CLOT Conversations

Which DOAC Bleeds Less? COBRRA Trial Insights for VTE Care with Dr Lana Castellucci

Thrombosis Canada Season 2 Episode 29

Use Left/Right to seek, Home/End to jump to start or end. Hold shift to jump forward or backward.

0:00 | 16:24

Send us Fan Mail

Which DOAC bleeds less in acute VTE?

In this episode, we explore the COBRRA trial comparing apixaban vs rivaroxaban and what it means for clinical practice.

The COBRRA trial provides the first direct, randomized comparison of apixaban and rivaroxaban for the treatment of acute venous thromboembolism (VTE).

In this episode of CLOT Conversations, Dr. Lana Castellucci discusses findings from this landmark study and how they should influence anticoagulant selection.

Key insights include:

  • Apixaban reduced clinically relevant bleeding by more than 50% compared to rivaroxaban
  • Differences in bleeding risk emerged early and persisted over the 3-month treatment period
  • Recurrent VTE and mortality rates were similar between groups
  • Dosing strategies and early treatment phase appear to play a key role

We also explore real-world considerations, including medication adherence, patient preference, and how to approach populations not included in the trial, such as cancer-associated thrombosis and higher body weight.

This episode provides practical, evidence-based guidance for clinicians managing acute DVT and pulmonary embolism.

 Listen now to learn how the COBRRA trial may change your approach to DOAC selection.

Access the publication here:

Castellucci LA, Chen VM, Kovacs MJ, Lazo-Langner A, Greenstreet P, Kahn S, Côté B, Schulman S, De Wit K, Douketis J, Suryanarayan D. Bleeding risk with apixaban vs. rivaroxaban in acute venous thromboembolism. New England Journal of Medicine. 2026 Mar 12;394(11):1051-60.

Support the show

https://thrombosiscanada.ca

Take a look at our healthcare professional and patient resources, videos and publications on thrombosis from the expert members of Thrombosis Canada

Welcome back to CLOT Conversations, where we explore the latest research and clinical insights in thrombosis. I'm David Airdrie, Executive Director of Thrombosis Canada, joined by Dr Maha Othman.

Today we ask:

how do apixaban and rivaroxaban compare in bleeding risk in acute VTE? We’re discussing the COBRRA trial from the New England Journal of Medicine. We’re joined by Dr Lana Castellucci, hematologist and clinician-scientist based in Ottawa. She led the international COBRRA trial comparing apixaban and rivaroxaban in acute VTE. Let’s dive in. What was the motivation for this study? This study was designed after the EINSTEIN and AMPLIFY trials showed differences in bleeding rates. We wanted a direct comparison between apixaban and rivaroxaban. Apixaban reduced clinically relevant bleeding by more than 50 percent. Both major and clinically relevant non-major bleeding were lower with apixaban. Bleeding differences appeared early in treatment. Within the first two to three weeks, curves separated between treatments. This likely reflects higher initial dosing with rivaroxaban. The difference persisted throughout the three-month treatment period. Recurrent VTE rates were similar between groups, around one percent. Mortality was low and comparable. Adherence was slightly higher with rivaroxaban. Likely due to once-daily dosing compared to twice daily apixaban. Differences in pharmacology and dosing likely explain bleeding differences. The trial excluded cancer patients and those over 120 kilograms. Clinicians must consider applicability to those populations. Other studies help guide treatment in cancer-associated thrombosis. Shared decision-making remains essential. Apixaban should be first-line for most acute VTE patients. But patient preference and drug interactions still matter. These findings cannot yet be extrapolated to atrial fibrillation. Ongoing trials will address that question.

Key takeaway:

similar efficacy, but lower bleeding with apixaban. This should guide DOAC selection in clinical practice. Thank you to all collaborators and participants. Thank you for listening to CLOT Conversations.