Edoxaban vs. warfarin in patients with atrial fibrillation on amiodarone: a subgroup analysis of the ENGAGE AF-TIMI 48 trial

Background In the ENGAGE AF-TIMI 48 trial, the higher-dose edoxaban (HDE) regimen had a similar incidence of ischaemic stroke compared with warfarin, whereas a higher incidence was observed with the lower-dose regimen (LDE). Amiodarone increases edoxaban plasma levels via P-glycoprotein inhibition. The current pre-specified exploratory analysis was performed to determine the effect of amiodarone on the relative efficacy and safety profile of edoxaban. Methods and results At randomization, 2492 patients (11.8%) were receiving amiodarone. The primary efficacy endpoint of stroke or systemic embolic event was significantly lower with LDE compared with warfarin in amiodarone treated patients vs. patients not on amiodarone (hazard ratio [HR] 0.60, 95% confidence intervals [CIs] 0.36-0.99 and HR 1.20, 95% CI 1.03-1.40, respectively; P interaction <0.01). In patients randomized to HDE, no such interaction for efficacy was observed (HR 0.73, 95% CI 0.46-1.17 vs. HR 0.89, 95% CI 0.75-1.05, P interaction = 0.446). Major bleeding was similar in patients on LDE (HR 0.35, 95% CI 0.21-0.59 vs. HR 0.53, 95% CI 0.46-0.61, P interaction = 0.131) and HDE (HR 0.94, 95% CI 0.65-1.38 vs. HR 0.79, 95% CI 0.69-0.90, P interaction = 0.392) when compared with warfarin, independent of amiodarone use. Conclusions Patients randomized to the LDE treated with amiodarone at the time of randomization demonstrated a significant reduction in ischaemic events vs. warfarin when compared with those not on amiodarone, while preserving a favourable bleeding profile. In contrast, amiodarone had no effect on the relative efficacy and safety of HD

Enoxaparin is superior to unfractionated heparin for preventing clinical events at 1-year follow-up of TIMI 11B and ESSENCE

Background Enoxaparin treatment is associated with a 20% reduction in clinical events during the acute phase of management of patients with unstable angina/non ST elevation myocardial infarction. Interest in the use of enoxaparin would be enhanced further if evidence of a durable treatment benefit over the long term could be provided. Methods Event rates at 1 year for the composite end-point of death/non-fatal myocardial infarction/urgent revascularization and its individual components were ascertained from the TIMI 11B and ESSENCE databases. Results There was no evidence of heterogeneity between TIMI 11B and ESSENCE in tests for interactions between treatment and trial. A significant treatment benefit of enoxaparin on the rate of death/non-fatal myocardial infarction/urgent revascularization was observed at 1 year (hazard ratio 0·88; P=0·008). The event rate was 25·8% in the unfractionated heparin group and 23·3% in the enoxaparin group, an absolute difference of 2·5%. A progressively greater treatment benefit of enoxaparin was observed as the level of patient risk at baseline increased. Treatment effects for the individual end-point elements ranged from 9–14%, favouring enoxaparin. Conclusions The stable absolute difference in event rates of 2·5% seen at 8 days and again at 1 year favouring enoxaparin may be due to more effective control of the thrombotic process surrounding the index event. Once the pharmacological effect of enoxaparin had dissipated there was no rebound increase in events. Thus, those patients who had received enoxaparin acutely were protected from experiencing a deterioration of the original therapeutic benefit. These findings regarding enoxaparin add to the data to be considered by clinicians when selecting an antithrombin for the acute phase of management of unstable angina/non-ST elevation myocardial infarction

The impact of renal dysfunction on outcomes in the ExTRACT-TIMI 25 trial.

Contains fulltext : 52103.pdf (publisher's version ) (Closed access)OBJECTIVES: The ExTRACT-TIMI 25 (Enoxaparin and Thrombolysis Reperfusion for Acute Myocardial Infarction Treatment-Thrombolysis In Myocardial Infarction 25) trial provided the opportunity to evaluate the impact of renal dysfunction on outcomes in patients with ST-segment elevation myocardial infarction (STEMI) and compare enoxaparin (ENOX) and unfractionated heparin (UFH). BACKGROUND: It is unclear how renal dysfunction influences the balance between benefit and risk of antithrombotic therapy. METHODS: In the ExTRACT-TIMI 25 trial, 20,479 patients were randomized to UFH or ENOX. A reduced ENOX dose was administered to patients age > or =75 years and those with an estimated creatinine clearance (CrCl) 60 ml/min (79.1% of the study population). Major bleeding and intracranial hemorrhage did not differ for patients with preserved renal function (CrCl >90 ml/min), but in those with renal dysfunction there was a progressively greater increase in the risk of major and minor bleeding with ENOX. CONCLUSIONS: Enoxaparin was superior to UFH for the majority of subjects. With more severe renal dysfunction, the net clinical benefit between ENOX and UFH did not differ, despite the rise in adverse events in both treatment groups. Future studies should take renal dysfunction into account when assessing antithrombotic regimens