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Clarification of Optimal Anticoagulation Through Genetics (COAG)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT00839657
Recruitment Status : Completed
First Posted : February 9, 2009
Last Update Posted : April 20, 2016
Sponsor:
Collaborator:
Bristol-Myers Squibb
Information provided by (Responsible Party):
National Heart, Lung, and Blood Institute (NHLBI)

Brief 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.

Condition or disease Intervention/treatment Phase
Stroke Venous Thrombosis Atrial Fibrillation Atrial Flutter Behavioral: Genotype-guided dosing algorithm for warfarin Behavioral: Clinical-guided dosing algorithm for warfarin Phase 3

Detailed 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.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 1015 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
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
Study Start Date : September 2009
Actual Primary Completion Date : April 2013
Actual Study Completion Date : November 2013

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Blood Thinners

Arm Intervention/treatment
Experimental: 1
Genotype-guided dosing algorithm for warfarin
Behavioral: Genotype-guided dosing algorithm for warfarin
Initial dosing of warfarin for the first 3-4 days of treatment will be determined by an algorithm that uses clinical and genetic information. Following this initiation dose of warfarin, a second dose adjustment will be made after 3 and/or 4 doses of warfarin using a dose revision algorithm that incorporates the clinical and genetic information.

Active Comparator: 2
Clinical-guided dosing algorithm for warfarin
Behavioral: Clinical-guided dosing algorithm for warfarin
Initial dosing of warfarin for the first 3-4 days of treatment will be determined by an algorithm that uses clinical information. Following this initiation dose of warfarin, a second dose adjustment will be made after 3 and/or 4 doses of warfarin using a dose revision algorithm that incorporates the clinical information.




Primary Outcome Measures :
  1. Percentage of time participants spend within the therapeutic INR range (PTTR) [ Time Frame: Measured during the first 4 weeks of therapy ]

Secondary Outcome Measures :
  1. Occurrence of INR greater than 4 or serious clinical event [ Time Frame: Measured during the first 4 weeks ]


Information from the National Library of Medicine

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, Learn About Clinical Studies.


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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Willingness and ability to sign informed consent
  • Able to be followed in outpatient AC clinic
  • Expected duration of warfarin therapy of at least 1 month
  • AC management for the patient will be performed in-hospital and as an outpatient by clinicians that will adhere to the study dosing algorithms and dose titration plans
  • Target INR 2-3

Exclusion Criteria:

  • Currently taking warfarin
  • Prior warfarin therapy with known required stable dose
  • Clinician opinion that warfarin dosing needs to be adjusted for reasons not accounted for by dosing algorithm
  • Abnormal baseline INR (off warfarin) (e.g., due to liver disease, antiphospholipid antibody)
  • Contraindication to warfarin treatment for at least 3 months
  • Life expectancy of less than 1 year
  • Pregnant women or child-bearing women not using medically approved method of birth control (requires negative pregnancy test to exclude pregnancy in child-bearing women)
  • Inability to follow-up on a regular basis with anticoagulation practitioners participating in the trial
  • Any factors likely to limit adherence to warfarin
  • Cognitive or other causes of inability to provide informed consent or follow study procedures
  • Participating in another trial that prohibits participation in the COAG trial or planned enrollment in such a trial within the first 6 months of warfarin therapy
  • Estimated blood loss of more than 1,000 cc requiring blood transfusions within 48 hours prior to randomization
  • Genotype (CYP2C9 or VKORC1) known to participant from prior testing

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00839657


Locations
Show Show 18 study locations
Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Bristol-Myers Squibb
Investigators
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Principal Investigator: Stephen E Kimmel, MD, MSCE University of Pennsylvania
Study Data/Documents: Individual Participant Data Set  This link exits the ClinicalTrials.gov site
Identifier: COAG
NHLBI provides controlled access to IPD through BioLINCC. Access requires registration, evidence of local IRB approval or certification of exemption from IRB review, and completion of a data use agreement.

Publications of Results:
Other Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: National Heart, Lung, and Blood Institute (NHLBI)
ClinicalTrials.gov Identifier: NCT00839657    
Other Study ID Numbers: 623
N01 HV88210
HHSN268200800003C
First Posted: February 9, 2009    Key Record Dates
Last Update Posted: April 20, 2016
Last Verified: May 2013
Keywords provided by National Heart, Lung, and Blood Institute (NHLBI):
Embolism
Thrombosis
Additional relevant MeSH terms:
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Atrial Fibrillation
Thrombosis
Venous Thrombosis
Atrial Flutter
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Embolism and Thrombosis
Vascular Diseases
Warfarin
Anticoagulants