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

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

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.

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.

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.