patients in the first one to two years after acute coronary syndrome. The reduction of major bleeding, and especially ICH, of NOACs compared with VKAs promises improvement of the outcome of patients treated with long-term anticoagulation. However, the fixed-dose regimens of NOACs and increased ease of use for patients should not lead to complacency. If the most favourable Phase III trial results are to apply to patients in daily practice, the best approach is to use these drugs as they were tested in these trials. One of the arguments of the US Food and Drug Administration (FDA) to only approve the 150mg BID dose of dabigatran was the expectation that physicians would too often prescribe the 110mg BID dose with the aim to reduce bleeding, and thereby giving up the superior stroke protection of the 150mg BID dose. Interestingly, in a recent report from the Dresden prospective NOAC registry, 20% of patients treated with apixaban for AF received a reduced dose of 2.5mg BID,31
whereas in the Phase III
Although dose reductions will likely further reduce the risk of bleeding, it is uncertain to what extent the protective effect on ischemic stroke is lost and what the net clinical effect of such a strategy is. Interestingly, for secondary prevention of VTE, dose reduction may be the way forward. The AMPLIFY extension study compared apixaban 5mg and 2.5mg BID with placebo in patients who completed six months of anticoagulation after acute VTE.1
trial, only 5% were eligible for dose reduction.9
Both apixaban doses
showed a similar 80% risk reduction for recurrent VTE but the lower 2.5mg BID showed a non-significant trend of a 25% reduction of major or clinically relevant non-major bleeding. A similar trial evaluating a 50% dose reduction of rivaroxaban for secondary prevention is ongoing.32
If in this trial a 50% reduced
dose would be similarly effective as a full dose but would reduce the risk of bleeding, long-term secondary prevention of VTE is likely to change accordingly.
Safety can be facilitated by regular education and training for all staff involved in the care of patients receiving anticoagulant therapy. Thus, patient safety in anticoagulation management can be successfully achieved through familiarising healthcare professionals of the risks and benefits of anticoagulation therapy. l
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