Steady-State Pharmacokinetics of Rifaximin 550 mg Tablets in Healthy and Hepatically Impaired Subjects

Study Overview
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Brief Summary
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The primary objective of this study is to characterize the steady state plasma

Detailed Description
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The primary objective of this study is to characterize the steady state plasma PK of rifaximin (550 mg BID) in subjects with severe hepatic impairment (MELD 19 to 25 and MELD >25), as well as healthy subjects with normal hepatic function.

Official Title
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Open Label Study to Evaluate the Steady-State Pharmacokinetics of Rifaximin 550 mg Tablets in Healthy Subjects and Subjects With Severe Hepatic Impairment

Conditions
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Severe Hepatic Impairment

Intervention / Treatment
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* Drug: Rifaximin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hepatically impaired subjects will be ≥18 years of age, have a diagnosis of liver cirrhosis and a MELD score of ≥19 at Screening. Note: At least 6 of the hepatically impaired subjects will have a MELD score of >25. Exclusion Criteria: Subject has known allergy to rifaximin, rifampin, or other rifamycins, excipients and/or vehicles used in the formulation, or any other clinically significant allergies. Subject has participated in an investigational drug or device study within 30 days prior to Day 1 (Baseline). Subject has any concurrent illness (other than liver cirrhosis), disability or circumstance that may affect the interpretation of clinical data, could cause noncompliance with treatment or visits or otherwise contraindicates participation in this study in the opinion of the investigator.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: open-label, repeat-dose, parallel-design study in 12 subjects with severe hepatic impairment and 6 healthy subjects with normal hepatic function.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Rifaximin<br>Rifaximin 550 mg BID | Drug: Rifaximin<br>* Rifaximin 550 MG BID<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum Observed Plasma Concentration (Cmax) | Maximum observed plasma concentration (Cmax) of rifaximin and 25-desacetyl rifaximin, if measurable | 7 days | 
| Time of the Maximum Concentration (Tmax) | Time of the maximum concentration (Tmax) of rifaximin and 25-desacetyl rifaximin, if measurable | 7 days | 
| Area Under the Plasma Concentration Versus Time Curve (AUC) During the 12-hour Dose Interval | Area under the plasma concentration versus time curve (AUC) during the 12-hour dose interval of rifaximin and 25-desacetyl rifaximin, if measurable | 7 days |