Frontiers in Microbiology Publishes Article Detailing Novel Microbiome-based Biomarker of Post-Antibiotic Disruptions in Gut Microbiota

Ferring’s Microbiome Health Index™ is a promising tool that measures disrupted gut microbiota after antibiotic treatment, subsequent gut microbiota restoration, and the potential clinical impact of microbiome-based live biotherapeutics

PARSIPPANY, N.J.--(BUSINESS WIRE)-- Ferring Pharmaceuticals and Rebiotix, a Ferring Company, today announced a publication detailing the development and validation of their first-of-its-kind prototype biomarker, designed to distinguish post-antibiotic disruptions to the human gut microbiota, known as dysbiosis, from healthy gut microbiota. The Microbiome Health Index for post-Antibiotic dysbiosis (MHI-A), published in Frontiers in Microbiology, was developed to better understand and manage the risks of antibiotic administration and help guide the development of live biotherapeutic products – a potential new class of drugs.1

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The gut microbiome is a highly-diverse microbial community that plays an essential role in human health. Antibiotics are known to disrupt the composition and/or diversity of the gut microbiome.2,3,4 This disruption is a risk factor for serious illnesses, including C. difficile infection (CDI) and potential recurrences. While the impact of antibiotic use on dysbiosis is documented, measurements of dysbiosis are complex and often vary between studies, leaving a need for a simple biomarker identifying gut microbiota composition that can help support diagnostic decisions.1

The Ferring MHI-A algorithm was designed to differentiate post-antibiotic dysbiosis from healthy microbiota by relating the relative abundances of bacteria naturally found in the gut microbiome that are associated with health (Bacteroidia and Clostridia) versus those that could be considered harmful (Gammaproteobacteria and Bacilli).1 The study shows MHI-A has high accuracy to distinguish post-antibiotic dysbiosis from healthy microbiota. MHI-A values were consistent across multiple healthy populations and were significantly shifted by antibiotic treatments known to alter microbiota compositions and shifted less by microbiota-sparing antibiotics. The study concludes that MHI-A is a promising biomarker of post-antibiotic dysbiosis and subsequent restoration. MHI-A may also be useful for rank-ordering the microbiota-disrupting effects of antibiotics and as a pharmacodynamic measure of microbiota restoration.1

“This biomarker provides a concise metric for assessing the complex changes in the microbiome of trial participants pre- to post-treatment, expanding our understanding of microbiome restoration after antibiotic use,” said lead author Ken Blount, Chief Scientific Officer, Rebiotix, Vice President Microbiome Research, Ferring Pharmaceuticals. “This is a crucial step in unlocking the potential of microbiome-based live biotherapeutics, further demonstrating Ferring’s leadership in advanced research that addresses the urgent needs of patients with recurrent C. diff.”

About the Study

MHI-A was developed using longitudinal data from more than 200 treated patients across three controlled clinical trials of RBX2660 and RBX7455, Ferring’s two leading investigational microbiome-based live biotherapeutic products for the reduction of recurrent CDI. It was validated using published data describing the microbiome of several healthy and antibiotic-treated populations.1

Comparing the algorithm findings against baseline samples representative of post-antibiotic dysbiosis, the study authors concluded that MHI-A values were consistent across multiple healthy populations. The population microbiomes were significantly shifted by antibiotic treatments known to alter microbiota compositions, while they were shifted less by microbiota-sparing antibiotics. Study authors also observed that clinical response to RBX2660 and RBX7455 correlated with a shift of MHI-A from dysbiotic values to healthy representations.1

Based on the data sets, the study authors suggest MHI-A may rank-order specific antibiotics’ impact on the microbiota, which could be valuable for treatment decisions and the development of more microbiota-sparing antibiotics. Additionally, they concluded MHI-A might be useful for identifying patients at risk of dysbiosis-related complications.1

