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Completed Phase 1 Interventional Accepts healthy volunteers

The Effect of Milk Thistle on the Pharmacokinetics of Indinavir

ClinicalTrials.gov ID: NCT00011635

Public ClinicalTrials.gov record NCT00011635. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

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Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

Complementary and alternative medicines are widely used in the HIV-infected population. Recent data have shown serious drug interactions between certain complementary medicines and protease inhibitors. Silymarin (Milk thistle) is a commonly used dietary supplement in HIV-infected patients for treatment of hepatitis or as a hepato-protectant. Data are available suggesting that it may alter cytochrome P4503A4-mediated drug metabolism. To evaluate the effect of milk thistle on the protease inhibitor, indinavir (IDV), ten healthy subjects will receive IDV (Crixivan) alone and in combination with an over-the-counter silymarin preparation. IDV will initially be administered alone at a dose of 800 mg Q8H for four doses and serial samples will be collected for determination of IDV pharmacokinetics after the morning dose on day 2. Subjects will then initiate therapy will milk thistle using a standardized formulation and dose for three weeks after which subjects will then again take 4 doses of IDV and have serial samples collected for IDV plasma concentrations. There will then be a 11-day washout period with no drugs, after which IDV will again be given for 4 doses and samples will be collected evaluate the offset of the effects of milk thistle. To examine the effect of milk thistle on other CYP450 pathways, subjects will receive a single dose of caffeine and dextromethorphan and have urine collected before and after milk thistle, and after the washout period. Indinavir, caffeine, and dextromethorphan concentrations in plasma or urine will be determined using validated HPLC methods. Steady-state noncompartmental parameters of indinavir in the presence and absence of milk thistle will be determined. Pharmacokinetic parameters will be compared using ANOVA that will include factors for a period effect and a treatment effect. Statistical analyses will include calculation of the mean ratio of the AUC in the treatment phases compared to IDV alone and determination of 95% confidence intervals. This study will help define the drug interaction potential of complementary and alternative therapies in HIV-infected patients.

Study identification

NCT ID
NCT00011635
Recruitment status
Completed
Study type
Interventional
Phase
Phase 1
Enrollment
20 participants

Conditions and interventions

Eligibility (public fields only)

Age range
Not listed
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Jan 31, 2001
Primary completion
Not listed
Completion
May 31, 2001
Last update posted
Mar 3, 2008

2001

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Warren G. Magnuson Clinical Center (CC) Bethesda Maryland 20892

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT00011635, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Mar 3, 2008 · Synced Sep 3, 2026

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The complete protocol, eligibility criteria, and contact information for NCT00011635 live on ClinicalTrials.gov.

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