Faecal transplants can treat some cancers — but probably won’t ever be widely used
Source: Nature, July 2024
In February 2021, a pair of remarkable clinical trials was published1,2. Each one involved people with melanoma. Some participants had been successfully treated using drugs called immune checkpoint inhibitors, which help the body to destroy cancer cells. The others had failed to respond to the treatment.
In both studies, researchers collected stool samples from the people who had benefited from the immunotherapy. They then implanted these samples — and the gut bacteria that they contained — into the people who had not responded to the drugs, and administered the checkpoint inhibitors again. The hope was that this faecal microbiota transplant (FMT) would transfer the ability to respond to this potentially life-saving treatment.
Experiments in mice had already suggested that differences in the composition of people’s intestinal microbiomes might account for much of the notorious variability in responses to checkpoint inhibitors3. Mice implanted with gut microbes from people who had responded positively to immunotherapy tended to respond well, too. But when transplants came from non-responders, the drugs were ineffectual.