Rifaximin Soluble Solid Dispersion (SSD) Tablets Plus Lactulose for the Treatment of Overt Hepatic Encephalopathy (OHE)

Inclusion Criteria: * Male or female age 18 to 75 years of age (inclusive) at the time of screening. * Females of childbearing potential, defined as a female who is fertile following menarche, must have a negative serum pregnancy test at screening and agree to use an acceptable method of contraception throughout their participation in the study. Note: Female subjects who have been surgically sterilized (e.g., hysterectomy or bilateral tubal ligation) or who are postmenopausal (defined as total cessation of menses for \> 1 year) will not be considered "female subjects of childbearing potential". * Subject is hospitalized with liver cirrhosis and/or OHE and has a confirmed diagnosis of OHE at Baseline. * Subject has a Grade 2 or Grade 3 HE episode according to the HE Grading Instrument (HEGI) following 8 to 12 hours of intravenous (IV) hydration and lactulose treatment. Exclusion Criteria: * Subject has an uncontrolled major psychiatric disorder including major depression or psychoses as determined by the investigator. * Subject has been diagnosed with an infection for which they are currently taking oral or parenteral antibiotics, which cannot be discontinued at time of enrollment. Note: Subjects currently taking Rifaximin are not excluded * Subject shows presence of intestinal obstruction or has inflammatory bowel disease. * Subject has uncontrolled Type 1 or Type 2 diabetes. 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 screening, and demonstrate clinically acceptable blood glucose control at Baseline, as determined by the investigator. * Subject has an active malignancy (exceptions: non-melanoma skin cancers).