Pharmacogenetic testing for selected conditions / anticoagulants
There are a growing number of genetic tests and panels of genetic tests designed to inform decisions on the selection and dosage of oral anticoagulant medications. Potential benefits of these tests are more appropriate treatment decisions and better patient outcomes, including avoiding treatment-related side effects.
Primary criteria ranking
- Safety = Low
- Efficacy = High
- Cost = Medium/ High
Assessment timeline (2018)
- Draft key questions published: January 8, 2018
- Public comment period: January 8 to January 22, 2018
- Final key questions published: January 31, 2018
- Draft report published: March 9, 2018
- Public comment period: March 9 to April 9, 2018
- Final report published: April 18, 2018
- HTCC public meeting: May 18, 2018
Anticoagulant drugs, commonly known as blood thinners, are used for patients with conditions such as atrial fibrillation, deep venous thrombosis, or orthopedic surgery to prevent stroke, pulmonary embolism, or other complications from having a blood clot.1 Warfarin, approved for use in the U.S. in 1954, is the most commonly prescribed oral anticoagulant, although use of direct oral anticoagulants (DOACs) is increasing.2 When prescribing anticoagulants, the risk of thrombosis from the underlying condition needs to be weighed against the risk of bleeding from anticoagulation.3 Clinical decisions about which of these agents to use depend on the underlying indication for anticoagulation and other considerations such as the patient’s creatinine clearance (a measure of renal function), other medications used, and history of serious bleeding. Achieving effective anticoagulation can require time, laboratory testing, and dose adjustments, particularly for Warfarin.4 For example, diet, comorbidities, and interactions with other medications can lead to wide variation in warfarin dose requirements.4 Genetic variations are known to change patient response to various medications, and efforts to personalize therapy according to genetic differences have gained momentum.1 This report will examine the clinical usefulness of genetic tests to guide initiation or dosage adjustments for oral anticoagulant drugs.
1. Shi C, Yan W, Wang G, Wang F, Li Q, Lin N. Pharmacogenetics-based versus conventional dosing of warfarin: a meta-analysis of randomized controlled trials. PLoS One. 2015;10(12):e0144511.
2. Harter K, Levine M, Henderson SO. Anticoagulation drug therapy: a review. The Western Journal of Emergency Medicine. 2015;16(1):11-17.
3. Michigan Anticoagulation Quality Improvement Initiative. Anticoagulation toolkit. 2017; http://anticoagulationtoolkit.org/sites/default/files/toolkit_pdfs/toolkitfull.pdf
4. Emery JD. Pharmacogenomic testing and warfarin: what evidence has the GIFT trial provided? JAMA. 2017;318(12):1110-1112.