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EUropean Pharmacogenetics of AntiCoagulant Therapy - Warfarin (EU-PACT)

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT01119300
First Posted: May 7, 2010
Last Update Posted: December 3, 2014
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.
Collaborators:
Utrecht University
Leiden University Medical Center
Erasmus Medical Center
University of Ulm
Newcastle University
University of Liverpool
LGC Limited
Uppsala University
Democritus University of Thrace
Elisabethinen Hospital
Information provided by (Responsible Party):
Anke-Hilse Maitland-van der Zee, Utrecht Institute for Pharmaceutical Sciences
  Purpose

Rationale:

The narrow therapeutic range and wide inter-patient variability in dose requirement make anticoagulation response to coumarin derivatives unpredictable. As a result, patients require frequent monitoring to avert adverse effects and maintain therapeutic efficacy. Polymorphisms in cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex 1 (VKORC1) jointly account for about 40% of the inter-individual variability in dose requirements. To date, several pharmacogenetic guided dosing algorithms for coumarin derivatives, predominately for warfarin, have been developed. However, the potential benefit of these dosing algorithms in terms of their safety and clinical utility has not been adequately investigated in randomised settings. Objective:

To determine whether a dosing algorithm containing genetic information increases the time within therapeutic INR range during anticoagulation therapy with each of warfarin, acenocoumarol and phenprocoumon compared to a dosing regimen that does not contain this information. Secondary outcomes of the study include cost effectiveness, number of thromboembolic and bleeding events, time to reach stable dose and number of supratherapeutic INR peaks.


Condition Intervention Phase
Venous Thromboembolism Atrial Fibrillation Other: Genotype-guided dosing algorithm Other: Standard care Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Official Title: EUropean Pharmacogenetics of AntiCoagulant Therapy - Warfarin

Resource links provided by NLM:


Further study details as provided by Anke-Hilse Maitland-van der Zee, Utrecht Institute for Pharmaceutical Sciences:

Primary Outcome Measures:
  • Percent time within therapeutic INR range 2-3 during 12 weeks following the initiation of coumarin therapy [ Time Frame: 12 weeks ]

Secondary Outcome Measures:
  • Time INR > or = 4.0, which indicates overanticoagulation [ Time Frame: 12 weeks ]
  • Percent time spent > or = INR 4.0 [ Time Frame: 12 weeks ]
  • Percent time spent < or = INR 2, which indicates under-anticoagulation [ Time Frame: 12 weeks ]
  • Time to reach therapeutic INR defined as the time to the first INR within target range, providing that a subsequent INR > or =1 week later is also within target range [ Time Frame: 12 weeks ]
  • Time to reach stable dose defined as INR within target range for a period of at least 3 weeks with <10% change in dose [ Time Frame: 12 weeks ]
  • Time to and number of minor and major bleeding events [ Time Frame: 12 weeks ]
  • Time to and number of thromboembolic events (therapeutic failure) [ Time Frame: 12 weeks ]
  • The incidence of coumarin sensitivity [ Time Frame: 12 weeks ]
  • The incidence of coumarin resistance [ Time Frame: 12 weeks ]
  • Number of coumarin dose adjustments [ Time Frame: 12 weeks ]
  • The clinical utility of the rapid genotyping test developed by LGC [ Time Frame: 2 years ]
  • Quality of life as reported by the patient tested by the EuroQol (EQ)-5D questionnaire [ Time Frame: 12 weeks ]
  • The cost-effectiveness of genotype-guided dosing for each coumarin compared with non-genotype-guided dosing [ Time Frame: will be assessed after inclusion of all patients ]
  • Number of patients with INR > or = 4.0, which indicates overanticoagulation [ Time Frame: 12 weeks ]

Enrollment: 455
Study Start Date: January 2011
Study Completion Date: October 2013
Primary Completion Date: October 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Standard care
Standard care
Other: Standard care
Standard care
Experimental: Genotype-guided dosing algorithm
Genotyping for CYP2C9*2, CYP2C9*3, and VKORC1 (-1639G→A) was performed with the use of a point-of-care test. For patients assigned to the genotype-guided group, warfarin doses were prescribed according to pharmacogenetic-based algorithms for the first 5 days.
Other: Genotype-guided dosing algorithm
Loading and monitoring dose according to genotype-guided dosing algorithm

Detailed Description:
Study design: This is a two-armed, single-blinded, randomised controlled trial. In one arm (intervention) patients commencing anticoagulation therapy with either warfarin, acenocoumarol or phenprocoumon will be dosed according to a drug-specific genotype-guided dosing algorithm, which is based on genetic information, clinical data and (in the monitoring phase) previous INR. For the other arm (control) patients will be dosed according to a non-genotype-guided dosing regimen which does not include genetic information. The follow-up period per patient is 3 months. Study population: Newly diagnosed patients of both genders and at least 18 years old who need anticoagulant treatment with either acenocoumarol, phenprocoumon or warfarin within the low intensity INR range will be included in the trial. Main study parameters/endpoints: The % time within therapeutic INR range in the first 3 months of anticoagulation therapy. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Six extra blood samples are taken from each participant at the start of the study. Patients also have to attend 8 scheduled visits within the 3 months study period and are asked to fill in questionnaires. The genotype-guided dosing algorithm is anticipated to improve the accuracy of coumarin dosing and thus improve the safety and efficacy of anticoagulation therapy.
  Eligibility

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.


