New research suggests that tromethamine (also called THAM) — a drug already approved for the treatment of metabolic acidosis, where the body has too much acid — could be repurposed and used to treat airway disease in patients with cystic fibrosis.

The drug showed enhanced ability to kill bacteria in the airways of pigs and mucus samples from human patients with cystic fibrosis.

For their study, the researchers investigated the effect of tromethamine (which they refer to as Tham) on the acidity of airway surface liquid (ASL) and its ability to kill bacteria. They then showed that an aerosolized version of Tham was able to reduce acidity — that is raise pH — of the ASL in both pigs and humans with CF. Just as important, they found Tham boosted bacterial killing in the airways of pigs with CF and in sputum samples from human patients.

In the United States, Tham is currently approved – in injectable form – as a treatment for metabolic acidosis, a condition where the body either becomes too acidic or the kidneys are not able to remove enough acid from the body.