Clarification of Optimal Anticoagulation Through Genetics — COAG  

Stroke Clinical Trial

Official title: A Randomized, Multi-Center, Double-Blind Clinical Trial to Evaluate the Use of Clinical Plus Genetic Information to Guide Warfarin Therapy Initiation and Improve Anticoagulation Control for Patients

Status Completed

Clinical Trial Summary

Individuals taking warfarin often need frequent dose changes as the international normalized ratio (INR) gets too high or too low which could result in a higher risk of thromboembolism, bleeding and early discontinuation of a highly useful therapy. This study will compare two approaches to warfarin dosing to examine the utility of using genetic information for warfarin dosing.

Clinical Trial Description

The objective of the Clarification of Optimal Anticoagulation through Genetics (COAG) trial is to conduct a 1,022 participant, multicenter, double-blind, randomized trial comparing two approaches to guiding warfarin therapy initiation: 1) initiation of warfarin therapy based on algorithms using clinical information and an individual's genotype using genes known to influence warfarin response ("genotype-guided dosing"), and 2) initiation of warfarin therapy based on algorithms using only clinical information ("clinical-guided dosing"). The study hypothesis is that the use of genetic and clinical information for selecting the dose of warfarin during the initial dosing period will lead to improvement in stability of anticoagulation(AC) relative to a strategy that incorporates only clinical information (without genetics) for initial dosing. Each study arm will include a baseline dose initiation algorithm and a dose revision algorithm applied over the first 4 to 5 doses of warfarin therapy. By comparing the two strategies in this trial, the study will be able to determine if genetic information provides added benefit above and beyond what can be gleaned simply with clinical information. This study is a proof-of-concept efficacy trial. Efficacy is defined as a measure of whether, under optimal application, dosing algorithms will lead to improvement in care. The trial will thus answer the question: "can the use of clinical plus genetic information lead to an improvement in anticoagulation control above and beyond the use of only clinical information during the initiation of warfarin, when applied in a uniform and optimal manner to all patients?" Because efficacy has not yet been established for genotype-guided dosing of warfarin, it is important to first test whether this approach can, indeed, improve anticoagulation outcomes under controlled conditions. ;

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Atrial Fibrillation
• Atrial Flutter
• Stroke
• Thrombosis
• Venous Thrombosis

• NCT number: NCT00839657
• Study type: Interventional
• Source: National Heart, Lung, and Blood Institute (NHLBI)
• Status: Completed
• Phase: Phase 3
• Start date: September 2009
• Completion date: November 2013