Retrospective Analysis of Data Evaluating Safety and Efficacy of REBYOTA™ (fecal microbiota, live – jslm) in a Real-World Patient Population with Comorbidities and Risk Factors Published in Open Forum Infectious Diseases

  • REBYOTA is indicated for the prevention of recurrence of Clostridioides difficile (C. diff) infection in individuals 18 years of age and older, following antibiotic treatment for recurrent C. diff infection
  • Analysis is the first to evaluate safety and efficacy of REBYOTA in a real-world population with comorbidities and risk factors with up to six months of follow up

PARSIPPANY, N.J.--()--Ferring Pharmaceuticals today announced that Open Forum Infectious Diseases has published a retrospective analysis of data evaluating the safety and efficacy of REBYOTA™ (fecal microbiota, live – jslm) for the prevention of recurrent Clostridioides difficile (C. diff) infection in a range of adult patients representative of those seen in clinical practice – including patients with irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).

In the analysis, patients with recurrent C. diff infection (rCDI) and treated with REBYOTA under the Assured Active Treatment (AAT) program were retrospectively identified across five clinical trial sites. The AAT program offered REBYOTA to adults not eligible for clinical trial participation or who needed additional treatment following study participation. The primary objective was to evaluate the safety and tolerability of REBYOTA through six months after treatment. The secondary objectives were to evaluate efficacy in preventing rCDI within eight weeks of treatment and sustained response for six months after treatment. The primary safety set (PSS), which served as the analysis set for the safety and efficacy endpoints, included 64 patients who were REBYOTA treatment naive and had comprehensive medical records for six months following treatment.

In the PSS, most treatment-emergent adverse events (TEAEs) were mild to moderate in severity and comparable between patients with comorbid conditions and the overall patient population. The most common TEAEs occurring in five percent or more of patients in the PSS were GI disorders at 45.3%, including abdominal pain (14.1%), diarrhea (14.1%), bloating (6.3%), gas (6.3%) and nausea (6.3%), and infections at 25%, including urinary tract infection (10.9%) and C. diff infection (7.8%).1 Serious TEAEs were experienced by 12.5% of patients. There were no serious adverse events related to REBYOTA or the administration procedure. Four patients in the PSS received REBYOTA via colonoscopy. In the PSS, 82.8% of REBYOTA-treated patients responded at eight weeks, and 88.7% of those patients maintained a sustained response through six months.

“People who experience recurrent C. diff infection often have chronic gastrointestinal conditions that can also cause uncomfortable and painful symptoms, making their infection-related symptoms even more difficult to manage,” said Paul Feuerstadt, M.D., F.A.C.G., A.G.A.F., Yale University School of Medicine and lead author. “This is the first analysis evaluating safety and efficacy of REBYOTA in patients who are often seen in clinical practice struggling with other gastrointestinal illnesses in addition to C. diff infection, who may be able to prevent recurrence of C. diff infection with a microbiome-based treatment following antibiotics.”

In the PSS, 70.3% of patients had gastrointestinal and nonspecific inflammation and dysfunctional conditions, and 65.6% had immune-mediated/autoimmune disorders at baseline. Comorbid conditions included irritable bowel syndrome (21.9%), microscopic colitis (10.9%), Crohn’s disease (7.8%) and ulcerative colitis (6.3%). Furthermore, 17.2% of patients were also taking medication capable of causing immunosuppression at the same time they received REBYOTA.1

“People living with IBD in particular are at an increased risk of developing C. diff infection and experience higher rates of recurrence,” said Elizabeth Garner, M.D., M.P.H., Chief Scientific Officer, Ferring Pharmaceuticals U.S. “We are pleased to see that the analysis from the AAT program is consistent with results from the prospective clinical trials. We are committed to ongoing research to help as many patients as possible who are living with recurrent C. diff infection.”

