A UK-led clinical trial has found that a microbiome-based therapy called MB097 — a daily capsule containing nine bacterial strains — may help advanced melanoma patients overcome resistance to immunotherapy. The MELODY-1 Phase 1b trial enrolled 41 patients across four countries who had stopped responding to KEYTRUDA, a leading immune checkpoint inhibitor. Researchers found MB097 was safe, well-tolerated, and successfully established itself in patients' gut microbiomes. Early signs suggest it may reactivate immune responses against tumors. This trial marks a meaningful step in moving microbiome medicine from wellness culture into real clinical oncology, reinforcing the idea that gut bacteria play a direct role in how the immune system fights disease and ages.
