Study of Genetic Factors Other Than CYP2C9 and VKORC1 That Influence Warfarin Dose Requirements in a South-east Asian Population

• Conditions: Cancer
• Interventions: Biological: Blood collection

• Registration Number: NCT01050920
• Lead Sponsor: National University Hospital, Singapore

Brief Summary

Warfarin is a commonly used anti-coagulant, but has a narrow therapeutic index and wide inter-individual and inter-ethnic variation in dose requirements. Several genetic and non-genetic factors have been identified that could influence warfarin dose requirements. However, current known predictive factors could only explain about 50-60% of warfarin dose variability. Inter-ethnic differences in genetic influences on warfarin dose requirements also exist. We hypothesize that genetic factors other than CYP2C9 and VKORC1 may influence warfarin dosing and serve to further optimize warfarin dosing.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2010-01-15
• Study First Submitted QC: 2010-01-15
• Study First Posted: 2010-01-18
• Study Start: 2013-09
• Status Verified: 2014-01
• Last Update Submitted: 2014-01-21
• Last Update Posted: 2014-01-22
• Primary Completion: 2014-12
• Study Completion: 2014-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: Not specified

Inclusion Criteria

• patients receiving maintenance warfarin therapy with a stable therapeutic international normalized ratio (INR) between 2 and 3 for at least 3 months,
• patients recruited from the anticoagulation clinics at the National University Hospital and Tan Tock Seng Hospital in Singapore between June 2002 and June 2004 for a previous genotyping study (C/00/510, NUH; C/00/535, TTSH, PI-Dr Goh Boon Cher).

Exclusion Criteria

• patients below 21 years old, or
• patients with liver disease, malabsorption or chronic diarrheal diseases, or
• patients taking drugs that may potentially interact with warfarin.

Dietary advice to avoid foods that may interfere with warfarin pharmacokinetics will be given to patients during warfarin therapy.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Blood Collection	Blood collection	-

Primary Outcome Measures

Name	Time	Method
To identify genetic variants other than CYP2C9 and VKORC1 that may influence warfarin dose requirements in a multi-ethnic population in Singapore.

Trial Locations

Locations (1)

National University Hospital; 🇸🇬 Singapore, Singapore