Frequently Asked Questions

When was Rebiotix formed?

Rebiotix Inc., a Ferring Company, is a clinical stage biotechnology company founded in 2011 in Roseville, MN to revolutionize the treatment of challenging diseases by harnessing the power of the human microbiome. Rebiotix was acquired by Ferring Pharmaceuticals on April 05, 2018.

What disease categories is Rebiotix focused on?

It is increasingly recognized that restoration of a healthy gut microbiota is necessary for the effective treatment of a potentially large number of challenging diseases. C. diff., which is an urgent public health issue, is one of these diseases. This urgent public health threat is our first targeted disease state. Research demonstrates that antibiotic use may increase the risk of C. diff. infection as well as predisposes to recurrence.

Rebiotix is currently focused on the prevention of recurrent C. diff infection by developing microbiota-based therapies under the MRT™ drug platform.  An oral MRT™ drug platform targeted at C. diff. infection prevention is currently under study. In addition, we are collaborating with leading physicians to study the use of MRT for other challenging diseases including ulcerative colitis, hepatic encephalopathy and multi drug-resistant organisms.

What is our microbiota-based MRT drug platform?

The Rebiotix MRT drug platform is focused on developing formulations that will allow for the delivery of live, human-derived microbes into a sick patient’s intestinal tract to treat disease.

Rebiotix is the first company to take on the challenge of rigorously investigating a microbiota-based drug under the guidance of the U.S. Food and Drug Administration (FDA). Lead Rebiotix product, RBX2660, is targeted at recurrent C. diff. infection. RBX2660, a microbiota-based drug developed on the MRT platform, completed Phase 2 clinical trials, driving the company forward as the leader in microbiome therapy development.

How is MRT different from fecal transplantation?

MRT is very different from fecal transplantation, involving different manufacturing processes, preparation, composition and testing. MRT uses quality control techniques to produce standardized, stabilized product that is ready-to-use in an off-the-shelf format.

Rebiotix is working with the FDA to develop drugs based on the MRT platform including RBX2660 which is targeted at recurrent C. diff. infection.  We are also leveraging our knowledge and experience to develop new therapies and products for other conditions that result from the disruption of the gut microbiota.

What is RBX2660?

Lead Rebiotix product, RBX2660, is targeted at treating recurrent C. diff. infection. It is a non-antibiotic, ready-to-use, liquid microbial suspension packaged for enema delivery. RBX2660 has been investigated in the PUNCH CD 2 trial, a multi-center, randomized, double-blind placebo controlled human clinical trial – the gold standard in clinical trials.  An oral formulation for the prevention of recurrent C. diff. is also undergoing pre-clinical testing.

Special FDA designations for RBX2660, a drug candidate for the prevention of recurrent C. diff.:

  • Fast Track – May 2013
  • Orphan Drug – March 2014
  • Breakthrough Therapy – October 2015

Are you working on an oral formulation?

Yes. Rebiotix is leveraging its clinical and regulatory experience with RBX2660 to develop an oral formulation as part of our MRT drug platform. RBX7455 is targeted at C. diff. infection prevention. An oral, room temperature stable MRT formulation may enable easier application for repeat dosing. The oral formulation is being assessed in a physician-sponsored clinical study.

What is C. diff.?

Clostridium difficile (C. diff.) is a type of bacteria that can cause diarrhea, fever, abdominal pain, nausea, colitis, and in more serious cases, shock and death.

How do people get infected with C. diff.?

C. diff. can be found in many places in the environment and is passed in the feces. A person can become infected by touching a contaminated surface or object.

C. diff. is plentiful in the healthcare environment- on hands, stethoscopes, bedding, telephones and furniture – but also in lower levels in the general community. The bacteria forms spores that are resistant to heat, acid, and antibiotics and can live outside of the body for a very long time which increases the risk for C. diff. transmission.

This infection, which may be life-threatening in some individuals, is usually acquired in the hospital or in an outpatient healthcare setting after treatment with an antibiotic.

Not everyone who ingests C. diff. bacteria develops symptoms. Symptoms occur when the balance of microbes present in the gut is disturbed- may occur with antibiotic use- which then enables the C. diff. bacteria to dominate. Older people who come into contact with the healthcare environment, have a compromised immune system, and have taken antibiotics recently are at particular risk.

What is recurrent C. diff.?

Approximately 25% of people who have a C. diff. infection will experience symptoms again despite what appears to be an initially successful cure with antibiotics.1 This is called recurrent C. diff.

Recurrent C. diff. is especially challenging to treat. Each additional recurrence predisposes to a higher risk of another recurrence – up to 65% after multiple prior occurrences.1

Although antibiotics may contribute to the cycle of recurrence, ironically, recurrent C. diff. is typically treated with more antibiotics. However, treating recurrent C. diff. with more antibiotics just perpetuates disruption of the gut microbiota potentially putting the patient at risk of further recurrences.

What is the unmet need for recurrent C. diff.?

Currently, there is no FDA-approved treatment for patients with recurrences of C. diff.

Fecal transplants have become an increasingly used option for the treatment of recurrent C. diff. infection. However, fecal transplants are not FDA approved or standardized. They are labor intensive and cumbersome procedures with limited availability.

C. diff. infection places an enormous burden on the healthcare system, resulting in $4.8 billion in excess healthcare costs in the U.S. in acute-care facilities alone, according the 2008 data.2


  1. Kelly CP. Can we identify patients at high risk of recurrent Clostridium difficile infection? Clin Microbiol Infect. 2012; 18 (Suppl. 6): 21–27.
  2. Dubberke ER, Olsen MA. Burden of Clostridium difficile on the healthcare system. Clin Infect Dis. 20012;55(S2):S88-92.