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

Venous Thromboembolism Clinical Trial

— MHSMayoWarf1  

Official title:

in Typical Community Practice Settings

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00830570
• Other study ID #: MedcoWarfarin1
• Status: Completed
• Phase: N/A
• First received: January 26, 2009
• Last updated: November 15, 2010
• Start date: July 2007
• Est. completion date: January 2010

Study information

• Verified date: November 2010
• Source: Medco Health Solutions, Inc.
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

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.

Description:

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 1635
• Est. completion date: January 2010
• Est. primary completion date: January 2010
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 40 Years to 75 Years

Eligibility

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

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Embolism
• Embolism and Thrombosis
• Thromboembolism
• Thrombosis
• Vascular Diseases
• Venous Thromboembolism
• Warfarin

Intervention

Other:
• CYP 2C9 and VKORC1 Testing for Warfarin
Test patients for their warfarin sensitivity and provide this information to their physician authorizing the test.

Locations

Country	Name	City	State
United States	Medco Health Solutions, Inc.	Franklin Lakes	New Jersey

Sponsors (3)

Lead Sponsor	Collaborator
Medco Health Solutions, Inc.	Mayo Clinic, Washington University School of Medicine

Country where clinical trial is conducted

United States, 

References & Publications (1)

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 — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The primary objective of the study is to determine whether the addition of genotyping to usual care will reduce the hospitalization rates for hemorrhage or thromboembolism related to warfarin use during the first 6 months of treatment.		6 months	No
Secondary	The secondary objective is to determine physician and patient acceptance of the technology.		6 months	No