The response to warfarin varies greatly among individuals. Some of this variability can be ascribed to genetic polymorphisms in the gene encoding for CYP2C9, the enzyme mediating the metabolism of S warfarin. The present study has several segments:

1. Evaluation of the relationship between CYP2C9 genetic polymorphisms warfarin maintenance dose at steady state (completed). This study is a confirmation of previous data in our own population.
2. Testing the hypothesis that warfarin loading based on the individual''''s CYP2C9 genotype may be more efficient and associated with reduced adverse drug effects.

Condition	Intervention
Venous Thrombosis Pulmonary Embolism Atrial Fibrillation	Drug: Warfarin

Further Study Details: 

Primary Outcomes: Pharmacokinetic end points:; 1. Warfarin clearance and formation clearance of 7-hydroxy-warfarin at steady state; Pharmacodynamic; 1. Maintenance dose of warfarin at steady state; 2. Time to reach INR > 2; 3. Time to reach pharmacodynamic steady state; 4. Time spent at therapeutic INR <3 and >2.; 5. Time spent at INR >3; 6. Time spent at INR <2; 7. The incidence of minor and major bleeding episodes
Expected Total Enrollment:  400

Ages Eligible for Study:  18 Years and above,  Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• Patients in whom warfarin is about to be initiated
• Desired therapeutic range >2 and <3

Exclusion Criteria:

• Refusal to participate in the study

Please refer to this study by ClinicalTrials.gov identifier  NCT00162435

Yoseph Caraco, MD      00 972 2 6778584    caraco@hadassah.org.il

Israel
      Hadassah Medical Organization, Jerusalem,  Israel; Recruiting

Study chairs or principal investigators

Yoseph Caraco, MD,  Principal Investigator,  Hadassah Medical Organization   

Study ID Numbers:  22-15/06/01
Last Updated:  September 12, 2005
Record first received:  September 11, 2005
ClinicalTrials.gov Identifier:  NCT00162435
Health Authority: Israel: Israeli Health Ministry Pharmaceutical Administration
ClinicalTrials.gov processed this record on 2005-09-13