The FDA has approved Vertex Pharmaceuticals' next-generation treatment for a rare and progressive genetic disease, the company said, expanding its dominance in the market for cystic fibrosis.

The drugmaker, with almost $10 billion in sales last year, has significantly impacted cystic fibrosis treatment, turning it from a disease with a median death age of around 30 years to a manageable condition through its drugs — such as its top-selling Trikafta.

The once-daily triple combination therapy, branded Alyftrek, was approved to treat patients aged 6 years and older who have at least one F508del mutation or another mutation in the CFTR gene, which is responsive to the therapy.

The approval also helps shield from erosion of sales when Trikafta loses its patent, said William Blair analyst Myles Minter ahead of the decision.

There are about 40,000 people with cystic fibrosis in the U.S., according to the American Lung Association.

The company has established a wholesale acquisition cost of $370,269 on an annual basis for the therapy, which would be available in January.

Alyftrek is a combination of Vertex's vanzacaftor, tezacaftor and deutivacaftor.

In late-stage trials, treatment with the triple combination was non-inferior to treatment with Vertex's Trikafta, which is taken twice daily.

The company aims to launch five new treatments by 2028, including the next-generation CF drug and a non-opioid pain management drug.

The U.S. health regulator is set to decide on the treatment for acute pain by the end of January.