The Interaction of Herbs and Statins

September 30, 2021 updated by: Brian Tomlinson, Chinese University of Hong Kong

Interactions of Herbs With Statin Drugs and Potential Mediation by Drug Transporters

This project includes two separate pharmacokinetic studies with simvastatin and rosuvastatin, respectively. Each study is an open-label, single-dose, randomized, three-phase (no herbs, with green tea, with soy isoflavones) clinical pharmacokinetic study design with a wash-out of at least 4-weeks between phases. The aim is to examine whether green tea extract and soy isoflavones affect the pharmacokinetics of simvastatin and rosuvastatin in healthy subjects and whether these interactions are influenced by polymorphisms in the relevant drug transporters, solute carrier 1B1 (SLCO1B1) and adenosine triphosphate (ATP) binding cassette G2 (ABCG2) and to identify whether polymorphisms in drug transporters influence the pharmacokinetics of simvastatin and rosuvastatin. After informed consent is obtained, subjects are required to abstain from any prescription or non-prescription medications 2 weeks before and throughout the study. Subjects are given a single dose of simvastatin 20 mg (Zocor®, MSD) or rosuvastatin 10 mg (Crestor®, Astra Zeneca) on 3 occasions: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract. The green tea extract and soy isoflavones extract are given at a dose containing epigallocatechin gallate (EGCG) 800 mg once daily or isoflavones 120 mg once daily for 14 days before statin dosing with at least 4-week washout period between phases. Blood samples are taken at intervals from 0 to 24 hours on the statin dosing days. During the study, subjects are reminded frequently of the requirements on diet.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Healthy Chinese male subjects aged 18-45 years are recruited from a pool of over 200 healthy volunteers who had been genotyped for the SLCO1B1 388A>G, 521T>C and ABCG2 421C>A polymorphisms. All subjects are required to abstain from any prescription or non-prescription medications 2 weeks before and throughout the study. They are not allowed to take alcohol, tea, grapefruit juice, caffeine, soybean milk or dietary supplements and herbal products 2 weeks before and throughout the entire study period. They are also not allowed to smoke 2 weeks before and throughout the study. Subjects are requested to fast for 10 h before and 4 h after drug administration during the blood sampling sessions. Meals are standardized and consumed at 4 h and 10 h post dosing. Drinking water are not allowed from 1 h pre-dose to 1 h post-dose except that needed for drug dosing at the time of blood sampling sessions. Subjects are given a single dose of simvastatin 20 mg (Zocor®, MSD) or rosuvastatin 10 mg (Crestor®, Astra Zeneca) on 3 occasions: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract. The green tea extract and soy isoflavones extract are given at a dose containing EGCG 800 mg once daily or isoflavones 120 mg once daily for 14 days before statin dosing with at least 4-week washout period between phases.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
38

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Hong Kong
      • Hong Kong, Hong Kong
        • Chinese University of Hong Kong

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 45 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

Inclusion Criteria:

  • Healthy Chinese male subjects aged 18 - 45 years
  • healthy volunteers who had been genotyped for the SLCO1B1 388A>G, 521T>C and ABCG2 421C>A polymorphisms.

Exclusion Criteria:

  • Female
  • Patients with any disease
  • Volunteers who cannot follow the instructions
  • Volunteers who don't sign the informed consent.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Sequential Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Other: simvastatin 20 mg (Zocor®, MSD)
simvastatin 20 mg are given on 3 occasions: 1. without herbs; 2. with green tea extract containing EGCG 800 mg once daily for 14 days before statin dosing; 3. with soy isoflavones extract containing isoflavones 120 mg once daily for 14 days before statin dosing, with at least 4-week washout period between phases.
Drug: Simvastatin 20 mg (Zocor®, MSD)
Simvastatin 20 mg given once alone, once with green tea extract and once with soy isoflavones extract.
Other Names:
  • Green tea extract
  • Soy isoflavones extract
Other: rosuvastatin 10 mg (Crestor®, Astra Zeneca)
rosuvastatin 10 mg are given on 3 occasions: 1. without herbs; 2. with green tea extract containing EGCG 800 mg once daily for 14 days before statin dosing; 3. with soy isoflavones extract containing isoflavones 120 mg once daily for 14 days before statin dosing, with at least 4-week washout period between phases
Drug: rosuvastatin 10 mg (Crestor®, Astra Zeneca)
rosuvastatin 10 mg are given once alone, once with green tea extract and once with soy isoflavones extract.
Other Names:
  • Green tea extract
  • Soy isoflavones extract

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
The interactions of green tea extract and soy isoflavones on the maximum plasma concentration of simvastatin
Time Frame: 14 weeks
Maximum plasma concentration for simvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract.
14 weeks
The interactions of green tea extract and soy isoflavones on the area under plasma concentration-time curve of simvastatin
Time Frame: 14 weeks
Area under plasma concentration-time curve for simvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract.
14 weeks
The interactions of green tea extract and soy isoflavones on the maximum plasma concentration of rosuvastatin
Time Frame: 14 weeks
Maximum plasma concentration for rosuvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract.
14 weeks
The interactions of green tea extract and soy isoflavones on the area under plasma concentration-time curve of rosuvastatin
Time Frame: 14 weeks
Area under plasma concentration-time curve for rosuvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract.
14 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
The influence of polymorphisms in drug transporters on the maximum plasma concentration of simvastatin and the interaction with herbs.
Time Frame: 14 weeks
Maximum plasma concentration for simvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract with subjects divided according to genotypes of drug transporters.
14 weeks
The influence of polymorphisms in drug transporters on the area under plasma concentration-time curve of simvastatin and the interaction with herbs.
Time Frame: 14 weeks
Area under plasma concentration-time curve for simvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract with subjects divided according to genotypes of drug transporters.
14 weeks
The influence of polymorphisms in drug transporters on the maximum plasma concentration of rosuvastatin and the interaction with herbs.
Time Frame: 14 weeks
Maximum plasma concentration for rosuvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract with subjects divided according to genotypes of drug transporters.
14 weeks
The influence of polymorphisms in drug transporters on the area under plasma concentration-time curve of rosuvastatin and the interaction with herbs.
Time Frame: 14 weeks
Area under plasma concentration-time curve for rosuvastatin comparing: 1. without herbs; 2. with green tea extract; 3. with soy isoflavones extract with subjects divided according to genotypes of drug transporters.
14 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Chinese University of Hong Kong

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 11, 2013

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 30, 2013

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 28, 2021

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 29, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 30, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 8, 2021

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
October 8, 2021

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 30, 2021

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2021

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • herbals

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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