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Sponsored by: |
National Institutes of Health Clinical Center (CC) |
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Information provided by: | National Institutes of Health Clinical Center (CC) |
ClinicalTrials.gov Identifier: | NCT00103012 |
This study will examine the interaction of the HIV combination medication lopinavir/ritonavir with the herbal products echinacea, ginseng, and ginkgo biloba. Patients with HIV infection often take herbal products and dietary supplements in addition to their doctor-prescribed medicines to treat the disease, lessen the side effects of anti-viral drugs, and improve their overall well being. Alternative medicines such as these may, however, interfere with the elimination of lopinavir/ritonavir from the body, causing either higher or lower blood levels of these drugs than would be expected. This study will assess in healthy subjects any potential harms of taking echinacea, ginseng, or ginkgo biloba together with lopinavir/ritonavir.
Healthy normal volunteers between 18 and 50 years of age may be eligible for this study. Candidates are screened with a history, physical examination, and blood tests, including an HIV test and a pregnancy test for women. Pregnant women are excluded from the study. Participants come to the NIH Clinical Center after fasting overnight for the following procedures:
Visits 1 and 2: A catheter (plastic tube) is placed in an arm vein to collect blood samples. After the first sample is drawn, the subject takes 8 mg of midazolam syrup and two fexofenadine tablets. Midazolam is a sedative, and fexofenadine (Allegra) is a medicine used to treat allergies. Subjects are given breakfast an hour after taking the drugs. Blood samples are collected at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8 and 24 hours after taking the drugs to measure blood levels of fexofenadine. An extra sample is collected at the 4-hour mark to measure the midazolam level. The catheter is removed after the 8-hour blood draw and subjects are dismissed home. They return the following morning (visit 2) for the 24-hour blood draw.
Visit 3: From 7 to 28 days after visit 1, subjects begin taking lopinavir/ritonavir capsules twice a day by mouth for a total of 29.5 days. On day 15 they return to the clinic for lopinavir/ritonavir blood levels as were done for fexofenadine, except that samples are collected once before breakfast and then at 0.5, 1, 2, 3, 4, 6, 8 and 12 hours after the lopinavir/ritonavir dose. An extra sample is collected for routine tests. The catheter is removed after the 12-hour draw and the subject is dismissed home.
The next morning, subjects begin taking one of the following: echinacea 500 mg 3 times a day; ginkgo biloba 120 mg twice a day; or ginsen...
Condition | Intervention | Phase |
---|---|---|
Healthy |
Drug: Fexofenadine Drug: Midazolam Drug: Lopinovir Drug: Ritonavir |
Phase IV |
Study Type: | Interventional |
Study Design: | Randomized, Open Label, Crossover Assignment, Pharmacokinetics Study |
Official Title: | The Influence of Concurrent Administration of Echinacea Purpurea, Ginkgo Biloba, or Panax Ginseng on the Steady State Pharmacokinetic Profile of Lopinavir/Ritonavir in Healthy Volunteers |
Estimated Enrollment: | 150 |
Study Start Date: | January 2005 |
Arms | Assigned Interventions |
---|---|
A: Experimental
Echinacea administered 500 mg three times daily
|
Drug: Fexofenadine
N/A
Drug: Midazolam
N/A
Drug: Lopinovir
N/A
Drug: Ritonavir
N/A
|
B: Experimental
G. biloba 120 mg twice daily
|
Drug: Fexofenadine
N/A
Drug: Midazolam
N/A
Drug: Lopinovir
N/A
Drug: Ritonavir
N/A
|
C: Experimental
Ginseng 500 mg twice daily
|
Drug: Fexofenadine
N/A
Drug: Midazolam
N/A
Drug: Lopinovir
N/A
Drug: Ritonavir
N/A
|
Patients with HIV commonly use herbal products and dietary supplements in addition to medications prescribed by their physicians. Up to 73% of patients with HIV have reported using some form of complementary or alternative medicine. As such, the potential for clinically significant drug interactions between herbs and antiretrovirals is becoming increasingly appreciated. Despite this awareness, little is known about the effect of commonly used herbal products, such as echinacea, ginkgo biloba, and ginseng, on antiretroviral pharmacokinetics. Interacting herbal supplements have the potential to alter protease inhibitor (PI) plasma concentrations, as has been shown with St. John's Wort and garlic. Drug interactions may potentially increase antiretroviral concentrations, putting patients at risk for toxicities, or lower drug concentrations below the threshold of viral susceptibility, putting patients in jeopardy of antiretroviral failure. The protease inhibitors lopinavir and ritonavir both rely principally on cytochrome P450 (CYP) 3A4 metabolism for their elimination. In addition, both drugs are substrates for the transport protein p-glycoprotein (P-gp), which may also contribute to their distribution and elimination.
