Faecal microbiota transplantation: from practice to legislation before considering industrialization.

Recurrent Clostridium difficile infections constitute an important medical concern. Evidence has been provided showing that faecal microbiota transplantation is a more efficient treatment than antibiotics. Serious side effects are unusual, and acceptability is not an obstacle. Nevertheless, protocols are heterogeneous with respect to the selection of donors and the methodology used for the faecal transplantation. Regulations by both the Food and Drug Administration and the French authorities consider stool samples to be drugs, and suggest strict supervision in clinical trials. Donor screening by questionnaire or by blood and stool analysis, which is essential in eliminating pathogens or viruses before transplantation, is similar in different countries, with a few exceptions. The traceability of the faecal transplant and long-term follow-up of the patients in clinical trials are issues that may be difficult to organize. The use of frozen microbiota facilitates transplantation, and the nasogastric route seems to be at least as effective as other invasive methods and avoids the risk of anaesthesia. Synthetic microbiota is an approach that selects a mixture of bacteria, thereby eliminating the risk of transmissible disease; however, this approach is not yet evidence-based. The use of pills, which is currently being tested in clinical trials, will certainly be the starting point for the extensive use and wide industrialization of faecal microbiota transplantation.