New Kids on the Block: A case based review of the NOACs - Marc Zumberg Associate Professor Division of Hematology/Oncology
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New Kids on the Block: A case
based review of the NOACs
<
Marc Zumberg
Associate Professor
Division of Hematology/Oncology
May 2013
Disclosures – None – http://coi.med.ufl.edu/
Comparison of warfarin vs. New
Oral Anticoagulants
Weitz. Hematology 2012. 536-540
Case 1 • Pt is a 48 yo female with valvular atrial fibrillation placed on warfarin 6 years ago – AVR 10 years prior – INR has been in range 66% of the time – No bleeding problems – No renal insufficiency – Wants to know about the NOACs
Case 1 • You recommend: – A. Continue warfarin – B. Apixiban – C. Rivaroxaban – D. Dabigatran – E. ECASA
Case 1
• You recommend:
– A. Continue warfarin
– B. Apixiban
– C. Rivaroxaban
– D. Dabigatran
– E. ECASA
– What if pt was poorly compliant with warfarin?
• Would your choice change?
Case 1 • Note all studies of the NOACs only included nonvalvular atrial fibrillation • No studies included patients with mechanical valves – Long effective half-life of warfarin may be of benefit • It is generally recommended if patients are stable and doing well on warfarin and monitoring is not prohibitive then they should remain on this agent • Pt poorly compliant on warfarin also likely to be poorly compliant with NOACs – Can monitor compliance easier on warfarin – Less effect with single missed dose
NOACs:
Atrial fibrillation
Adam. Ann Intern Med 2012;157:796-807
Case 2
• Pt is a 48 yo male with a newly diagnosed
unprovoked iliofemoral DVT
– Normal creatinine
– No bleeding risks
– No other medications
– Travels a lot
– He asks you about short and long term treatment
options for his DVT
Case 2 • You recommend which of the following for short and long anticoagulation: – A. Lovenox/Warfarin – B. Apixiban – C. Rivaroxaban – D. Dabigatran – E. Lovenox/Warfarin/ECASA – F. Stop anticoagulation after 3 months
Case 2 • You recommend for short and long term – A. Lovenox/Warfarin – B. Apixiban – C. Rivaroxaban – D. Dabigatran – E. Lovenox/Warfarin/ECASA – F. Stop anticoagulation after 3 months
Incidence of recurrent thromboembolism in patients
with idiopathic (unprovoked) and secondary VTE
Prandoni, P. et al. Haematologica 2007;92:199-205
Goldhaber. Circulation. 2011;123:664-7.
Boutitie F et al. BMJ 2011;342:bmj.d3036Nomograms to compute risk scores and estimate
cumulative rates of recurrent VTE and bleeding
Eichinger, S. et al. Circulation 2010;121:1630-1636
Beyth. Am J Med. 1998 Aug;105(2):91-9.Hazard Ratios for Venous Thromboembolism, Major
Vascular Events, and Clinically Relevant Bleeding
with ECASA use compared to placebo
Brighton TA et al. N Engl J Med 2012;367:1979-1987.VTE Conclusions
• Idiopathic VTE is a chronic condition
– Risk of recurrence remains after discontinuation of
anticoagulation
– Treat for 3 months at a minimum
– Consider indefinite anticoagulation based on:
• VTE recurrence risk
• Bleeding risk
• Patient preference
• Rivaroxaban is the only NOAC currently FDA
approved for treatment of VTE
• Extended ECASA therapy may be an optionApixaban for extended VTE Agnelli G et al. N Engl J Med 2012. DOI: 0.1056/NEJMoa1207541
Case 3: Pre-op
A 78 year-old male is on apixiban for non-
valvular atrial fibrillation (CHADS2 score 3)
– Needs semi-elective resection of a complex thigh
mass
– CrCl 45 ml/min
– No other medications
– Surgery thought to be of high bleeding risk due to
vascular involvementCase 3 • In terms of apixiban you recommend: – A. Hold 12 hours pre-op – B. Continue throughout the procedure – C. Hold 24 hours pre-op – D. Hold 48 hours pre-op – E. Hold 72 hours pre-op – F. Hold 96 hours pre-op – G. Transition to LMWH
Case 2 • In terms of apixiban you recommend: – A. Hold 12 hours pre-op – B. Continue throughout the procedure – C. Hold 24 hours pre-op – D. Hold 48 hours pre-op – E. Hold 72 hours pre-op – F. Hold 96 hours pre-op – G. Transition to LMWH
Pre-operative Connolly. J Thromb Thrombolysis. On-line March 27, 2013
How about restarting? Connolly. J Thromb Thrombolysis. On-line March 27, 2013
Case 4: Major Bleed
• 54 year-old male on dabigatran for atrial
fibrillation is brought to the ER after MVA
– Patient is unconscious
– Internal bleeding and splenic laceration on CT
– Uncertain last administration or dose
– No history of renal insufficiency
– Family providing all information
• Pt also on amiodarone, lisinopril, simvastatin, and
ketoconazoleCase 4: Trauma • In addition to supportive care and holding further dabigatran what therapy might you reconsider: No labs yet available – A. FFP – B. Protamine – C. Activated charcoal – D. Dialysis – E. Prothrombin complex concentrates – F. DDAVP – G. Recombinant VIIa
Case: Trauma • What labs would be affected by dabigatran? (ie how could you monitor if the drug is present?) – A.PT – B.PTT – C.Platelet function assay (PFA) – D.Thrombin time (TT) – E. Fibrinogen – F. None
Labs
Dabigatran Rivaroxaban Apixiban
PT Not useful May be useful Not useful
PTT Useful Not useful Not userful
Thrombin time Useful, but very Not useful Not useful
sensitive
Anti-Xa assay Not useful Useful Useful
Note labs may be useful for qualitative assessment, but
not for quantitative use
ie. not for monitoring levels
Garcia. J of Thromb and Haem. 2012; 11: 245-252Treatment • No true reversal agents for new oral anticoagulants – Activated charcoal if dabigatran ingested within hours – Dialysis helpful with dabigatran if renal failure • FFP, cryoprecipitate, platelet, protamine not generally useful • Prothrombin complex concentrates and/or recombinant VIIa may be useful – Doesn’t reverse/Not an antidote – May help generate thrombin
Dabigatran:
Guidelines for management of bleeding
Van Ryn Thromb Haemostasis 2010Interactions Lindsley. Cardiology Today. May 2012 Horn. Pharmacy Times. Online Dec 13, 2010
Case 5: Cost containment • A physician requests Rivaroxaban be added to the Shands formulary for VTE prophylaxis after total hip replacement (THR) • The VA is considering adding rivaroxaban to the formulary for atrial fibrillation • Your hospital administrators ask you whether this is cost effective
Shands/UF acquisition costs
DRUG COST
Warfarin 5mg $0.04
Enoxaparin 30mg $4.44
Enoxaparin 40mg $5.92
Rivaroxaban 10mg $5.25
Rivaroxaban 20mg $5.33
Dabigatran 75mg $3.11
Dabigatran 150mg $3.11
Apixaban 2.5mg $3.38
Apixiban 5mg $3.38THR Prophylaxis:
Rivaroxaban Efficacy
Erikkson Annu Rev Med 2011
Eriksson BI et al. N Engl J Med 2008;358:2765-2775Choices and Summary Weitz. Hematology. 2012. 536-540
New or old ? Weitz. Hematology. 2012. 536-540
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