Open-Label Study to Evaluate the Effect of Rifaximin on Midazolam in Normal Healthy Volunteers

This study has been completed.
Information provided by:
Valeant Pharmaceuticals International, Inc. Identifier:
First received: August 27, 2008
Last updated: December 21, 2009
Last verified: December 2009
The primary objective of this study is to determine if rifaximin, administered daily has an effect on the cytochrome P450 (CYP) isoenzyme 3A4, by examining any changes in the pharmacokinetics of midazolam (a CYP3A4 substrate), when co-administered.

Condition Intervention Phase
Drug: rifaximin
Phase 1

Study Type: Interventional
Study Design: Endpoint Classification: Pharmacokinetics Study
Intervention Model: Single Group Assignment
Masking: Open Label
Official Title: A Phase 1, Single Arm, Open-Label Study to Evaluate the Effect of Rifaximin 550 MG Tablets TID on the Pharmacokinetics of Orally Administered Midazolam in Healthy Male and Female Volunteers

Resource links provided by NLM:

Further study details as provided by Valeant Pharmaceuticals International, Inc.:

Primary Outcome Measures:
  • Individual midazolam and rifaximin plasma concentrations and pharmacokinetic parameters will be summarized. [ Time Frame: 21 to 38 days (including a 21 day screening period) ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Overall safety assessments will include the incidence, intensity, and type of adverse events, and clinically significant changes in the patient's physical examination, vital signs and laboratory results. [ Time Frame: 21 tyo 38 days ] [ Designated as safety issue: Yes ]

Enrollment: 24
Study Start Date: September 2008
Study Completion Date: November 2008
Primary Completion Date: October 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
open-label rifaximin 550 mg TID
Drug: rifaximin
550 mg TID

Detailed Description:
This is a single-site, single-arm, open-label, drug-interaction study that examines the effect of rifaximin (RFX), 550 mg 3 times daily (TID; 1650 mg/day), on orally administered (PO) midazolam (MDZ) 2 mg (administered as a 2 mg dose in 1 mL of midazolam HCL Syrup; 2 mg/mL) when dosed for 7 and 14 consecutive days, respectively.

Ages Eligible for Study:   18 Years to 45 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Patient is medically normal
  • Patient has normal laboratory values
  • Patient has the ability to understand the requirements of the study

Exclusion Criteria:

  • HIV
  • Hepatitis B
  • Hepatitis C
  • History of renal, hepatic, endocrine, oncological, gastrointestinal or cardiovascular disease.
  • History of epilepsy, asthma, diabetes, psychosis, glaucoma or severe head injury.
  Contacts and Locations
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Please refer to this study by its identifier: NCT00743912

Sponsors and Collaborators
Valeant Pharmaceuticals International, Inc.
Principal Investigator: William Lewis, MD Covance CRU, Inc
  More Information

Responsible Party: Audrey Shaw, Director Clinical Development, Salix Pharmaceuticals, Inc. Identifier: NCT00743912     History of Changes
Other Study ID Numbers: RFDI1008 
Study First Received: August 27, 2008
Last Updated: December 21, 2009
Health Authority: United States: Food and Drug Administration

Keywords provided by Valeant Pharmaceuticals International, Inc.:

Additional relevant MeSH terms:
Adjuvants, Anesthesia
Anesthetics, General
Anesthetics, Intravenous
Anti-Anxiety Agents
Anti-Infective Agents
Central Nervous System Depressants
Enzyme Inhibitors
GABA Agents
GABA Modulators
Gastrointestinal Agents
Hypnotics and Sedatives
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Nucleic Acid Synthesis Inhibitors
Physiological Effects of Drugs
Psychotropic Drugs
Tranquilizing Agents processed this record on May 30, 2016