Randomised Controlled Trial of Mechanistic Effects of Rifaximin in Cirrhosis and Chronic Hepatic Encephalopathy
Randomised Controlled Trial of Mechanistic Effects of Rifaximin in Cirrhosis and Chronic Hepatic Encephalopathy
Patients with cirrhosis are particularly prone to infection which is frequently a precipitant
 of hepatic encephalopathy, renal failure and circulatory collapse. Bacterial infections are
 of particular concern in patients with cirrhosis because they are poorly tolerated. Sepsis
 and associated endotoxaemia whereby bacteria produce inflammatory particles occur in
 approximately 40% of hospitalized patients with cirrhosis and is a major cause of death.

 Gut-derived and blood-borne pathogens can induce an inflammatory response within the liver
 and spleen, which are the major organs that remove bacteria and their endotoxin (such as
 lipopolysaccharide - LPS and bacterial DNA itself) from the bloodstream. Several mechanisms
 have been identified and proposed in this process which depends upon a balance between the
 barrier functions of the gut and the 'detoxifying' capacity of the liver. People with
 established liver cirrhosis have been shown to have escape of endotoxin into the bloodstream
 produced by bacteria that reside in their intestines, which becomes more permeable or
 'leaky'.

 Gut dysfunction is defined by changes in the types of bacteria within the gut and in overall
 permeability allowing bacterial products which would otherwise be contained within the gut to
 travel into the bloodstream and lymphatic system with detrimental effects elsewhere in the
 body. This passage of bacterial products is termed bacterial translocation, and it's effects
 on the liver and general immune system can be then be measured.

 It has now become recognised that certain types of white blood cells such as neutrophils and
 monocytes become dysfunctional and this predisposes to infection and may also have a more
 direct pathogenic role in hepatic encephalopathy. Thus neutrophil and monocytes may be a
 novel pharmacotherapeutic target in a condition where current therapies such as bowel
 aperients (e.g. lactulose) are inadequate. A therapeutic strategy utilising Rifaximin, a
 non-absorbable antibiotic, to modulate gut bacterial which produce ammonia, a chemical known
 to be important in the cause of hepatic encephalopathy, could potentially lower gut-derived
 systemic inflammation, endotoxaemia, infection and organ dysfunction in this population
 improving outcomes and prolonging transplant-free survival.

 We therefore plan to test if Rifaximin positively affects markers of immune dysfunction in
 patients with liver cirrhosis experiencing chronic hepatic encephalopathy after 30 days of
 treatment, as our primary research question.

 Positive results from this study would support further trials into the potential benefit of
 using Rifaximin to improve immune function, as well as reduce the recurrence of hepatic
 encephalopathy, in patients with liver cirrhosis.
Overview

 The study will be designed and conducted as a double blind placebo controlled randomised
 controlled trial - Clinical Trial of an Investigational Medicinal Product.

 This study will be performed on patients referred to King's Liver Unit for further assessment
 and management of chronic overt hepatic encephalopathy (≥ Grade 1) or with ≥2 episodes of
 overt hepatic encephalopathy in the previous 6 months.

 The study will be performed on 50 patients with cirrhosis and chronic hepatic encephalopathy
 [25 Rifaximin and 25 placebo] aged between 18 and 75 years managed within the Liver Unit at
 King's College Hospital which is the largest tertiary Liver Transplant Centre within the UK.
 For the purposes of this study a patient will be considered to have cirrhosis if they fulfil
 2 out of 3 diagnostic criteria of confirmatory liver histology, biochemistry and/or
 radiologic findings consistent with cirrhosis/portal hypertension, and are presenting with
 chronic persistent overt hepatic encephalopathy (≥ grade 1) or with ≥2 episodes of overt
 hepatic encephalopathy in the previous 6 months.

 Patient demographics, clinical details (including Westhaven hepatic encephalopathy grade) and
 blood haematology, biochemistry (including venous ammonia), microbiology data and neutrophil
 function will be assessed and collated at baseline and following 30 and 90 days of Rifaximin
 therapy or placebo. Intestinal permeability will be assessed using the intestinal
 disaccharide test. Faecal microbiota analysis will be performed by deep pyrosequencing
 techniques and plasma endotoxemia will be measured (lipopolysaccharide levels) with bacterial
 DNA quantification as a marker of bacterial translocation. These will all be measured at 3
 time points: baseline and at 30 and 90 days after initiation of Rifaximin therapy or matching
 placebo.

