Home' Australian Pharmacist : Australian Pharmacist June 2015 Contents Australian Pharmacist June 2015 I ©Pharmaceutical Society of Australia Ltd.
CONTINUING PROFESSIONAL DEVELOPMENT
1. What position is taken in the current
CPIC guidelines for warfarin dosing?
a) Dosing algorithms should only
incorporate genetic data.
b) Dosing algorithms which incorporate
genetic data outperform both dosing
algorithms which do not incorporate
genetic data and fixed dosing
c) Fixed dosing guidelines is the
d) Dosing algorithms are not routinely
recommended for warfarin dosing .
2. Clinical variables taken into account
in the dosing algorithms discussed in
the article include:
a) Age, gender and body mass index.
b) Co-morbid conditions with increased
risk of bleeding or thromboembolism.
c) Use of anti-arrhythmics such as
amiodarone, statins, azoles or certain
d) All of the above.
3. The following factors can all affect
clinical trial outcomes. Which
is MOST likely to be driving the
controversy surrounding warfarin
b) Treatment setting.
c) Cohort characteristics.
d) Study power.
4. Which of the following statements
about genetic factors relating to
warfarin dosing is MOST likely to be
CORRECT based on current evidence?
a) Considering both clinical and genetic
factors is better than fixed dose
schedules but offers no advantages over
clinical factors alone at any time during
b) Considering both clinical and genetic
factors is unlikely to benefit clinical
outcomes significantly beyond the peri-
c) Considering both clinical and genetic
factors is likely to provide significant
benefits over other approaches during
the peri-initiation period and beyond.
d) None of the above.
currently occurring with the PREDICT
study mentioned above.
warfarin pharmacogenomics together
with gene variants affecting clopidogrel,
simvastatin, thiopurines and tacrolimus.
As increasing numbers of people
have genomic testing, it now appears
likely that consideration of warfarin
pharmacogenomic test data will slowly
but inexorably enter routine practice.
Pharmacogenomic tests for warfarin
are likely to benefit some patients,
particularly those at risk of major
bleeding and thromboembolic events,
although the clinico‐economic benefits
of widespread pharmacogenomic
testing for warfarin dosing remain to
NPS MedicineWise. Warfarin safety vital for thousands
of Australians. 2013. At: www.nps.org.au/media-centre/
US Food and Drug Administration (FDA). 2015. Table
of pharmacogenomic biomarkers in drug labeling. At:
Pharmacogenomics Knowledge Base (PharmGKB) and
Clinical Pharmacogenetics Implementation Consortium
(CPIC). 2014. At: www.pharmgkb.org/drug/PA451906
1. Campbell P, Roberts G, Park D, et al. Managing warfarin
therapy in the community. Australian Prescriber
2. Beitelshees AL, Deepak V, Joshua LP. Personalized
antiplatelet and anticoagulation therapy: applications and
significance of pharmacogenomics. Pharmacogenomics
and Personalized Medicine 2015;8:43–61.
3. Tran HA, Chunilal SD, Harper PL, et al. An update of
consensus guidelines for warfarin reversal. Med J Aust
4. Linkins LA, Choi PT, Douketis JD. Clinical impact of
bleeding in patients taking oral anticoagulant therapy for
venous thromboembolism: a meta-analysis. Ann Intern
Med 2003;139(11): 893–900.
5. NPS Medicine Wise. Warfarin safety vital for thousands
of Australians. 2013. At: www.nps.org.au/media-centre/
6. Pharmaceutical Society of Australia. Submission to the
2013–14 Federal budget. Australians stay healthier: quality
use of subsidised medicines. Canberra:PSA; 2012. At: www.
7. Klein TE, Altman RB, Eriksson N, et al. Estimation of the
warfarin dose with clinical and pharmacogenetic data. N
Engl J Med 2009;360(8):753–64.
8. Rossi et al. Australian Medicines Handbook Adelaide:
Australian Medicines Handbook; 2015.
9. Johnson JA, Cavallari LH. Warfarin pharmacogenetics.
Trends Cardiovasc Med 2015;25(1):33–41 .
10. Verhoef TI, Ragia G, de Boer A, et al. A randomized trial
of genotype-guided dosing of acenocoumarol and
phenprocoumon. N Engl J Med 2013;369(24): 2304–12.
11. Australian Government Department of Health.
Pharmaceutical Benefits Scheme. Review of
anticoagulation therapies in atrial fibrillation; 2012. At:
12. American Medical Association. Personalized health
care report 2008: warfarin and genetic testing; 2008. At:
13. Li X, Yang J, Wang X, et al. Clinical benefits of
pharmacogenetic algorithm-based warfarin dosing:
meta-analysis of randomized controlled trials. Thromb Res
2015;135(4): 621–9 .
14. Kearon C, Akl EA, Comerota AJ, et al. Antithrombic therapy
for VTE disease: antithrombic therapy and prevention
thrombosis, 9th ed: American College of Chest Physicians
evidence-based clinical practice guidelines. Chest
15. Gage BF, Eby C, Johnson JA, et al. Use of pharmacogenetic
and clinical factors to predict the therapeutic dose of
warfarin. Clin Pharmacol Ther 2008;84(3):326–31.
16. Pharmacogenomics Knowledge Base (PharmGKB) and
Clinical Pharmacogenetics Implemantation Consortium
(CPIC). Warfarin. 2014. At: www.pharmgkb.org/drug/
17. Wadelius M, Chen LY, Lindh JD, et al. The largest
prospective warfarin-treated cohort supports genetic
forecasting. Blood 2009;113(4):784–92.
18. Finkelman BS, Gage BF, Johnson JA, et al. Genetic warfarin
dosing: tables versus algorithms. J Am Coll Cardiol
19. Pirmohamed M, Burnside G, Eriksson N, et al. A
randomized trial of genotype-guided dosing of warfarin.
N Engl J Med 2013;369(24):2294–2303.
20. Kimmel SE, French B, Kasner SE, et al. A pharmacogenetic
versus a clinical algorithm for warfarin dosing. N Engl J
Med 2013;369(24):2283–93 .
21. Zineh I, Pacanowski M, Woodcock J. Pharmacogenetics
and coumarin dosing-recalibrating expectations. N Engl J
22. DNAdose. 2015. At: www.dnadose.com.au/
23. The Royal College of Pathologists of Australasia (RCPA).
Catalogue of genetic tests and laboratories. 2009. At:
24. Van Driest SL, Shi Y, Bowton EA, et al. Clinically actionable
genotypes among 10,000 patients with preemptive
pharmacogenomic testing. Clin Pharmacol Ther
25. Johnson JA, Gong L, Whirl-Carrillo M, et al. Clinical
Pharmacogenetics Implementation Consortium (CPIC)
Guidelines for CYP2C9 and VKORC1 genotypes and
warfarin dosing. Clin Pharmacol Ther 2011;90(4):625–9 .
26. Australian Government, Department of Health and
Ageing. Review of anticoagulation therapies in atrial
fibrillation. Canberra: Commonwealth of Australia; 2012.
Links Archive Australian Pharmacist May 2015 Australian Pharmacist July 2015 Navigation Previous Page Next Page