An experimental three-day therapy that involves introducing Firmicutes spores into the gut may reduce the risk of Clostridium difficile reinfection by nearly 70%, a phase III trial shows.

The treatment, known as SER-109, appeared to be more effective in patients under 65, which the US researchers say is “clinically important” given their increased risk of recurrent disease and hospital readmission.

“The results are incredibly exciting,” said first author and gastroenterologist Dr Paul Feuerstadt, from the Yale School of Medicine in New Haven, Connecticut.

“The patients that go through recurrent and multiple-recurrent C. difficile infections live with PTSD worrying that this is going to come back; to have a treatment like this that can really shut this down is huge.”