 Investigations

 Patients will undergo intestinal functional tests within 7 days of recruitment, whereby they
 will be administered a test solution of not more than a cupful (150mls) of different types of
 non-absorbable sugars, which are drunk in liquid form by the participants. Prior to
 ingestion, baseline samples will be obtained as follows:

 i) blood samples - for analysis of intestinal & immune (dys)function, and metabonomic
 analysis ii) urine sample - for intestinal (dys)function & metabonomic analysis iii) stool
 sample - for faecal biomarker and microbiota analysis

 1v) ascitic sample (if clinically indicated) - surplus fluid will be analysed for bacterial
 translocation and immune (dys)function

 Once the test solution has been ingested, blood samples will be obtained via a cannula which
 is placed in a vein, usually in the arm, prior to the start of the test, to allow further
 sampling without causing discomfort to the patient. A total of 15 samples will be obtained
 over a 5 hour period, with intervals ranging between 20-30mins, of not more than 6mls per
 sample. At the end of the test, at a 5 hour interval, a further urine sample will be
 collected to allow for intestinal functional testing. This is exactly the same procedure as
 that specified in the approved 'The Gut-Liver Axis in Liver Disease & Liver Transplantation'
 study (REC ref: 12/LO/1417).

 Where participants are undergoing sampling of ascitic fluid for clinical reasons any fluid in
 excess of pathology's requirements will be analysed along with peripheral blood samples.
 Ascitic samples will only be taken from patients in whom a decision has been made to take
 these samples for clinical reasons (this decision will not be that of the investigator). No
 increased volume of such sample would be required.

 Clinical outcomes (development of recurrent overt hepatic encephalopathy, organ failure and
 infection) will be recorded for a total of 90 days.

 Analysis of samples - sites

 Blood, urine and ascitic samples will be analysed in the Institute of Liver Studies and
 King's College Hospital laboratories where various tests to determine intestinal and immune
 function will be undertaken. Stool samples will be analysed both at laboratories at King's
 College Hospital and at the Franklin-Wilkins Building, King's College London, where faecal
 biomarkers and faecal microbiota analyses will be performed, respectively. Metabolic analyses
 for metabonomic profiling will be carried out at Imperial College London (both at St Mary's
 Hospital and at the South Kensington Campus).

 Protocol

 A more detailed list of the tests and analyses to be performed is to be found in the
 protocol. Study-specific flow charts have also been provided for a step-by-step
 representation of the study, visually representing the study process including participant
 recruitment, randomisation, sampling protocols and analyses at the three time points and
 follow-up visits.
Inclusion Criteria:

 -  Patients with established cirrhosis complicated by hepatic encephalopathy

 -  For the purposes of this study a patient will be considered to have cirrhosis if they
 fulfil two out of the three diagnostic criteria of confirmatory liver histology,
 biochemistry and/or radiologic findings consistent with cirrhosis/portal hypertension,
 and

 -  are presenting with chronic persistent overt hepatic encephalopathy (≥ grade 1) or
 with ≥2 episodes of overt hepatic encephalopathy in the previous 6 months.

 Exclusion Criteria:

 -  Age ≤18 or ≥75.

 -  Evidence of disseminated malignancy.

 -  Known coeliac or inflammatory bowel disease.

 -  Evidence of intestinal failure, intestinal obstruction and / or previous bowel
 resection.

 -  Pre-existing immunosuppressive states including HIV infection and chronic
 granulomatous diseases.

 -  Anti-inflammatory drug use e.g non-steroidals and immunomodulatory drug use e.g.
 prednisolone and azathioprine.

 -  Known hypersensitivity to rifaximin or rifamycin-derivatives

 -  Already receiving concomitant oral or parenteral antibiotic therapy e.g norfloxacin.

 -  Infection with clostridium difficile or stool testing positive for clostridium
 difficile toxin in the previous 3 months.

 -  Pregnancy or breast feeding women