Adults with kidney cancer who received faecal microbiota transplants on top of their existing drugs did better than those who had placebo transplants as their add-on interventionBacteria in stools could be an unexpected weapon in the fight against cancer LEWIS HOUGHTON/SCIENCE PHOTO LIBRARYFor people not responding to a type of cancer treatment, a faecal transplant from someone who had success with the drug could boost their odds. AdvertisementWhen treating cancer, immunotherapy drugs known as checkpoint inhibitors can be effective by helping the immune system destroy cancer cells, but they don’t work for everyone. But such studies typically focused on melanoma, a type of skin cancer, and didn’t compare the effects of faecal transplants to a placebo. Within the FMT group, the participants’ cancer was stable for two years, on average, after their first transplant, compared with nine months in the placebo group. The faecal transplants also seemed to alter levels of bacteria already present in the recipients’ guts.