The Clinical and Economic Impact of Pharmacogenomic Testing of Warfarin Therapy in Typical Community Practice Settings

NCT ID: NCT00830570

Last Updated: 2010-11-16

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

1635 participants

Study Classification

OBSERVATIONAL

Study Start Date

2007-07-31

Study Completion Date

2010-01-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

The purpose of this quasi-experiment study, which could also be classified as a prospective observational intervention study, is to assess the impact of cytochrome P450 2C9 (CYP 2C9) and vitamin K epoxide reductase complex, subunit 1 (VKORC1) testing within a primary patient care setting.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Anticoagulation therapy with warfarin is the most common mode of treatment and prophylaxis for venous and arterial thromboembolic conditions. Warfarin is metabolized in the liver by the cytochrome P450 system, the cytochrome P450 2C9 (CYP 2C9) isoenzyme specifically, and polymorphisms in the CYP 2C9 gene have been associated with changes in metabolic function of the translated isoenzyme . These polymorphisms result in reduced metabolism of warfarin as compared to subjects having the wild type gene, consequently leading to systemic accumulation of warfarin; it is theorized that this leads to higher risk of adverse events. Other allelic variations have also been linked to changes in vitamin K conservation through their effects on vitamin K epoxide reductase complex, subunit 1 (VKORC1) . The combined impact of CYP 2C9 and VKORC1 polymorphisms on warfarin's pharmacology have recently been reported.

It is hypothesized that evaluation of genomic allelic type guided warfarin dosing will reduce thromboembolic and bleeding risks associated with warfarin therapy, and that adoption of a genetic testing strategy in a primary patient care setting would improve warfarin effectiveness and patient safety, and reduce costs to health care payers.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Embolism and Thrombosis Embolism Vascular Diseases Warfarin Venous Thromboembolism Thrombosis Thromboembolism

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

CYP2C9 VKORC1 polymorphism warfarin Coumadin

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

COHORT

Study Time Perspective

PROSPECTIVE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

1

Historical control group. Patients in this group are drawn from the same plan populations as the intervention group, but they are identified during the 1-year period prior to the start of patient enrollment in the intervention group. The historical control group is closely matched with the intervention group on demographic characteristics, practice patterns, and benefit plan features that may affect resource utilization.

No interventions assigned to this group

2

Concurrent control group. Patients in this group are drawn from different set of plan populations, but they initiate warfarin treatment during the same time period as patients in the intervention group. Outcomes data for the concurrent control group will be used to evaluate whether any differences between the intervention group and the historical control group can be attributed to changes in clinical practice over time. Baseline data for the concurrent control group will help validate the incidence assumptions used in the calculation of statistical power. This use of baseline population norms is an effective means of limiting bias in quasi-experimental studies.

No interventions assigned to this group

3

Active study group. For plans participating in the active arm of the study, enrollment is offered to every patient who initiates warfarin therapy during the enrollment period (beginning in July 2007) and who meets the eligibility criteria. Patients are identified for the active study group if they have a warfarin pharmacy claim and no prior warfarin claims during the preceding 180 days. Only patients who remain eligible for the pharmacy benefit throughout the study period are included in the final sample.

CYP 2C9 and VKORC1 Testing for Warfarin

Intervention Type OTHER

Test patients for their warfarin sensitivity and provide this information to their physician authorizing the test.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

CYP 2C9 and VKORC1 Testing for Warfarin

Test patients for their warfarin sensitivity and provide this information to their physician authorizing the test.

Intervention Type OTHER

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

Genetic testing for drug sensitivity

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Female and male age range of 40-75
* Patients who are in the induction phase of warfarin
* Patients receiving warfarin to prevent or treat thromboembolic conditions (e.g., post orthopedic surgery prophylaxis, deep venous thrombosis, atrial fibrillation, pulmonary embolism, heart failure)
* Patient willing to provide informed consent prior to the specimen collection procedure
* Patient whose physician is willing to order the genetic test

Exclusion Criteria

* Age \< 40 or \> 75
* Previous use of warfarin within 180 days of initiating new warfarin therapy
* Hospitalized for seven or more days before first claim for warfarin
* Previous history of genetic testing for warfarin therapy
* Known hypersensitivity to warfarin
* Patient or physician refusal to participate in the study
* Patients using warfarin residing in Olmsted County, MN
Minimum Eligible Age

40 Years

Maximum Eligible Age

75 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Mayo Clinic

OTHER

Sponsor Role collaborator

Washington University School of Medicine

OTHER

Sponsor Role collaborator

Medco Health Solutions, Inc.

INDUSTRY

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Medco Health Solutions, Inc.

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Robert Epstein, MD, MS

Role: PRINCIPAL_INVESTIGATOR

Medco Health Solutions, Inc.

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Medco Health Solutions, Inc.

Franklin Lakes, New Jersey, United States

Site Status

Countries

Review the countries where the study has at least one active or historical site.

United States

References

Explore related publications, articles, or registry entries linked to this study.

Epstein RS, Moyer TP, Aubert RE, O Kane DJ, Xia F, Verbrugge RR, Gage BF, Teagarden JR. Warfarin genotyping reduces hospitalization rates results from the MM-WES (Medco-Mayo Warfarin Effectiveness study). J Am Coll Cardiol. 2010 Jun 22;55(25):2804-12. doi: 10.1016/j.jacc.2010.03.009. Epub 2010 Apr 8.

Reference Type RESULT
PMID: 20381283 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

MedcoWarfarin1

Identifier Type: -

Identifier Source: org_study_id