Cystic fibrosis affects about 30,000 people in the U.S. with a life expectancy of 44 years for patients born today. The team behind Trikafta have created a small-molecule drug that can tweak the faulty protein. This allows it to function more normally and can drastically improve patient symptoms. The drug’s mechanism of action means it treats the underlying genetic cause of the disease in 90% of the CF population. Cystic fibrosis is caused by mutations in the CFTR gene that lead to a defective protein being produced. The protein doesn’t allow chloride to flow in and out of cells normally and prevents water from hydrating the cellular surface, leading to a buildup of thick mucus and difficulty breathing. “No one thought that using small molecules would be enough to correct the underlying function of a giant protein,” says Vertex, the company behind Trikafta, CEO Jeffrey Leiden to FastCompany.