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.