Spontaneous adverse event reports associated with apixaban and potentially inappropriate medicine use: an international comparison
Date
2015
Authors
Caughey, G.E.
Kalisch Ellett, L.M.
Barratt, J.D.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Conference item
Citation
Pharmacoepidemiology and Drug Safety, 2015, vol.24, iss.S1, pp.111-111
Statement of Responsibility
Conference Name
31st International Conference on Pharmacoepidemiology and Therapeutic Risk Management (22 Aug 2015 - 26 Aug 2015 : Massachesetts, USA)
Abstract
Background: Apixaban is a new oral anticoagulant recently approved for prevention of stroke in patients with atrial fibrillation or prophylaxis of deep vein thrombosis after knee or hip replacement. Recent meta-analyses have been inconclusive with regard to risk of bleeding compared with warfarin. Safety concerns remain regarding apixaban's potential to increase bleeding risk and the current lack of an antidote to reverse its anticoagulant effects.Objectives: The study aimed to analyse spontaneous adverse event reports associated with apixaban from Australia, Canada and the USA and to examine potentially inappropriate concomitant medicine use which may place patients at increased risk of adverse events.Methods: Spontaneous adverse event national databases from Australia, Canada and the USA were used to examine reports of adverse events associated with apixaban from 1 January 2012 to 30 September 2014. Disproportionality analyses including proportional reporting ratio (PRR) and reporting odds ratio (ROR) were conducted for the quantitative detection of signals using the USA database. Concomitant medicine use was also identified from reports.Results: Haemorrhage was the most common reported adverse event, ranging from 26% of reports for Australia to 30.9% for Canada. Gastrointestinal (GI) haemorrhage accounted for 36.7% of Australian, 50% of Canadian and 58.8% of the USA haemorrhage adverse event reports. Positive signals were confirmed in the USA data (all haemorrhage: PRR 4.03, χ2 36.11 and ROR 4.16, 95%CI [2.6, 6.8]; GI haemorrhage: PRR 5.7, χ2 34.35 and ROR 5.81, 95%CI [3.1, 10.9]). Across all three countries, almost half of all adverse events for apixaban reported concomitant use of medicines with the potential to increase bleeding risk, ranging from 47.6% in Canada to 65.5% in Australia.Conclusions: A large proportion of adverse events for apixaban were associated with concomitant medicine use, which may have placed the patient at increased risk of adverse events, in particular haemorrhage. Increased awareness of patients' comorbidity and associated medicine use is required to minimise risk and ensure the safe and effective use of apixaban in clinical practice.