Fecal Transplants May Address Gastrointestinal Side Effects of Immune Checkpoint Inhibitor Therapy

Fecal microbiome transplants (FMTs) may alleviate gastrointestinal side effects that can accompany immune checkpoint inhibitor (ICI) therapy, a small study has found. While ICIs have improved outcomes in cancer patients, they can also lead to gut toxicities like immune-mediated colitis, which can be treated either by stopping ICI therapy or with immunosuppressants. In Science Translational Medicine, though, an MD Anderson Cancer Center-led team has examined another approach: treating 12 cancer patients with immune-mediated colitis who had not responded to corticosteroids with an FMT from healthy individuals. The gut microbiome, the researchers note, has been linked to ICI response. Following transplant, 10 of the 12 patients had improved gut symptoms and seven had complete responses. A comparison of gut microbiome samples at baseline versus after FMT revealed an increase in Collinsella, Bifidobacterium, and other bacteria as well as changes in the immune cells present. "We expect that FMT will become a useful approach to treat patients with [immune mediated colitis] at earlier stages of presentation, as an addition or alternative to standard treatments," the researchers write in their paper.