Association of Bleeding Severity with Mortality with in-Hospital and Extended Thromboprophylaxis in the Medically Ill in the Magellan Trial
Authors: Spyropoulos Alex C. , Raskob Gary E. , Cohen Alexander T , Ageno Walter , Weitz Jeffrey I. , Spiro Theodore E. , Lu Wentao , Lipardi Concetta , Barnathan Elliot S. 
Published: November 2019

Background: Venous thromboembolism (VTE) is common after hospitalization in acutely ill medical patients, yet extended thromboprophylaxis has not been widely implemented due to concerns about bleeding. The MAGELLAN study (NCT00571649) evaluated whether rivaroxaban (10 mg QD for 35±4 days) compared with enoxaparin (40 mg QD for 10±4 days) followed by placebo could prevent asymptomatic deep vein thrombosis, symptomatic VTE, and VTE-related death. Through Day 35, rivaroxaban was superior to enoxaparin/placebo in the modified intent-to-treat population (4.4% vs 5.7%, RR 0.77, 95%CI, 0.62 to 0.96, p=0.02), but there was an increase in clinically relevant bleeding, the composite of major and non-major clinically relevant (NMCR) bleeding (4.1% vs 1,7%, RR 2.5, 95%CI 1.85-3.25, p<0.001). Although major bleeding has been associated with increased mortality, the relationship between NMCR bleeding and all-cause mortality (ACM) is not established. We hypothesized that subjects in the MAGELLAN trial with major bleeding but not those with NMCR bleeding, would be at an increased risk of ACM irrespective of treatment group.
Methods: We evaluated all bleeding events in subjects taking at least one dose of study drug from randomization until 2 days after the last dose (safety population) and their association with ACM through the Day 90 visit in 3 mutually exclusive groups: (1) subjects with no major or NMCR bleeding; (2) subjects whose first event was NMCR bleeding; and (3) subjects whose first event was major bleeding. Subjects only developing minimal or trivial bleeding were grouped with those who had no clinically relevant bleeding. Using a Cox proportional hazards model that included the bleeding group variable and baseline covariates significantly associated with ACM at p<0.05 (age, BMI, history of cancer, history of anemia, inflammatory disease, acute ischemic stroke, and acute respiratory insufficiency), we compared the risk of ACM in subjects with and without bleeding events.
Results: The incidence of ACM for subjects who had NMCR bleeding was numerically higher but not significantly increased compared with subjects with no bleeding (20/176, 11.4% vs 468/7763, 6.0%, HR 1.41 95%CI 0.88, 2.25, p=0.151), while subjects with major bleeding were at a significantly increased risk of death (28/59, 47.5% vs 468/7763, 6.0%, HR 7.74 95%CI 5.16, 11.59, p<0.0001). Results of landmark analyses from the first bleeding event or end of treatment + 2 days to ACM for the three groups are displayed (Figure).
Limitations: This analysis was post hoc and may have been underpowered to detect differences in ACM associated with NMCR bleeding.
Conclusion: Major bleeding was associated with a significantly increased risk of ACM but NMCR bleeding was not. This suggests that a modest increase in NMCR bleeding associated with extended thromboprophylaxis with rivaroxaban may be acceptable to prevent VTE. Strategies to better select patients at lower risk of bleeding may improve the benefit risk profile of extended thromboprophylaxis with rivaroxaban.

Disclosures
Spyropoulos: Daiichi Sankyo: Consultancy; Boehringer Ingelheim: Consultancy, Research Funding; Portola: Consultancy; Bayer Healthcare: Consultancy; ATLAS (Colorado Prevention Center): Consultancy; Janssen R&D, LLC: Consultancy. Raskob:Janssen R&D, LLC: Consultancy, Honoraria; Novartis: Consultancy; Tetherex: Consultancy; Daiichi Sankyo: Consultancy, Honoraria; Anthos: Consultancy; Boehringer Ingelheim: Consultancy; Pfizer: Consultancy, Honoraria; Portola: Consultancy; Bayer Healthcare: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Eli Lilly: Consultancy. Cohen:Boston Scientific: Consultancy; CSL Behring: Consultancy; GlaxoSmithKline: Consultancy, Speakers Bureau; Daiichi-Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Boehringer-Ingelheim: Consultancy, Speakers Bureau; GLG: Consultancy; AbbVie: Consultancy; ACI Clinical: Consultancy; Aspen: Consultancy, Speakers Bureau; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Guidepoint Global: Consultancy; Johnson and Johnson: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Leo Pharma: Consultancy; Medscape: Consultancy, Speakers Bureau; McKinsey: Consultancy; Navigant: Consultancy; ONO: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Portola: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy; Temasek Capital: Consultancy; TRN: Consultancy; UK Government Health Select Committee: Other: advised the UK Government Health Select Committee, the all-party working group on thrombosis, the Department of Health, and the NHS, on the prevention of VTE; Lifeblood: Other: advisor to Lifeblood: the thrombosis charity and is the founder of the European educational charity the Coalition to Prevent Venous Thromboembolism. Ageno:Boehringer Ingelheim: Membership on an entity's Board of Directors or advisory committees, Other: conference and travel support; Bayer: Membership on an entity's Board of Directors or advisory committees, Other: research support,travel support ; BMS Pfizer: Other: travel support; Aspen: Membership on an entity's Board of Directors or advisory committees, Other: travel support; Portola: Membership on an entity's Board of Directors or advisory committees, Other: travel support; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees, Other: travel support; Sanofi: Membership on an entity's Board of Directors or advisory committees, Other: travel support. Weitz:Janssen R&D, LLC: Consultancy; Bayer Healthcare: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Daiichi-Sankyo: Consultancy, Honoraria; Ionis: Consultancy, Honoraria; Merck: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Portola: Consultancy, Honoraria. Spiro:Bayer U.S. LLC: Employment, Equity Ownership. Lu:Janssen R&D, LLC: Employment, Equity Ownership. Lipardi:Janssen Research and Develompent: Employment, Equity Ownership. Barnathan:Janssen Research and Development LLC: Employment, Equity Ownership.

OffLabel Disclosure:
Rivaroxaban is a Factor Xa inhibitor. It is currently under review by FDA for approval as thromboprophylaxis in acutely ill medical patients at risk for venous thromboembolism.