A subject will not be eligible for inclusion in this study if any of the following criteria apply:
Current or Past Medical History
1. Subject has history of a major psychiatric disorder including uncontrolled major depression or
controlled or uncontrolled psychoses within the past 24 months prior to signing the informed consent
(Diagnostic and Statistical Manual of Mental Disorders, 4th.) that in the opinion of the investigator
would prevent completion of the study, interfere with analysis of study results, or negatively impact
the subject’s participation in the study.
2. Subject has history of alcohol abuse or substance abuse within the past 3 months prior to signing the
informed consent (Diagnostic and Statistical Manual of Mental Disorders, 4th.)
3. Subject has documented cholestatic liver disease such as primary sclerosing cholangitis or primary
4. Subject has had prophylactic variceal banding or is scheduled to undergo prophylactic banding
within 30 days of randomization.
5. Subject has been diagnosed with an infection for which they are currently taking oral or parenteral
6. Subject has significant hypovolemia, or any electrolyte abnormality that can affect mental function
(eg, serum sodium < 125 mEq/L, serum calcium > 10 mg/dL).
7. Subject has severe hypokalemia as defined by a serum potassium concentration < 2.5 mEq/L.
8. Subject is anemic, as defined by a hemoglobin concentration of ≤ 8 g/dL.
9. Subject has renal insufficiency with a creatinine of ≥ 1.5 mg/dL.
Note: Laboratory tests related to Inclusion/Exclusion criteria can be repeated once, before
considering subject as a Screening Failure (given all other Inclusion/Exclusion criteria are met/notmet
respectively) at the discretion of the Investigator.
10. Subject shows presence of intestinal obstruction or has inflammatory bowel disease.
11. Subject has uncontrolled Type 1 or Type 2 diabetes, or diabetes requiring insulin. Note: Subjects
with controlled diabetes may be enrolled if they are on stable doses of oral hypoglycemic drugs for at
least 3-months prior to randomization, and demonstrate clinically acceptable blood glucose control
within 30 days of randomization in the opinion of the investigator.12. Subject has a history of seizure disorders.
13. Subject has unstable cardiovascular or pulmonary disease, categorized by a worsening in the disease
condition that requires a change in treatment or medical care within 30 days of randomization.
14. Subject has an active malignancy within the last 5 years (exceptions: basal cell carcinomas of the
skin, or if female, in situ cervical carcinoma that has been surgically excised).
15. Subject has hepatocellular carcinoma (HCC). Note: Alpha-fetoprotein (AFP) concentration will be
measured at screening. If the AFP is greater than 200 ng/mL, the subject is excluded from
participation in the study. If the AFP is above the upper limit of normal and
≤ 200 ng/mL, cross-sectional imaging techniques should be used to rule out HCC.
16. Subject has any condition or circumstance that adversely affects the subject or could cause
noncompliance with treatment or visits, may affect the interpretation of clinical data, or may
otherwise contraindicate the subject’s participation in the study.
17. If female, subject is pregnant or at risk of pregnancy, or is lactating.
18. Known varicella, herpes zoster, or other severe viral infection within 6 weeks of randomization.
19. Known human immunodeficiency virus (HIV) infection.
20. Subject has a positive stool test for Yersinia enterocolitica, Campylobacter jejuni, Salmonella,
Shigella, ovum and parasites, and/or Clostridium difficile (C. difficile). NOTE: Results of stool tests
must be confirmed as negative prior to randomization.
21. Subject has a history of tuberculosis infection and/or has received treatment for a tuberculosis
infection. If subject has had a previous positive skin test for tuberculosis antigen then they must
have a current negative chest X-ray to be eligible and must not have received previous treatment.
22. Subject is an employee of the site that is directly involved in the management, administration, or
support of this study or is an immediate family member of the same.
23. Subject has a history of hypersensitivity to rifaximin, rifampin, rifamycin antimicrobial agents, or
any of the components of Rifaximin SSD.
24. Subject used any investigational product or device, or participated in another research study within
30 days prior to randomization.