By ANDREW JOSEPH @Drew Q Joseph

Vertex Pharmaceuticals on Monday won approval for its fourth treatment for cystic fibrosis, a combination drug that extends a new form of therapy to 90% of CF patients.

The drug will be marketed as Trikafta. The list price is $311,000 per year — the same as one of Vertex’s (VRTX) earlier CF treatments.

In a statement, acting Food and Drug Administration Commissioner Ned Sharpless said the approval makes “a novel treatment available to most cystic fibrosis patients, including adolescents, who previously had no options and giving others in the cystic fibrosis community access to an additional effective therapy.”

Cystic fibrosis is a progressive disease that damages the lungs and is caused by mutations in the CFTR gene. In patients with the disease, mucus clogs up the lungs and leads to frequent infections. Vertex’s drugs work by tweaking the faulty protein made by the gene to allow it to function properly.

The new drug is a triple combination regimen and was approved for patients 12 years and up with a type of genetic error called an F508del mutation. It is estimated to cover 90% of the 27,000 CF patients in the country, according to the FDA.

Earlier drugs from the Boston-based Vertex — the first CF drugs to target the underlying cause of the disease — worked on mutations held by smaller segments of CF patient population. The first, Kalydeco, was approved in 2012.

Vertex drugs already on the market have been transformational for some patients whose mutations the therapies target, though they have come under scrutiny for their prices. Health authorities in Europe have argued that the drugs do not offer adequate benefits to earn their costs.

In clinical trials, patients who received Trikafta experienced significant improvements in lung function.

The approval also helps Vertex achieve its goal of making available treatments that cover the large majority of CF-causing mutations. As Vertex’s CF work has crested, it has been diversifying its disease targets. It has turned to synthetic messenger RNA and the genome editor CRISPR as it works on future therapies, and it is acquiring Semma Therapeutics, which is developing on a stem cell-based diabetes treatment.

About the Author

Andrew Joseph

General Assignment Reporter

Andrew is a general assignment reporter. [email protected]@DrewQJoseph