Post-Hoc Analysis of RE-MEDY™ Demonstrates Significant Real-World Net Clinical Benefit for Dabigatran Versus Warfarin in Prevention of Secondary Venous Thromboembolism
Authors: Schulman Sam , Eriksson Henry , Kakkar Ajay , Kearon Clive , Schellong Sebastian M , Mismetti Patrick , Feuring Martin , Hantel Stefan , Kreuzer Joerg , Goldhaber Samuel Z. 
Published: October 2019

Background: The double-blind, parallel-group, noninferiorityRE-MEDY™ study comparing the direct oral thrombin inhibitor dabigatran etexilate to warfarin in the prevention of secondary venous thromboembolism (VTE) showed non-inferiority of dabigatran to warfarin in both hazard ratio (HR) and risk difference for recurrent symptomatic VTE and related deaths. The benefit-risk balance of dabigatran compared to warfarin in secondary VTE prevention can be further explored by evaluating the net clinical benefit (NCB).

Methods: Patients with a diagnosis of VTE received dabigatran 150 mg twice daily (n = 1430), or warfarin adjusted to maintain an international normalized ratio (INR) of 2.0–3.0 (n = 1426), for an additional period of 6–36 months after 3–12 months of anticoagulant therapy. NCB in the RE-MEDY™ study was evaluated narrowly by (1) analyzing nonfatal recurrent VTE, nonfatal myocardial infarction (MI), nonfatal stroke, nonfatal systemic embolism, all-cause death, and major bleeding events (MBEs), and broadly by (2) including clinically relevant bleeding events (CRBEs). The latter is considered more applicable to real-world clinical practice. NCB was also assessed by center time in therapeutic range (cTTR – the mean TTR of all warfarin patients in each center).

Results: The narrow NCB (1) was similar between dabigatran and warfarin (HR 1.05, 95% confidence interval [CI]: 0.75–1.46). For the broader NCB (2), a statistically significant difference was evident favoring dabigatran over warfarin (HR 0.73, 95% CI: 0.59–0.91).

Stratification of the NCB by cTTR quintiles demonstrated that the positive benefit of dabigatran over warfarin was preserved when comparing to warfarin patients with a good INR control.

Conclusion: In the assessment of real-world net clinical benefit in the prevention of secondary VTE, dabigatran was superior to warfarin, irrespective of INR control in the warfarin patients.

Table. Net clinical benefit for dabigatran versus warfarin in pooled analyses of RE-MEDY™ Dabigatran (N=1430) n (%) Warfarin (N=1426) n (%) HR (95% CI) p value for superiority Narrow: Composite cardiovascular endpoint* and MBEs (NCB 1) 72 (5.0) 69 (4.8) 1.05 (0.75–1.46) 0.7818 Broad: Composite cardiovascular endpoint*, MBEs and CRBEs (NCB 2) 136 (9.5) 183 (12.8) 0.73 (0.59, 0.91) 0.0058

*Nonfatal recurrent venous thromboembolism (VTE), nonfatal myocardial infarction (MI), nonfatal stroke, nonfatal systemic embolism, all-cause death.

Disclosures

Schulman: Boehringer Ingelheim: Consultancy, Honoraria, Research Funding; Bayer HealthCare: Consultancy, Honoraria, Research Funding. Eriksson:Boehringer Ingelheim: Consultancy; BMS: Consultancy; Pfizer: Consultancy. Kakkar:Boehringer Ingelheim: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Daiichi: Consultancy, Honoraria, Research Funding; Bayer: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Eisai: Consultancy, Honoraria, Research Funding. Kearon:Bayer Healthcare: Consultancy; Boehringer Ingelheim (Canada): Consultancy. Schellong:Boehringer Ingelheim: advisory boards Other, Consultancy, Honoraria; Bayer Healthcare: advisory boards, advisory boards Other, Consultancy, Honoraria; Daiichi Sankyo: advisory boards, advisory boards Other, Honoraria; BMS/Pfizer: Honoraria. Feuring:Boehringer Ingelheim: Employment. Hantel:Boehringer Ingelheim: Employment. Kreuzer:Boehringer Ingelheim: Employment. Goldhaber:Boehringer Ingelheim: Consultancy; Daiichi: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Pfizer: Consultancy; Portola: Consultancy; Sanofi-Aventis: Consultancy.