Lessons learnt from local real-life experience with idarucizumab for the reversal of dabigatran.

Abstract

Idarucizumab is a specific antidote for the direct thrombin inhibitor oral anticoagulant dabigatran etexilate. It has been used with increasing frequency in Australia since it was granted Therapeutic Goods Administration approval in October 2016. To assess idarucizumab usage, effect on coagulation parameters and clinical outcomes in patients who received idarucizumab in Western Sydney Local Health District (WSLHD). A retrospective audit was conducted of all patients who received idarucizumab in WSLHD between September 2015 and December 2017. Of the 23 patients who received idarucizumab, 17 (74%) had bleeding, and 6 (26%) required urgent surgery/procedure. Thrombin time (TT) or activated partial thromboplastin time (APTT, when TT not available) remained prolonged at 24 h post-idarucizumab infusion in 10 of 20 (50%) patients. Renal impairment at admission was associated with prolonged TT/APTT at 24 h (P = 0.02). Of the six (26%) patients who died during hospital admission, five had raised TT/APTT at 24 h (P = 0.05). Two deaths were due to continued bleeding despite idarucizumab. Only 17% of patients received prohaemostatic treatments, and none received plasma derivatives. Despite assay availability, dabigatran drug level was only measured in eight patients. Idarucizumab helped achieve haemostasis in 15 bleeding patients and allowed 6 patients to undergo urgent surgery. Half the patients had prolonged TT/APTT at 24 h post-idarucizumab, which was more likely to occur in patients with impaired renal function.