About C. diff infection
C. diff infection is a serious and potentially deadly infection that impacts people across the globe. The C. diff bacterium causes debilitating symptoms, such as severe diarrhea, fever, stomach tenderness or pain, loss of appetite, nausea and colitis (an inflammation of the colon).2 C. diff infection can be the start of a vicious cycle of recurrence, causing a significant burden for patients and the healthcare system.3,4 It has been estimated that up to 35% of C. diff infection cases recur after initial diagnosis and people who have had a recurrence are at significantly higher risk of further infections.5,6,7,8 After the first recurrence, it has been estimated that up to 65% of patients may develop a subsequent recurrence.7,8 Antibiotics – the current standard of care for treatment of C. diff infection – treat the disease but can also be a contributing factor to the cycle of recurrence.2

REBYOTA is a pre-packaged, single-dose 150 mL microbiota suspension for rectal administration consisting of a liquid mix of up to trillions of live microbes – including Bacteroides. REBYOTA is delivered directly to the gut microbiome and is administered by a healthcare professional in one visit.

REBYOTA (fecal microbiota, live – jslm) is indicated for the prevention of recurrence of Clostridioides difficile (C. diff) infection in individuals 18 years of age and older, following antibiotic treatment for recurrent C. diff infection.

Limitation of Use

REBYOTA is not indicated for the treatment of C. diff infection.


  • You should not receive REBYOTA if you have a history of a severe allergic reaction (e.g., anaphylaxis) to REBYOTA or any of its components.
  • You should report to your doctor any infection you think you may have acquired after administration.
  • REBYOTA may contain food allergens.
  • Most common side effects may include stomach pain (8.9%), diarrhea (7.2%), bloating (3.9%), gas (3.3%), and nausea (3.3%).
  • REBYOTA has not been studied in patients below 18 years of age.
  • Clinical studies did not determine if adults 65 years of age and older responded differently than younger adults.

You are encouraged to report negative side effects of prescription drugs to FDA. Visit or call 1-800-332-1088.

Please click to see the full Prescribing Information.

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. In the United States, Ferring is a leader in reproductive medicine and maternal health, uro-oncology and in specialty areas within gastroenterology, including microbiome therapeutics, and orthopaedics. For more information, call 1-888-FERRING (1-888-337-7464) or visit

Connect with us on our dedicated microbiome therapeutics development channels on Twitter and LinkedIn.


  1. Feuerstadt P, et al. Retrospective analysis of the safety and efficacy of fecal microbiota, live – jslm (REBYOTA™) administered under enforcement discretion to patients with Clostridioides difficile infection. Open Forum Infectious Diseases. 31 March 2023. Available at:
  2. Centers for Disease Control and Prevention. What Is C. Diff? 17 Dec. 2018. Available at:
  3. Centers for Disease Control and Prevention. 24 June 2020. Available at:
  4. Feuerstadt P, et al. J Med Econ. 2020;23(6):603-609.
  5. Riddle DJ, Dubberke ER. Clostridium difficile infection in the intensive care unit. Infect Dis Clin North Am. 2009;23(3):727-743.
  6. Nelson WW, et al. Health care resource utilization and costs of recurrent Clostridioides difficile infection in the elderly: a real-world claims analysis. J Manag Care Spec Pharm. 2021;27(7):828-838. doi: 10.18553/jmcp.2021.20395. Epub 2021 Mar 11.
  7. Kelly CP. Can we identify patients at high risk of recurrent Clostridium difficile infection? Clin Microbiol Infect. 2012;18(suppl 6):21–27.
  8. Smits WK, et al. Clostridium difficile infection. Nat Rev Dis Primers. 2016;2:16020. doi: 10.1038/nrdp.2016.20.


For more information, please contact:

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

Release Summary

Ferring Announces Publication of a Retrospective Analysis of Data Evaluating the Safety and Efficacy of REBYOTA in Open Forum Infectious Diseases.

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For more information, please contact:

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