combination approval by the third quarter.

A second triple combination trial with VX-445 in patients with two of the same genetic mutations led to a 10 percentage point improvement in lung function.

The backbone drugs in the triple combinations are ivacaftor and tezacaftor, which make up Symdeko. Ivacaftor is also sold as a standalone treatment, Kalydeco, and is part of another double combination product called Orkambi.