Human Cytochrome P450 4F Enzymes and Drug Interactions

January 17, 2013 updated by: Kim Brouwer, PharmD, PhD, University of North Carolina, Chapel Hill
Drug-drug interactions play an important role in clinical adverse events due to the prevalence of multi-drug therapy. Co-administration of warfarin and a statin has expanded substantially in the US over the last decades. The purpose of this study is to develop a mechanistic understanding of the role of a drug-metabolizing enzyme, CYP4F2, in the interaction between warfarin and statins. This study will test the hypothesis that lovastatin potentiates the anticoagulant effect of warfarin by inducing vitamin K-metabolizing enzyme CYP4F2 in humans, thus increasing warfarin's anticoagulant effect.

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.

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.
19

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 1

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

  • United States
    • North Carolina
      • Chapel Hill, North Carolina, United States, 27599
        • University of North Carolina, Clinical and Translational Research Center (CTRC)

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 60 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Normal baseline clinical laboratory results including coagulation panel (prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (APTT)), liver function tests (ALT, AST, alkaline phosphatase and total bilirubin), kidney function tests (serum creatinine and BUN), lipid panel (cholesterol, LDL-C, HDL-C, and triglycerides), and blood creatine kinase
  • Minimum weight of 110 lbs and minimum hemoglobin level at 12.5 g/dL
  • Ability to understand the informed consent form
  • Willing to abstain from grapefruit products, alcohol, and physical contact sports

Exclusion Criteria:

  • History of intolerance, allergy, or hypersensitivity to study drugs warfarin and lovastatin or any substances contained in the medication
  • History of clotting disorders, stroke, hypertension, anemia, renal insufficiency, hepatic dysfunction, platelet dysfunction, gastrointestinal bleeding, or any recent bleeding episode or trauma within 6 months
  • History of significant medical conditions that the study physician believes would increase risk (e.g., additional bleeding disorders)
  • Genotype non-homozygous for CYP2C9*1 or genotype VKORC1-1639AA
  • History of significant alcohol abuse and/or illicit drug use
  • Tobacco use within the month preceding the study
  • Woman who is pregnant or breastfeeding
  • Women who are unable to maintain adequate birth control during the study
  • Post-menopausal women on estrogen replacement
  • Chronic statin or warfarin use
  • Taking concomitant medications, both prescription and non-prescription (including herbal products, over-the-counter medications, and multivitamins), known to alter lovastatin, warfarin, or vitamin K blood levels (women stabilized on hormonal methods of birth control will be allowed to participate, and subjects stabilized on antidepressant medications will be allowed to participate)
  • Recent use of antibacterial antibiotics
  • Recent blood donation or participation in other clinical studies within past 8 weeks

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: Crossover Assignment
  • Masking: Triple

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.
Experimental: Warfarin plus lovastatin
Drug: Warfarin
10 mg, po, single dose on day 7
Other Names:
  • Coumadin
Drug: Lovastatin
40 mg, po, once a day, days 1 through 14
Other Names:
  • Mevacor
Placebo Comparator: Warfarin plus placebo
Drug: Warfarin
10 mg, po, single dose on day 7
Other Names:
  • Coumadin
Drug: Placebo
po, once a day, days 1 through 14

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
Pharmacodynamics
Time Frame: Measurement will be performed before (baseline) and 2, 4, 8, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168h after co-administration of warfarin and lovastatin/placebo and during screening.
Measurement of Prothrombin time (PT) to assess the International Normalized Ratio (INR).
Measurement will be performed before (baseline) and 2, 4, 8, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168h after co-administration of warfarin and lovastatin/placebo and during screening.

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
Pharmacokinetics
Time Frame: Sampling will be performed before and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168 h after co-administration of warfarin and lovastatin/placebo.
Vitamin K1 and vitamin K1 metabolite measured by maximum plasma concentration and AUC.
Sampling will be performed before and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168 h after co-administration of warfarin and lovastatin/placebo.
Pharmacokinetics
Time Frame: Sampling will be performed before and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168 h after co-administration of warfarin and lovastatin/placebo.
Pharmacokinetics for (R)- and (S)- Warfarin, and lovastatin measured by maximum plasma concentration and AUC.
Sampling will be performed before and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48, 60, 72, 96, 120, 144, and 168 h after co-administration of warfarin and lovastatin/placebo.

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.
University of North Carolina, Chapel Hill

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institutes of Health (NIH)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Director: Michael Z Wang, PhD, University of Kansas
  • Principal Investigator: Kim LR Brouwer, PharmD PhD, University of North Carolina, Chapel Hill

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

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.
December 1, 2010

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 1, 2011

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.
December 1, 2011

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).
November 29, 2010

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.
November 29, 2010

First Posted (Estimate)

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.
November 30, 2010

Study Record Updates

Last Update Posted (Estimate)

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.
January 21, 2013

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.
January 17, 2013

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.
January 1, 2013

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.
  • 10-0576
  • 1R01GM089994-01A1 (U.S. NIH Grant/Contract)

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.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings