Assessing the Tolerance and Clinical Benefit of feCAl tranSplantation in patientS With melanOma

PICASSO is a prospective, randomized, proof of concept clinical trial. This trial is about assessing the tolerance and clinical benefit of fecal microbiome transfer in patients with melanoma in addition to the usual treatment with immunotherapy combining ipilimumab (CTLA-4 inhibitor) and nivolumab (PD-1 inhibitor). In the proposed research, we will compare faecal transplantation using MaaT013 to placebo in 70 patients. Patients not exposed to anti CTLA-4 and anti PD1 or PDL-1 patients before the trial will be randomized to receive either: ipilimumab + nivolumab + MaaT013 (n = 35) or ipilimumab + nivolumab + placebo (n = 35). The estimated duration of the study is 37 months. Administration of MaaT013 or placebo will be performed every 3 weeks between baseline and week 9 then from week 15 to week 23 every 4 weeks. A total of 7 fecal microbiome transfer will be performed. Prior to the first administration (the day before) an evacuating enema by (MOVIPREP or equivalent) will be done, For subsequent administrations, an evacuating enema (equivalent to the specialty Normacol®) will be administered rectally before the transplantation of fecal microbiota or the placebo. Blood and stool samples will be collected as well as biopsies for the purposes of the study. An evaluation of the patient's condition will be made at week 27, Unblinding will be performed for patients who have progressed. Patients with disease progression who received placebo will be considered for receiving MaaT013, in an open-label basis, concurrently with nivolumab infusions, at week 31, 35, 39, 43 and 47. . The end-of-follow-up visit for all patients is scheduled for week 51. Patients who met the inclusion criteria, received Ipilimumab+Nivolumab, who consented to have a baseline stool microbiota analysis before starting treatment with ipilimumab + nivolumab. They will form a cohort of 50 patients.