Intervention: Rifaximin
Trial phase: Phase 1 | Phase 2
ATC code: A07AA11 | D06AX11
SMILES: COC1C=COC2(C)Oc3c(C)c(O)c4c(O)c(c5c(nc6cc(C)ccn65)c4c3C2=O)NC(=O)C(C)=CC=CC(C)C(O)C(C)C(O)C(C)C(OC(C)=O)C1C
Sex: All
Age groups: Adult | Older Adult
Healthy volunteers: No
Participants at risk: 43
Group description: Human immunodeficiency virus (HIV) infected subjects with viral suppression on antiretroviral (ART). Double-blinded/placebo controlled trial with cross-over design.

Rifaximim: subject will receive three capsules of rifaximin (183.3 mg each) by mouth twice daily (total 1100 mg Daily).
Eligibility criteria:
PARTICIPANT INCLUSION CRITERIA:

Patients who have agreed in the course of other research studies to have their records reviewed will have the following elements evaluated from their existing records: age, history of human immunodeficiency virus (HIV) infection, antiretroviral therapy (ART) history and viral loads prior to informed consent, or else these elements will be assessed after informed consent. All blood draws to assess eligibility will be completed after obtaining informed consent. To participate in this study the criteria listed below will need to be met.

Subjects must be 18 years of age or older.
Able and willing to provide written informed consent
Must have a history of documented HIV infection.
HIV infection if not previously documented at host institutions will need to be documented by a plasma human immunodeficiency virus (HIV) ribonucleic acid (RNA) viral load, rapid HIV test or any other licensed enzyme-linked immunosorbent assay (ELISA) test and confirmed by another test using a different method such as a rapid HIV test, Western Blot, HIV culture, HIV antigen, HIV pro-viral deoxyribonucleic acid (DNA) at any time prior to study entry.
ART- treated subjects who are virologically suppressed for greater than or equal to 3 years (1095 days). To meet this criteria all documented viral loads in the 3 years (1095 days) prior to the screening visit must be below the lower limit of detection [LLD] using Food and Drug Administration (FDA)-approved standard assays (i.e. <50 copies/mL) with the following clarification: In each of the three prior years, subjects experiencing a single blip [i.e. viral loads above the lower limit of detection, LLD] may be included provided they satisfy the following criteria: the blips are below 200 copies/ml, and the blip is surrounded (i.e the preceding and succeeding viral loads) by undetectable HIV-1 RNA level measurements. That is all viral loads must be below LLD EXCEPT for up to one blip. In any 12 month period.
Viral RNA level < 50 c/ml at Screen 1.
A minimum of 2 HIV-1 RNA levels that are below the lower limit of detection using standard assays will be required during the 12 month period prior to their screening visit. As assay characteristics across the sites can vary, LLD for the assay will be used to define whether or not a subject is suppressed.
Stable dose of statin therapy for 6 months if receiving statin therapy.
No known allergy or contraindication to the use of rifamycin compounds such as rifampin, rifabutin or rifaximin. .
The effect of rifaximin on the developing human fetus are unknown, therefore subjects must be willing to use two methods of contraception (one of which must be a barrier method) during the study period. Adequate methods of birth control include: tubal ligation, hysterectomy, condoms (male or female) with or without a spermicide; diaphragm or cervical cap with spermicide; intrauterine device; any of the methods that require a prescription (such as contraceptive pills or patch, Norplant, Depo-Provera, and others) or a male partner who has previously undergone a vasectomy.

The following elements will be assessed with a blood draw and after obtaining informed consent.

Absolute Neutrophil count (ANC) greater than or equal to 750/mm(3)
Hemoglobin greater than or equal to 10.0 g/dL for women and Hemoglobin 11.0 g/dl for men
Platelet count greater than or equal to 75,000/mm(3)
Estimated Glomerular Filtration Rate (eGFR) >60 mL/min, eGFR will be calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation
Confirmed serum glutamate pyruvate transaminase (SGPT)/serum glutamate oxaloacetate transferase (SGOT) less than or equal to 3 times the upper limit of normal (ULN)
International Normalized Ratio (INR) less than or equal to the upper limit of normal (ULN) for the assay
Negative urine pregnancy test of child bearing potential at randomization
No evidence of active hepatitis B or hepatitis C (active hepatitis B will be defined as a positive hepatitis B surface antigen present on a single determination, whereas a positive result on hepatitis C RNA will be considered as evidence of active hepatitis C)

All routine laboratory testing used to determine safety will be completed within the 70 days prior to randomization.

EXCLUSION CRITERIA:

Known bleeding diathesis (for example a diagnosis of hemophilia or Von Willebrand disease)
Active drug use or alcohol abuse/dependence, which in the opinion of the investigators will interfere with the patients ability to participate in the study
Serious illness requiring systemic treatment and/or hospitalization within 30 days of screening into the study
Evidence of active opportunistic infections or neoplasms (excluding cutaneous basal cell carcinoma and squamous cell carcinoma) in the 6 months prior to randomization
History of inflammatory bowel disease (Crohn's Disease, ulcerative colitis)
Positive urine pregnancy test at screening (of child bearing potential).
Breastfeeding
Current imprisonment
Concurrent immunomodulatory agents, including systemic corticosteroids in the 12 weeks prior to randomization. Topical, nasal or inhaled corticosteroid use is allowed
Concomitant use of probiotics except yogurt
Chronic antibiotic use such as tetracyclines for acne
Vaccinations within 6 weeks of randomization
Concomitant use of anticoagulants (other than aspirin and nonsteroidal anti-inflammatory drugs (NSAIDS)) is an exclusion criterion for subjects opting in for the colonoscopy. Aspirin and NSAIDs will be discontinued per each institutions requirement before the procedure.
Child-Pugh Class C disease
A prior history of Clostridium difficile colitis
Any condition that precludes the safe administration of conscious sedation for endoscopy (such as decompensated lung or heart disease) will not be able to participate in the colonoscopy aspect of the protocol.