The great fecal microbiota transplant debate

An article was published today in the Atlantic that does a really nice job of describing the controversy surrounding fecal microbiota transplants (FMTs).  Basically, FMTs have been highly effective (>90% effective) in treating C. Difficile infections, and this efficacy has been even used as proof of the causal role of dysbiosis in C. Diff infection.  

The problem though, is that FMTs are currently unregulated, and the real question is how does the FDA regulate this new treatment, especially with how little is known about the microbiome.  The first question the FDA has to answer is whether or not fecal microbiota is a drug or a tissue.  Currently it is considered a drug but many common definitions would call it a tissue.

In addition, no one knows any long term consequences with FMTs, or what diseases to look for in donors, or how to screen FMTs at all.  Fecal microbiota is obtained just as you would imagine, through stool samples, and everything in that stool is transferred, the entire microbiota, including viruses.  It is a really complex issue that comes down to ethics, the responsibility of government, and the science of the microbiome.  Without guidance though, many have resorted to DIY FMTs which is not a good idea!

At the AMI we are aligned with the editorial written by a consortium of microbiome scientists, including our very own Marty Blaser and Rob Knight.  They support the FDA's cautious approach and note that past transplant procedures, like with blood, have resulted in unexpected disease transfer.  They also do see the benefit of FMTs and want to move forward with research to develop proper protocols, registries, and databases, as well as thorough clinical trials.  

A fellow non-profit here in Cambridge, Open Biome, based out of Eric Alm's lab at MIT, has created the first stool bank.  Organizations such as this will be essential to centralizing data and clinical outcomes, and we support their efforts.

Finally, drugs are being developed for C. Diff infection that are working.  Seres Health is a start-up in Cambridge, that has had great success in an oral treatment to C. Diff.  This may very well be the treatment for C. Diff in the future, but with so many diseases being linked to the microbiome, FMTs will again be at the forefront of therapeutics, even if they have not been successful for more complex diseases such as IBS and ulcerative colitis.

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The views expressed in the blog are solely those of the author of the blog and not necessarily the American Microbiome Institute or any of our scientists, sponsors, donors, or affiliates.