The primary purpose of this investigation is to determine whether the herbal supplements Echinacea purpurea, ginkgo biloba, and Panax ginseng alter the pharmacokinetic properties of the HIV protease inhibitor combination lopinavir/ritonavir (LPV/r). Secondary objectives will assess the influence of E. purpurea, G. biloba, and P. ginseng on (1) CYP3A enzyme activity and (2) P-gp mediated drug transport. This is an open label pharmacokinetic study that will be performed on an outpatient basis. A total of 42 study participants who have met inclusion criteria will be sequentially divided into one of 3 groups, such that 14 subjects each will receive LPV/r alone and in combination with either E. purpurea, G. biloba, or P. ginseng.
Subjects will receive single oral doses of fexofenadine 120 mg and midazolam 8 mg followed by plasma collection for determination of baseline CYP3A and P-gp phenotypes (Study Day 1). Between 7 and 28 days after Day 1, subjects will begin taking LPV/r (400mg/100mg twice daily x 29.5 days), returning to the NIH on Day 15 of LPV/r for post-dose plasma collection and determination of lopinavir and ritonavir concentrations. On Day 16 participants will begin taking either E. purpurea (500mg, three times daily), G. biloba extract (120 mg, twice daily), or P. ginseng (500 mg, twice daily) for 28 days. On the 30th day of LPV/r (Day 15 of the herb), subjects will return to the NIH where they will take their final LPV/r dose and then have their plasma collected for determination of lopinavir and ritonavir concentrations. On the last day (28th day) of herbal supplementation, participants will return to the NIH for determination of P-gp and 3A phenotypes using single doses of fexofenadine and midazolam as described for Study Day 1. Data from this investigation will determine whether echinacea, ginseng, or ginkgo biloba supplements alter the pharmacokinetics of the protease inhibitor combination lopinavir/ritonavir, and whether or not modulation of CYP3A and/or P-gp contributed to any observed interaction.
Ages Eligible for Study: | 18 Years to 50 Years |
Genders Eligible for Study: | Both |
Accepts Healthy Volunteers: | Yes |
INCLUSION CRITERIA:
EXCLUSION CRITERIA:
Concomitant routine therapy with any prescription, over-the-counter, herbal, or holistic medications, including oral contraceptives, for 30 days prior to study participation.
Contact: Patient Recruitment and Public Liaison Office | (800) 411-1222 | prpl@mail.cc.nih.gov |
Contact: Scott R. Penzak, Pharm.D. | (301) 496-2997 | spenzak@mail.cc.nih.gov |
United States, Maryland | |
National Institutes of Health Clinical Center, 9000 Rockville Pike | Recruiting |
Bethesda, Maryland, United States, 20892 |
Responsible Party: | National Institutes of Health ( Scott R. Penzak, Pharm.D./Warren G. Magnuson Clinical Center ) |
Study ID Numbers: | 050082, 05-CC-0082 |
Study First Received: | February 5, 2005 |
Last Updated: | October 24, 2008 |
ClinicalTrials.gov Identifier: | NCT00103012 |
Health Authority: | United States: Federal Government |
Antiretrovirals Protease Inhibitors Herbal Supplements Drug Interactions |
Metabolism Healthy Volunteer HV |
Lopinavir Ritonavir Fexofenadine Histamine phosphate |
Healthy Midazolam Histamine |
Anti-Infective Agents Neurotransmitter Agents HIV Protease Inhibitors Anti-HIV Agents Molecular Mechanisms of Pharmacological Action Physiological Effects of Drugs Histamine Agents Enzyme Inhibitors Anti-Allergic Agents |
Antiviral Agents Pharmacologic Actions Protease Inhibitors Histamine Antagonists Anti-Retroviral Agents Therapeutic Uses Histamine H1 Antagonists Histamine H1 Antagonists, Non-Sedating |