Cost comparison of continued anticoagulation with rivaroxaban versus placebo based on the 1-year EINSTEIN-Extension trial efficacy and safety results

Abstract

Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI] = –$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.

Keywords:

• Anticoagulants
• cost comparison model
• economic analysis
• extended treatment
• rivaroxaban
• venous thromboembolism

Transparency

Declaration of funding

This research was funded by Janssen Scientific Affairs, LLC, Raritan, NJ, USA.

Declaration of financial/other relationships

PSW has received research funding from BMS/Pfizer; has participated on advisory boards for Bayer Healthcare; has acted as a consultant to Janssen Scientific Affairs, LLC; and has served on a writing committee for Itreas. AWAL is an employee of Bayer Pharma AG. FL, PL, DL, and YX are employees of Groupe d’analyse, Ltée., a consulting company that has received research grants from Janssen Scientific Affairs, LLC. VA, CC, MD, and JS are employees of Janssen Scientific Affairs, LLC. BL and LH are employees of Janssen Research & Development, LLC. JME peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Previous presentations

Parts of this study were presented at the QCOR 2017 Scientific Sessions; April 2–3, 2017; Arlington, VA.