Twice- or Once-Daily Dosing of Novel Oral Anticoagulants for Stroke Prevention: A Fixed-Effects Meta-Analysis with Predefined Heterogeneity Quality Criteria

BACKGROUND: A number of novel oral anticoagulants (direct thrombin inhibitors or factor Xa inhibitors) are in clinical use for various indications. The dosing regimens differ between twice-daily and once-daily dosing for the prevention of stroke in patients with atrial fibrillation. With the availability of the results from four phase 3 studies (>70,000 patients), we explored whether twice-daily or once-daily dosing provides better risk-benefit balance among novel oral anticoagulants. METHODS: We conducted a strict, stepwise, fixed-effects meta-analysis with predefined heterogeneity quality criteria to generate the most appropriate common estimates for twice-daily (BID) or once-daily (QD) dosing regimens. An indirect comparison of these dosing regimens with fixed-effects meta-analysis common estimates (where available), or individual compound results, was done respectively. RESULTS: Comparing indirectly BID vs QD dosing regimens resulted in hazard ratios (HR 95% confidence interval) for stroke and systemic embolism of 0.75 (0.58-0.96) for dabigatran 150 mg BID, and 0.91 (0.73-1.13) for apixaban BID vs the QD dosing regimen. For ischemic stroke, the HR of BID vs QD was 0.85 (0.69-1.05). For intracranial hemorrhage, BID vs rivaroxaban QD was 0.57 (0.37-0.88) and, vs edoxaban QD, 0.81 (0.54-1.22). Due to heterogeneity, common estimates for major bleeding QD or BID were not justified, therefore indirect comparison of regimens were not possible. All non-vitamin K antagonist oral anticoagulants reduced all-cause mortality vs warfarin with a HR of 0.90 (0.86-0.96) without differences between regimen. CONCLUSIONS: Based on the available phase 3 study evidence, the twice-daily dosing regimen of non-vitamin K antagonist oral anticoagulants appears to offer a more balanced risk-benefit profile with respect to stroke prevention and intracranial hemorrhage.