Apixaban-Calibrated Anti-FXa Activity in Relation to Outcome Events and Clinical Characteristics in Patients with Atrial Fibrillation: Results from the AVERROES Trial

Vinai C Bhagirath, John W Eikelboom, Jack Hirsh, Michiel Coppens, Jeffrey Ginsberg, Thomas Vanassche, Fei Yuan, Noel Chan, Salim Yusuf, Stuart J Connolly, Vinai C Bhagirath, John W Eikelboom, Jack Hirsh, Michiel Coppens, Jeffrey Ginsberg, Thomas Vanassche, Fei Yuan, Noel Chan, Salim Yusuf, Stuart J Connolly

Abstract

Background In patients with nonvalvular atrial fibrillation (AF), apixaban is given in doses of 5 or 2.5 mg twice daily, according to clinical characteristics. The usual on-treatment range of apixaban drug levels, as determined by apixaban-calibrated anti-factor Xa (anti-Xa) activity, has previously been measured in small cohorts; however, the association between anti-Xa activity and clinical outcomes and the predictors of variability in anti-Xa activity have not been well studied in the AF population. Methods and Results Anti-Xa activity was measured before taking the morning dose, 3 months after enrollment in the AVERROES study using a calibrated anti-Xa assay (Rotachrom). Patients with two of the following criteria-age >80; weight <60 kg; or creatinine >133 μg/L-received 2.5 mg twice daily ( n = 145), while all others received 5 mg twice daily ( n = 2,247). A total of 2,392 patients were included, with median follow-up of 1.1 years. Median apixaban anti-Xa activity was 122 ng/mL (interquartile range [IQR]: 63-198 ng/mL) for the entire group; 99 ng/mL (IQR: 60-146 ng/mL) for the 2.5-mg group; and 125 ng/mL (IQR: 64-202 ng/mL) for the 5-mg group ( p = 0.003). A relationship was evident between bleeding and anti-Xa activity ( p = 0.01), which was driven by minor bleeding. No relationship was evident between major bleeding or stroke/systemic embolism and anti-Xa activity. In those receiving the 5-mg dose, estimated glomerular filtration rate, sex, and age had the strongest association with anti-Xa activity. Conclusion There is considerable variability in anti-Xa activity among AF patients receiving apixaban. Rates of major bleeding and stroke/systemic embolism were low irrespective of anti-Xa activity. Clinical Trial Registration ClinicalTrials.gov NCT00496769; https://ichgcp.net/clinical-trials-registry/NCT00496769 .

Keywords: apixaban; fibrillation; hemorrhage; systemic embolism.

Conflict of interest statement

Conflict of Interest None declared.

Figures

Fig. 1
Fig. 1
Apixaban-calibrated anti-Xa activity by dose. Blood samples were drawn immediately prior to the morning dose of apixaban. Boxes represent median and interquartile range, whiskers represent 10th to 90th centiles, and points represent minimum and maximum.
Fig. 2
Fig. 2
Stroke/systemic embolism and bleeding versus anti-Xa activity. Predicted probability of (A) stroke/systemic embolism; or (B) bleeding of any severity (minor, clinically relevant nonmajor, or major) versus anti-Xa activity. The shaded region represents the 95% confidence interval.

References

    1. Granger C B, Alexander J H, McMurray J J et al.Apixaban versus warfarin in patients with atrial fibrillation. N Engl J Med. 2011;365(11):981–992.
    1. Connolly S J, Eikelboom J, Joyner C et al.Apixaban in patients with atrial fibrillation. N Engl J Med. 2011;364(09):806–817.
    1. Halvorsen S, Atar D, Yang H et al.Efficacy and safety of apixaban compared with warfarin according to age for stroke prevention in atrial fibrillation: observations from the ARISTOTLE trial. Eur Heart J. 2014;35(28):1864–1872.
    1. Ng K H, Shestakovska O, Connolly S J et al.Efficacy and safety of apixaban compared with aspirin in the elderly: a subgroup analysis from the AVERROES trial. Age Ageing. 2016;45(01):77–83.
    1. Hohnloser S H, Hijazi Z, Thomas L et al.Efficacy of apixaban when compared with warfarin in relation to renal function in patients with atrial fibrillation: insights from the ARISTOTLE trial. Eur Heart J. 2012;33(22):2821–2830.
    1. Easton J D, Lopes R D, Bahit M C et al.Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a subgroup analysis of the ARISTOTLE trial. Lancet Neurol. 2012;11(06):503–511.
    1. Gage B F, Waterman A D, Shannon W, Boechler M, Rich M W, Radford M J. Validation of clinical classification schemes for predicting stroke: results from the National Registry of Atrial Fibrillation. JAMA. 2001;285(22):2864–2870.
    1. Schulman S, Kearon C; Subcommittee on Control of Anticoagulation of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis.Definition of major bleeding in clinical investigations of antihemostatic medicinal products in non-surgical patients J Thromb Haemost 2005304692–694.
    1. Levey A S, Stevens L A, Schmid C H et al.A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009;150(09):604–612.
    1. Barrett Y C, Wang Z, Frost C, Shenker A. Clinical laboratory measurement of direct factor Xa inhibitors: anti-Xa assay is preferable to prothrombin time assay. Thromb Haemost. 2010;104(06):1263–1271.
    1. Kowalsk K, Nielsen J, Roy Aet al.Apixaban exposure and anti-Xa activity in nonvalvular atrial fibrillation patients: an application of population PK/PD analysis J Pharmacokinet Pharmacodyn 201441S7–S101.. Abstract M-027
    1. Osanai H, Ajioka M, Masutomi T et al.Measurement of anti-factor Xa activity in patients on apixaban for non-valvular atrial fibrillation. Circ J. 2015;79(12):2584–2590.
    1. Testa S, Tripodi A, Legnani C et al.Plasma levels of direct oral anticoagulants in real life patients with atrial fibrillation: results observed in four anticoagulation clinics. Thromb Res. 2016;137:178–183.
    1. Reilly P A, Lehr T, Haertter S et al.The effect of dabigatran plasma concentrations and patient characteristics on the frequency of ischemic stroke and major bleeding in atrial fibrillation patients: the RE-LY Trial (Randomized Evaluation of Long-Term Anticoagulation Therapy) J Am Coll Cardiol. 2014;63(04):321–328.
    1. Ruff C T, Giugliano R P, Braunwald Eet al.Association between edoxaban dose, concentration, anti-Factor Xa activity, and outcomes: an analysis of data from the randomised, double-blind ENGAGE AF-TIMI 48 trial Lancet 2015385(9984):2288–2295.
    1. Hanna M S, Mohan P, Knabb R, Gupta E, Frost C, Lawrence J H. Development of apixaban: a novel anticoagulant for prevention of stroke in patients with atrial fibrillation. Ann N Y Acad Sci. 2014;1329:93–106.
    1. Steinberg B A, Shrader P, Thomas L et al.Off-label dosing of non-vitamin K antagonist oral anticoagulants and adverse outcomes: The ORBIT-AF II Registry. J Am Coll Cardiol. 2016;68(24):2597–2604.

Source: PubMed

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