MedTrace Logo

The Effect of Milk Thistle on the Pharmacokinetics of Indinavir

NCT00011635 · Status: COMPLETED · Phase: PHASE1 · Type: INTERVENTIONAL · Enrollment: 20

Last updated 2008-03-04

No results posted yet for this study

Summary

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.

Conditions

  • HIV Infection
  • Healthy

Interventions

DRUG

Silymarin (milk thistle)

Sponsors & Collaborators

  • National Institutes of Health Clinical Center (CC)

    lead NIH

Study Design

Purpose
TREATMENT

Eligibility

Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2001-02-28
Completion
2001-06-30

Countries

  • United States

Study Locations

More Related Trials

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT00011635 on ClinicalTrials.gov