Is a novel anticoagulant right for your patient?

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Applied Evidence

Is a novel anticoagulant right for your patient?

J Fam Pract. 2014 January;63(1):22-28

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References

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Who should not take a NOAC?The most effective therapy for patients who need rapid reversal of any NOAC is to administer 75 to 80 unites/kg of activated prothrombin complex concentrate.

NOACs should not be prescribed for patients with mechanical heart valves.³⁴ Dabigatran is the only NOAC to have been studied in this patient population, and the phase II trial was stopped prematurely due to increased risk for both bleeding and stroke in patients on dabigatran compared with warfarin.³⁴

Renal impairment must be considered, as well. Do a baseline assessment of renal function in all patients before transitioning them to a NOAC, and periodic reassessment during therapy. While this is important for patients on rivaroxaban and apixaban, it is essential for those on dabigatran, as 80% of the drug is excreted by the kidneys.^1,5,12 NOACs have not been adequately assessed in patients with severe renal dysfunction and should be avoided in this patient population. Caution should be exercised in patients with moderate renal dysfunction, as well.^5-10,14-19 Apixaban appears to be the safest NOAC for patients with moderate renal dysfunction, as it has the least renal clearance.^1,12

Who should take a NOAC?

No well-established criteria for patient selection for NOACs exist, yet appropriate patient selection is crucial. Evidence suggests that NOAC therapy is best suited to those who:
• are relatively young (<65 years)
• have normal renal function
• have poorly controlled INR with warfarin that is unrelated to noncompliance
• are unable to have regular INR monitoring.

NOACs have not been adequately assessed in severe renal dysfunction and should be avoided in this patient population.Patients best suited for continued use of warfarin would be those whose INR is well controlled, those who have higher goal INR ranges (eg, because of the presence of mechanical heart valves), patients with significant renal dysfunction, and individuals with a history of peptic ulcer disease or GI bleeding. Warfarin may also be the best option for patients with a history of noncompliance and for uninsured or underinsured patients.

CASE 1 Warfarin and any of the NOACs were all feasible options for Ms. J, but apixaban was deemed to be the safest because of her moderate renal dysfunction. However, after she was told that apixaban has little “real world” clinical data, no effective antidote if bleeding were to occur, and a much higher cost than warfarin, she opted for warfarin therapy, despite the laboratory monitoring required.

CASE 2 Mr. W was excited to learn that there were new alternatives to warfarin; he had taken warfarin for 6 months after his last DVT and had a hard time coming in for INR checks. The patient reported that he had no history of bleeding and was compliant with medications. Rivaroxaban was the best option for Mr. W, as it is the only NOAC with FDA approval for the treatment of acute VTE.

CORRESPONDENCE
Jeremy Vandiver, PharmD, BCPS, Swedish Medical Center, Room 3260, 501 East Hampden Avenue, Englewood, CO 80013; jvandiver@uwyo.edu