Fecal microbiota transplants: A review of emerging clinical data on applications, efficacy, and risks (2015-2020)

Abstract

As the importance of the gut microbiota in health and disease is a subject of growing interest, fecal microbiota transplantation (FMT) was suggested as an attractive therapeutic strategy to restore homeostasis of the gut microbiota, thereby treating diseases that were associated with alteration of the gut microbiota. FMT involves the administration of fresh, frozen, or dried fecal microorganisms from the gut of a healthy donor into the intestinal tract of a patient. This rediscovery of the potential benefits of an ancient practice was accompanied by a rapid progression of our understanding of the roles and mechanisms of gut microbes in the pathogenesis of disease. With a growing number of diseases being associated with dysbiosis or the alteration of gut microbiota, FMT was suggested as an attractive therapeutic strategy to "reset the gut" and initiate clinical resolutions or remissions. The number of FMT clinical trials is increasing worldwide, but no trials are registered in the Gulf region; this suggested the need for raising awareness of the latest studies on FMT. This review presented the emergent preclinical and clinical data to give an overview of the potential clinical applications, the benefits, and inconveniences that were worth considering for eventual future testing of fecal transplants in Qatar and the Middle East. This study highlighted the diversity of methods tested and commented on the variables that can affect the assessment of the effectiveness of FMT in specific diseases. The risks associated with FMT and the threat of antimicrobial resistance for this therapeutic approach were reviewed. From gastrointestinal diseases to neurodevelopmental disorders, understanding the roles of the gut microbiota in health and disease should be at the heart of developing novel, standardized, yet personalized, methods for this ancient therapeutic approach.

Keywords: Clostridium difficile; Fecal transplant; Qatar; antibiotic resistance; clinical trial; microbiota.

Figure 1.

Growing scientific interest toward fecal transplants over the past 15 years. A search using the MeSH term “fecal transplant” was done on PubMed and filtered for the last 15 years.

Figure 2.

Key milestones in the history of fecal transplants.

Figure 3.

Worldwide distribution of fecal transplants clinical trials as of May 19, 2020. A total of 215 trials registered in database clinicaltrials.gov with search term “fecal transplant.” Trials that were labeled as withdrawn, terminated, or suspended were excluded.

Figure 4.

Worldfecal transplants clinical trials (number per disease category). Abbreviations: IBD = inflammatory bowel disease; AMR = antibiotic resistance; GVDH = graft versus host disease; C. diff = Clostridium difficile infection; Neuro/psych = neurological diseases and neuropsychiatric disorders; IBS = irritable bowel syndrome. Data were obtained from clinicaltrials.gov as per method detailed in section 2.

Figure 5.

Proportions of clinical trials for GI diseases and disorders. Abbreviations: UC = ulcerative colitis; IBD = inflammatory bowel disease (nonspecified); CD = Crohn's disease; Other GI = other gastrointestinal disorders; Liver = liver diseases; IBS = irritable bowel syndrome. Data were obtained from clinicaltrials.gov as per method detailed in section 2.