MaaT033 impact on patients’ gut microbiota richness, engraftment, and Butycore levels relies on baseline microbiota (n = 21). For each patient’s cohort, for MaaT033, and at each visit (D1, D7, D19, and D44): (A) Richness index at species level. (B) Shannon index at species level. (C) Relative abundance of Butycore, a group of 15 SCFA (mainly butyrate)-producing bacterial genera (Blautia, Faecalibacterium, Alistipes, Eubacterium, Bifidobacterium, Ruminococcus, Clostridium, Coprococcus, Odoribacter, Roseburia, Anaerostipes, Oscillibacter, Subdoligranulum, Butyrivibrio, and Holdemanella). (D) Engraftment at species level. The definition of engraftment is linked with the detection of donor-specific bacterial species that were not present in the patient’s feces before MaaT033 administration. For panels A to D, medians with interquartile ranges are provided. (E) Engraftment of MaaT033 at each visit by richness measured at D1 (at species level). Statistical significance was performed using Pearson correlation test.