Comparing outcomes using low‐dose apixaban and anti‐Xa monitoring and vitamin K antagonists in patients with renal replacement therapy

Background Guidelines recommend oral anticoagulation for stroke prevention in atrial fibrillation and secondary prevention of venous thromboembolism. Outside the United States, apixaban is unlicensed for use in patients with end‐stage renal disease (ESRD) receiving renal replacement therapy (RRT). Aim To compare thrombotic and safety outcomes in patients receiving either vitamin K antagonists (VKAs) or apixaban 2.5 mg twice daily in the context of ESRD and RRT. Method Retrospective service evaluation comparing bleeding and thrombotic outcomes in patients treated with apixaban 2.5 mg BD or VKA in a tertiary anticoagulation clinic. Trough anti‐Xa levels of apixaban patients were reviewed. Clinical features and outcomes were reviewed using electronic patient records. Results Fifty‐five VKA and 33 apixaban patients were included in the analysis. There were no major bleeds in the apixaban cohort compared with 4 (7.3%) in the VKA cohort ( χ 2 = 2.667, p = 0.102). No difference in time to major or clinically relevant non‐major bleeding (CRNMB) was found ( χ 2 = 1.252, p = 0.263). Rates of thrombotic events (all stroke) were 1 vs . 3 (1.1 and 7.1 events/100 patient‐years) for VKA and apixaban, respectively ( χ 2 = 3.291, p = 0.070). Only one stroke was related to AF. Eighty‐four of 85 trough anti‐Xa levels analysed were below the upper limit of normal of the reference range for the general population. Discussion Our results suggest similar outcomes with VKA and apixaban in those receiving RRT, indicating apixaban may be a viable second‐line treatment option in those for whom VKA may not be appropriate. Further investigation into the safety of the apixaban 5‐mg regimen is warranted.