The Efficacy of Fecal Microbiota Transplatation on Axial Spondyloarthritis Patients Resistant to Conventional Treatment

Current pharmacological management of inflammatory rheumatism and in particular axial SpA remains imperfect. Only 50% of patients respond to the most effective biotherapies, and many of them are only partially relieved. In addition, these are extremely expensive treatments that expose them to the risk of potentially serious side effects. Compelling evidence indicates that gut dybiosis could be a critical trigger of inflammation in axial SpA and thus correcting dysbiosis represents an attractive way of reversing the pathogenic process.The efficacy of FMT in patients with axial SpA has never been studied. This randomized double-blind study will be the first to assess feasability of FMT in axial SpA, the capacity of this procedure to restore healthy microbiome, its tolerance and its potential efficacy on disease activity. If sucessfull, this trial would set the path to larger-scale clinical trials of FMT to treat axial SpA. Two-co primary objectives in a hierarchical design: * to evaluate the capacity of FMT to correct dysbiosis in active axial SpA despite well-conducted phamacological treatment by replacing pre-existing dysbiotic microbiota with healthier microbiota. * to explore the efficacy of FMT versus placebo on clinical evolution of SpA.