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

Inclusion Criteria:

  • Patients with either venous thromboembolism (VTE) or atrial fibrillation (AF) requiring coumarin therapy for at least 12 weeks and a target INR in the low intensity range (INR range 2-3 in the United Kingdom, Sweden, Germany, Austria and Greece and INR 2.5-3.5 in the Netherlands)
  • Age ≥ 18 years
  • Ability to attend scheduled visits
  • Signed informed consent

Exclusion Criteria:

  • Presence of a mechanical heart valve
  • Severe cognitive impairment
  • Known genotype CYP2C9 or VKORC1 at start of the study
  • Previous or current treatment with any coumarin
  • Pregnancy or lactation
  • Non-eligible subject
  Contacts and Locations
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): NCT01119300


Locations
Sweden
Uppsala University
Uppsala, Sweden
United Kingdom
University of Liverpool
Liverpool, United Kingdom
University of Newcastle
Newcastle, United Kingdom
Sponsors and Collaborators
Utrecht Institute for Pharmaceutical Sciences
Utrecht University
Leiden University Medical Center
Erasmus Medical Center
University of Ulm
Newcastle University
University of Liverpool
LGC Limited
Uppsala University
Democritus University of Thrace
Elisabethinen Hospital
Investigators
Principal Investigator: Munir Pirmohamed, MD PhD University of Liverpool
  More Information

