Data for Ferring’s RBX2660 Published in BMC Infectious Diseases: “Durable Reduction of Clostridioides difficile Infection Recurrence and Microbiome Restoration after Treatment with RBX2660: Results from an Open-Label Phase 2 Clinical Trial”
- Primary objective was to compare treatment success of RBX2660 to historical control group
- A key secondary outcome was the safety profile of RBX2660 through 24 months after treatment
- Post hoc analysis indicated that 91% of evaluable responders remained CDI occurrence-free to 24 months after treatment
Parsippany, NJ, USA – March 15, 2022 – Ferring Pharmaceuticals today announced that BioMed Central (BMC) Infectious Diseases has published its open-label Phase 2 trial data, in which RBX2660 met its primary efficacy endpoint demonstrating a 79% treatment success rate for the reduction of recurrent Clostridioides difficile infection (CDI) versus 31% for the historical control arm. Treatment success was defined as the absence of CDI diarrhea without the need for retreatment of CDI at eight weeks. RBX2660 is an investigational, potential first-in-class microbiota-based live biotherapeutic.
Results from post hoc analysis showed that clinical reduction of CDI recurrence by RBX2660 also correlated with microbiome changes. These changes were observed within seven days after treatment and were sustained through the end of 24-month post-treatment follow-up.
“To our knowledge, this is the first study to report CDI-free rates for 24 months post treatment and suggests a potential long-term benefit with a microbiota-based live biotherapeutic in reducing CDI recurrence,” said Robert Orenstein, DO, Chairman, Division of Infectious Diseases, Mayo Clinic in Arizona, and the lead author of the study.
About the Study
The Phase 2 open-label study was conducted across 29 medical centers in the United States and Canada with 162 participants enrolled. One hundred and forty-two participants were evaluable for the primary endpoint at eight weeks and 107 completed the study with 24 months follow-up. Participants were age 18 years or older with a diagnosis of recurrent CDI who also had at least two documented recurrent episodes of CDI after a primary episode and completed two rounds of standard oral antibiotic therapy or experienced at least two documented episodes of severe CDI resulting in hospitalization. Study participants received up to two doses of RBX2660 seven days apart. Results were compared against a historical control group, identified through a retrospective chart review of matched recurrent CDI patients treated with antibiotics.
The primary efficacy endpoint (treatment success) was defined as the absence of CDI diarrhea without the need for retreatment for CDI and was determined at the eight-week office visit. A secondary outcome was the safety profile of RBX2660 including adverse events and CDI occurrence through 24 months after treatment. A post hoc analysis evaluated RBX2660 responders who remained CDI occurrence free up to 24 months after treatment.
Overall, RBX2660 demonstrated a treatment success rate at 8 weeks of 79% (112/142), compared with 31% (23/75) for the historical control group (p<0.0001). Safety data in the study included an extended follow-up of 24-months after treatment. Most treatment-emergent adverse effects (TEAEs) were mild to moderate in severity and predominantly gastrointestinal related. The post hoc analysis indicated that among the RBX2660-treated evaluable population (n=112), 97% (n=109/112) remained CDI-free at six months, 95% (n=101/106) were CDI-free at 12 months, and 91% (n=88/97) remained CDI-free at 24 months after the last received treatment. RBX2660 also demonstrated clinical reduction of CDI recurrence correlated with microbiome changes—significantly increased abundance of two important classes of bacteria – Bacteroidia and Clostridia – and reduced an abundance of Gammaproteobacteria and Bacilli. This outcome was sustained 24 months after treatment.
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).1 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.1,2,3
C. difficile infection often is the start of a vicious cycle of recurrence, causing a significant burden for patients and the healthcare system.4,5 Up to 35% of CDI cases recur after initial diagnosis1,2 and people who have had a recurrence are at significantly higher risk of further infections.6,7,8,9 After the first recurrence, it has been estimated that up to 65% of patients may develop a subsequent recurrence.8,9
RBX2660 is a potential first-in-class microbiota-based live biotherapeutic studied to deliver a broad consortium of diverse microbes to the gut to reduce recurrent C. difficile infection after antibiotic treatment. 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 www.ferring.com, 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.
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- Centers for Disease Control and Prevention. What Is C. Diff? 17 Dec. 2018. Available at: https://www.cdc.gov/cdiff/what-is.html.
- Centers for Disease Control and Prevention. Biggest Threats and Data, 14 Nov. 2019. Available at: https://www.cdc.gov/drugresistance/biggest-threats.html
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- Centers for Disease Control and Prevention. 24 June 2020. Available at: https://www.cdc.gov/drugresistance/pdf/threats-report/clostridioides-difficile-508.pdf.
- Feuerstadt P, et al. J Med Econ. 2020;23(6):603-609.
- Riddle DJ, Dubberke ER. Clostridium difficile infection in the intensive care unit. Infect Dis Clin North Am. 2009;23(3):727-743.
- Nelson WW, et al. Health care resource utilization and costs of recurrent Clostridioides difficile infection in the elderly: a real-world claims. J Manag Care Spec Pharm. Published online March 11, 2021.
- Kelly, CP. Can we identify patients at high risk of recurrent Clostridium difficile infection? Clin Microbiol Infect. 2012; 18 (Suppl. 6): 21–27.
- Smits WK, et al. Clostridium difficile infection. Nat Rev Dis Primers. 2016;2:16020. doi: 10.1038/nrdp.2016.20.