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Pharmacogenetic Study of Warfarin Dose-Response: a Prospective Trial (PGxWarfarin)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified April 2008 by Sheba Medical Center.
Recruitment status was:  Not yet recruiting
Information provided by:
Sheba Medical Center Identifier:
First received: April 4, 2008
Last updated: NA
Last verified: April 2008
History: No changes posted

We propose to develop a personalized pharmacogenetic approach including the major genetic markers of warfarin (coumadin) dosing and patients' age and weight. The known genetic determinants include several functional and common polymorphisms in CYP2C9 and VKORC1 genes, which explain the low-end of warfarin dosing range and mostly occur in patients of Caucasian and Chinese origins. We identified a new VKORC1 polymorphism that is specifically indicative of the high dose requirements and is dominant over the dose-reducing effect of the known CYP2C9 and VKORC1 markers. This marker is significantly over-represented in Jews of Ethiopian origin, but is also common in Ashkenazis, it is also linked to the VKORC1 genetic markers characteristic of the Afro-American population (published in Blood 2007, 109:2477-80). This information prompts the development of a more inclusive and universal diagnostic approach to the individualized warfarin therapy.

The present study aims at evaluation of our novel pharmacogenetic model for predicting warfarin (coumadin) dose response on the basis of patient's genetic markers of warfarin sensitivity and resistance, and other patient specific factors. To this end, we proposes to re-evaluate our previously developed pharmacogenetic model in stabilized warfarin treated patients (N=200) and then to implement it in a prospective study of patients new on warfarin as compared to the "traditionally" treated patients (N=500).

Cardiovascular Diseases

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Prospective Study Comparing Between the Commonly-Used and Pharmacogenetically-Guided Warfarin Administration Protocols

Resource links provided by NLM:

Further study details as provided by Sheba Medical Center:

Biospecimen Retention:   Samples With DNA
Whole blood

Estimated Enrollment: 500
Study Start Date: June 2008
Estimated Study Completion Date: June 2011
Estimated Primary Completion Date: June 2010 (Final data collection date for primary outcome measure)
  Show Detailed Description


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
community sample

Inclusion Criteria:

  • patients starting warfarin therapy

Exclusion Criteria:

  • pregnant women
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00654823

Institute of Clinical Pharmacology Not yet recruiting
Tel Hashomer, Israel, 52621
Contact: Eva Gak, PhD    972-3-530-3946   
Principal Investigator: Ronen Loebstein, MD         
Sponsors and Collaborators
Sheba Medical Center
Principal Investigator: Ronen Loebstein, MD Sheba Medical Center
  More Information

Responsible Party: Dr. Ronen Loebstein, Sheba Medical Center Identifier: NCT00654823     History of Changes
Other Study ID Numbers: SHEBA-XX-XXXX-EG-CTIL
Study First Received: April 4, 2008
Last Updated: April 4, 2008

Additional relevant MeSH terms:
Cardiovascular Diseases
Anticoagulants processed this record on August 17, 2017