Publications:
Pirmohamed M, Burnside G, Eriksson N, Jorgensen AL, Toh CH, Nicholson T, Kesteven P, Christersson C, Wahlström B, Stafberg C, Zhang JE, Leathart JB, Kohnke H, Maitland-van der Zee AH, Williamson PR, Daly AK, Avery P, Kamali F, Wadelius M; EU-PACT Group. A randomized trial of genotype-guided dosing of warfarin. N Engl J Med. 2013 Dec 12;369(24):2294-303. doi: 10.1056/NEJMoa1311386. Epub 2013 Nov 19.
van Schie RM, Wadelius MI, Kamali F, Daly AK, Manolopoulos VG, de Boer A, Barallon R, Verhoef TI, Kirchheiner J, Haschke-Becher E, Briz M, Rosendaal FR, Redekop WK, Pirmohamed M, Maitland van der Zee AH. Genotype-guided dosing of coumarin derivatives: the European pharmacogenetics of anticoagulant therapy (EU-PACT) trial design. Pharmacogenomics. 2009 Oct;10(10):1687-95. doi: 10.2217/pgs.09.125.
Verhoef TI, Redekop WK, Darba J, Geitona M, Hughes DA, Siebert U, de Boer A, Maitland-van der Zee AH, Barallon R, Briz M, Daly A, Haschke-Becher E, Kamali F, Kirchheiner J, Manolopoulos VG, Pirmohamed M, Rosendaal FR, van Schie RM, Wadelius M; EU-PACT Group. A systematic review of cost-effectiveness analyses of pharmacogenetic-guided dosing in treatment with coumarin derivatives. Pharmacogenomics. 2010 Jul;11(7):989-1002. doi: 10.2217/pgs.10.74. Review.
van Schie RM, Jorgensen AL, de Boer A, Maitland-van der Zee AH; EU-PACT study group. Systematic review of pharmacogenetic warfarin dosing. J Gen Intern Med. 2009 Oct;24(10):1171. doi: 10.1007/s11606-009-1083-9.
van Schie RM, Verhoef TI, Boejharat SB, Schalekamp T, Wessels JA, le Cessie S, Rosendaal FR, van der Meer FJ, de Boer A, Maitland-van der Zee AH. Evaluation of the effect of statin use on the acenocoumarol and phenprocoumon maintenance dose. Drug Metabol Drug Interact. 2012;27(4):229-34.
Verhoef TI, Redekop WK, Hegazy H, de Boer A, Maitland-van der Zee AH; EU-PACT group. Long-term anticoagulant effects of CYP2C9 and VKORC1 genotypes in phenprocoumon users. J Thromb Haemost. 2012 Dec;10(12):2610-2. doi: 10.1111/jth.12007.
Verhoef TI, Redekop WK, van Schie RM, Bayat S, Daly AK, Geitona M, Haschke-Becher E, Hughes DA, Kamali F, Levin LÅ, Manolopoulos VG, Pirmohamed M, Siebert U, Stingl JC, Wadelius M, de Boer A, Maitland-van der Zee AH; EU-PACT group. Cost-effectiveness of pharmacogenetics in anticoagulation: international differences in healthcare systems and costs. Pharmacogenomics. 2012 Sep;13(12):1405-17. Review.
van Schie RM, el Khedr N, Verhoef TI, Teichert M, Stricker BH, Hofman A, Buhre PN, Wessels JA, Schalekamp T, le Cessie S, van der Meer FJ, Rosendaal FR, de Boer A, Maitland-van der Zee AH, Visser LE. Validation of the acenocoumarol EU-PACT algorithms: similar performance in the Rotterdam Study cohort as in the original study. Pharmacogenomics. 2012 Aug;13(11):1239-45. doi: 10.2217/pgs.12.101.
van Schie RM, Babajeff AM, Schalekamp T, Wessels JA, le Cessie S, de Boer A, van der Meer FJ, van Meegen E, Verhoef TI, Rosendaal FR, Maitland-van der Zee AH; EU-PACT study group. An evaluation of gene-gene interaction between the CYP2C9 and VKORC1 genotypes affecting the anticoagulant effect of phenprocoumon and acenocoumarol. J Thromb Haemost. 2012 May;10(5):767-72. doi: 10.1111/j.1538-7836.2012.04694.x.
Verhoef TI, Redekop WK, Buikema MM, Schalekamp T, Van Der Meer FJ, Le Cessie S, Wessels JA, Van Schie RM, De Boer A, Teichert M, Visser LE, Maitland-Van Der Zee AH; EU-PACT Group. Long-term anticoagulant effects of the CYP2C9 and VKORC1 genotypes in acenocoumarol users. J Thromb Haemost. 2012 Apr;10(4):606-14. doi: 10.1111/j.1538-7836.2012.04633.x.
Avery PJ, Jorgensen A, Hamberg AK, Wadelius M, Pirmohamed M, Kamali F; EU-PACT Study Group. A proposal for an individualized pharmacogenetics-based warfarin initiation dose regimen for patients commencing anticoagulation therapy. Clin Pharmacol Ther. 2011 Nov;90(5):701-6. doi: 10.1038/clpt.2011.186. Epub 2011 Sep 28.
van Schie RM, Wessels JA, le Cessie S, de Boer A, Schalekamp T, van der Meer FJ, Verhoef TI, van Meegen E, Rosendaal FR, Maitland-van der Zee AH; EU-PACT Study Group. Loading and maintenance dose algorithms for phenprocoumon and acenocoumarol using patient characteristics and pharmacogenetic data. Eur Heart J. 2011 Aug;32(15):1909-17. doi: 10.1093/eurheartj/ehr116. Epub 2011 Jun 2. Erratum in: Eur Heart J. 2013 Jun;34(24):1854.
van Schie RM, Wessels JA, Verhoef TI, Schalekamp T, le Cessie S, van der Meer FJ, Rosendaal FR, Visser LE, Teichert M, Hofman A, Buhre PN, de Boer A, Maitland-van der Zee AH. Evaluation of the effect of genetic variations in GATA-4 on the phenprocoumon and acenocoumarol maintenance dose. Pharmacogenomics. 2012 Dec;13(16):1917-23. doi: 10.2217/pgs.12.174.
Verhoef TI, Zuurhout MJ, van Schie RM, Redekop WK, van der Meer FJ, le Cessie S, Schalekamp T, de Boer A, Maitland-van der Zee AH. The effect of omeprazole and esomeprazole on the maintenance dose of phenprocoumon. Br J Clin Pharmacol. 2012 Dec;74(6):1068-9. doi: 10.1111/j.1365-2125.2012.04295.x.
van Schie RM, de Boer A, Maitland-van der Zee AH. Implementation of pharmacogenetics in clinical practice is challenging. Pharmacogenomics. 2011 Sep;12(9):1231-3. doi: 10.2217/pgs.11.81.
van Schie RM, Cascorbi I, Maitland-van der Zee AH. Conference Scene: Pharmacogenomics at the second PharmSciFair 2009: adverse drug reactions and clinical implementation. Pharmacogenomics. 2009 Sep;10(9):1389-91. doi: 10.2217/pgs.09.95.

Responsible Party: Anke-Hilse Maitland-van der Zee, PharmD, PhD, Utrecht Institute for Pharmaceutical Sciences
ClinicalTrials.gov Identifier: NCT01119300     History of Changes
Other Study ID Numbers: COU-001W
First Submitted: May 4, 2010
First Posted: May 7, 2010
Last Update Posted: December 3, 2014
Last Verified: December 2014

Keywords provided by Anke-Hilse Maitland-van der Zee, Utrecht Institute for Pharmaceutical Sciences:
Venous Thromboembolism (VTE)
Atrial Fibrillation (AF)

Additional relevant MeSH terms:
Atrial Fibrillation
Thromboembolism
Venous Thromboembolism
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Embolism and Thrombosis
Vascular Diseases
Warfarin
Anticoagulants


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