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Be Proactive About
Your Liver Cirrhosis

Take steps now to potentially
prevent hepatic encephalopathy

About the Red-C 3131 Study

Hepatic encephalopathy (HE) is a complication of liver cirrhosis (liver damage). It effects nearly half of people with cirrhosis. Because of the damage, the liver doesn’t work as well as it should, and some toxins stay in the body. HE occurs when too many toxins build up in the bloodstream and reach the brain. It can cause symptoms like:

  • Confusion
  • Personality changes
  • Lack of energy
  • Inappropriate behavior
  • Sleep problems
  • Loss of small hand movements
  • Tremors in hands and arms

This study is looking to see if a study medicine, rifaximin, can safely delay or prevent HE. Adults who have been diagnosed with advanced liver cirrhosis, but who do not have HE yet may be eligible to join.

Who can participate in this study?

Participants may be eligible for the study if they:

  • Are between the ages of 18 and 70
  • Have a diagnosis of advanced liver cirrhosis
  • Have not been diagnosed with overt HE (the severe form of HE)
  • Do not experience any cognitive issues due to HE or any other illness
  • Do not have active COVID-19 infection

What can participants expect?

Participants will be in the study for up to 80 weeks (about 1.5 years). They will attend up to 20 study visits, including 14 visits to the clinic and 7 telephone check-ins. The study includes the following periods:

Screening Period
(Up to 4 weeks)

Will last up to 4 weeks and may take place over more than one visit. Participants will have tests done to see if they qualify for the study.

Study Treatment Period
(72 weeks)
  • Once participants are found eligible, they will be randomly (like the flip of a coin) assigned to one of two treatment groups: the study medicine or the placebo (which contains no active ingredients). This means participants have a 50/50 chance of receiving the study medicine.
  • Both study groups will take the study medicine or placebo as a pill twice a day.
  • The study is double-blind, which means neither the participants nor study team will know which treatment they are receiving.
  • Participants who develop OHE (overt HE, the severe form of HE) will be treated by the study team and followed for the remainder of the study.
Follow-up Period
(4 weeks)

Participants will attend a follow-up visit 4 weeks after they stop taking the study medicine. At this visit, the study team will perform a final round of tests will have tests to check their health and effect of the safety of the study medicine. Even if participants stop taking the study medicine or leave the study early, we ask they still attend an End of Treatment Visit and the Follow-up Visit.

Find a study center
Why is clinical research important?

Before a new therapy can be made available to the general public, multiple studies involving patient volunteers must be conducted to evaluate the safety and effectiveness of the therapy. These studies, referred to as clinical trials, are regulated by the Food and Drug Administration (FDA) in the United States and by similar regulatory agencies worldwide. Participation in this will help us understand whether the study medicine is effective in delaying or preventing HE in adults with liver cirrhosis.

Why volunteer for a research study?

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Frequently asked questions

Participants will be in the study for up to 80 weeks (about 1.5 years). They will attend up to 20 study visits, including 14 visits to the clinic and 7 telephone check-ins.

While participants will not receive any compensation for taking part in this study, they will receive the following at no cost:

  • The study medicine or placebo
  • Any study-related care at no cost.
  • They may also be reimbursed for reasonable study-related travel costs

The study medicine, rifaximin, is currently FDA approved as an antibiotic to treat diarrhea from irritable bowel syndrome, traveler’s diarrhea and others. It is often prescribed off-label to treat HE. Please note that if you take antibiotics, there is a chance you could get a C. diff infection (an infection known to occur after receiving antibiotics). There is also a potential for antibiotic resistance development.

During a clinical study, you’ll receive the medication that is being studied. If you participate, you may also have the following procedures performed to monitor your health: vital signs, blood work, physical exams or other types of assessments that are necessary to gather the required information about the study medication. In some studies, you may not receive the study medication, but instead receive a placebo. All study volunteers are always closely monitored by clinic staff and the medical team to ensure their safety.

A placebo looks like the study drug being tested, but it doesn’t have any active ingredients. In placebo-controlled research, one group is given the inactive treatment, while another group is given the active treatment. This is the best way to find out if the treatment being tested works better than receiving no treatment at all.

Participation in any clinical study is completely voluntary. Your decision to participate – or not participate – in this clinical study will have no effect on the medical care that you receive now or in the future. If you are eligible and choose to participate in the study, you may leave the clinical study at any time, and for any reason.

There are many reasons to participate in clinical research. For starters, it allows participants to play a more proactive role in their own health by receiving a new treatment for an ongoing disease or condition. Participants also play an important part in bringing much needed drugs to market, benefitting thousands of people who also have the disease or condition. In many cases, this can be life changing. In addition to benefitting those with the disease, participants may be paid for their time and travel expenses.

Every clinical trial must be reviewed, and is continually monitored, by a regulatory review committee to ensure the risks are as low as possible and are worth any potential benefits to the study participant. As a volunteer, you have the right to discontinue your participation and leave the study at any time and for any reason, with no penalty or loss of benefits to which you are otherwise entitled to.

If you decide this clinical research study is appropriate for you, the study doctor and staff will explain the investigation research study, then ask you to review an informed consent document. This document will describe the research, including its purpose, length, procedures, possible known risks and benefits of participating, and what is expected of you if you take part. After you have reviewed this document, you can decide whether or not to sign the document and volunteer to participate in the study.

Salix Pharmaceuticals, Inc. a division of Bausch Health US, LLC is responsible for conducting this clinical study. To learn more, please visit Bausch Health US.

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