About C. difficile infection
C. difficile infection (CDI) is a serious and potentially deadly disease that impacts people across the globe. The C. difficile bacterium causes debilitating symptoms such as severe diarrhea, fever, stomach tenderness or pain, loss of appetite, nausea and colitis (an inflammation of the colon).5 Declared a public health threat by the U.S. Centers for Disease Control and Prevention (CDC) requiring urgent and immediate action, CDI causes an estimated half a million illnesses and tens of thousands of deaths in the U.S. alone each year.5,6,7

C. difficile infection often is the start of a vicious cycle of recurrence, causing a significant burden for patients and the healthcare system.8,9 Up to 35% of CDI cases recur after initial diagnosis2,3 and people who have had a recurrence are at significantly higher risk of further infections.10,11,12,13 After the first recurrence, it has been estimated that up to 60% of patients may develop a subsequent recurrence.14 Restoring the gut microbiome is increasingly accepted as a promising treatment option for recurrent C. difficile infection.15

About RBX2660
RBX2660 is a potential first-in-class microbiota-based live biotherapeutic being studied to deliver a broad consortium of diverse microbes to the gut to reduce recurrent C. difficile infection. RBX2660 has been granted Fast Track, Orphan, and Breakthrough Therapy designations from the U.S. Food and Drug Administration (FDA). The pivotal Phase 3 program builds on nearly a decade of research with robust clinical and microbiome data collected over six controlled clinical trials with more than 1,000 participants.

About Ferring Pharmaceuticals
Ferring Pharmaceuticals is a research-driven, specialty biopharmaceutical group committed to helping people around the world build families and live better lives. Headquartered in Saint-Prex, Switzerland, Ferring is a leader in reproductive medicine and maternal health, and in specialty areas within gastroenterology and urology. Ferring has been developing treatments for mothers and babies for over 50 years and has a portfolio covering treatments from conception to birth. Founded in 1950, privately-owned Ferring now employs approximately 6,500 people worldwide, has its own operating subsidiaries in nearly 60 countries and markets its products in 110 countries. Learn more at, or connect with us on Twitter, Facebook, Instagram, LinkedIn and YouTube.

Ferring is committed to exploring the crucial link between the microbiome and human health, beginning with the threat of recurrent C. difficile infection. With the 2018 acquisition of Rebiotix and several other alliances, Ferring is a world leader in microbiome research, developing novel microbiome-based therapeutics to address significant unmet needs and help people live better lives. Connect with us on our dedicated microbiome therapeutics development channels on Twitter and LinkedIn.

About Rebiotix
Rebiotix Inc, a Ferring Company, is a late-stage clinical microbiome company focused on harnessing the power of the human microbiome to revolutionize the treatment of challenging diseases.Rebiotix has a diverse pipeline of investigational drug products built on its pioneering microbiota-based MRTTM drug platform. The platform consists of investigational drug technologies designed to potentially rehabilitate the human microbiome by delivering a broad consortium of live microbes into a patient’s intestinal tract. For more information on Rebiotix and its pipeline of human microbiome-directed therapies for diverse disease states, visit, or connect with us on Twitter, Facebook, LinkedIn and YouTube.


  1. Blount K, Jones, C. Walsh, D et al. Development and Validation of a Novel Microbiome-Based Biomarker of Post-Antibiotic Dysbiosis and Subsequent Restoration. Frontiers in Microbiology.
  2. Lessa FC, Mu Y, Bamberg WM, et al. Burden of Clostridium difficile infection in the United States. N Engl J Med. 2015;372(9):825-834.
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  12. Kelly, CP. Can we identify patients at high risk of recurrent Clostridium difficile infection? Clin Microbiol Infect. 2012; 18 (Suppl. 6): 21–27.
  13. Smits WK, et al. Clostridium difficile infection. Nat Rev Dis Primers. 2016;2:16020. doi: 10.1038/nrdp.2016.20.
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  15. van Nood E, Vrieze A, Nieuwdorp M, et al. Duodenal infusion of donor feces for recurrent Clostridium difficile. N Engl J Med. 2013;368(5):407-415.



Lisa Ellen
Director, Brand Communications
P: +1-862-286-5696


Source: Ferring Pharmaceuticals

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