Warfarin: do we need genotype-based dose prediction?

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Yenny Yenny


For the treatment and prevention of thrombo-embolic disease, the most frequently used anticoagulant drug worldwide is warfarin, an oral coumarin derivative, with more than 30 million prescriptions written for this drug in the United States in 2004.(1) The drug has a narrow therapeutic index and its metabolism varies by as much as a factor of 10 among individual patients, making warfarin therapy difficult to manage. Hemorrhagic complication rates of warfarin are estimated to be 5-7.9% for major (life threatening) hemorrhage and 14-36% for minor hemorrhage (e.g. nosebleeds, microscopic hematuria).(2) This condition makes it difficult to establish the appropriate dose of warfarin.

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How to Cite
Yenny, Y. (2016). Warfarin: do we need genotype-based dose prediction?. Universa Medicina, 29(3), i-iii. https://doi.org/10.18051/UnivMed.2010.v29.i-iii
Review Article


Wysowski DK, Nourjah P, Swartz L. Bleeding complications with warfarin use: a prevalent adverse effect resulting in regulatory action. Arch Intern Med 2007;167:1414-9.

Hylek EM, Evans-Molina C, Shea C, Henault LE, Regan S. Major hemorrhage and tolerability of warfarin in the firs years of therapy among elderly patients with atrial fibrillation. Circulation 2007;115:2689-96.

Limdi NA, Veenstra DL. Warfarin pharmacogenetics. Pharmacotherapy 2009;28:1084-97.

Osinbowale O, Malki MA, Schade A, Bartholomew JR. An algorithm for managing warfarin resistance. Cleve Clin J Med 2009;76:724-30.

Scott SA, Edelmann L, Kornreich R, Desnick RJ. Warfarin pharmacogenetics: CYP2C9 and VKORC1 genotypes predict different sensitivity and resistance frequencies in the Ashkenazi and Sephardic Jewish population. Am J Hum Genet 2008;82:495-500.

Sanderson S, Emery J, Higgins. CYP2C9 gene variants, drug dose, and bleeding risk in warfarin-treated patients: A HUGEnet systematic review and meta-analysis. Genet Med 2005;7:97-104.

D’Ambrosio RL, D’Andrea G, Cafolla A, Faillace F, Margaglione M. A new vitamin K epoxide reductase complex subunit-1 (VKORC1) mutation in a patient with decreased stability of CYP2C9 enzyme. J Thrombo Haemost 2007;5:191-3.

Bentley DP, Backhouse G, Hutching A, Haddon RL, Spragg B, Routledge PA. Investigation of patients with abnormal response to warfarin. Br J Clin Pharmacol 1986;22:37-41.

Food and Drug Administration (FDA) approves updated warfarin (coumadin) prescribing information. New genetic information may help providers improve initial dosing estimates of the anticoagulant for individual patients. Available at: http://www.fda.gov/cder/drug/infopage/warfarin/default.htm. Accessed July 7, 2010.

The International Warfarin Pharmacogenetic Consortium. Estimation of the warfarin dose with clinical and pharmacogenetic data. N Engl J Med 2009;360:753-64.