Comparing the Efficacy and Bleeding Risk of Abelacimab vs. Rivaroxaban in Atrial Fibrillation
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Reviewed by Dat Tien Nguyen, B.A, ScM.
Translated by Nhi Phuong Quynh Le, B.A |
Posted on February 12th, 2025
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Atrial fibrillation is the most common form of arrhythmia, characterized by abnormal and rapid atrial contractions. This lack of coordination between the heart chambers creates turbulent blood flow, leading to the aggregation of red blood cells into clots. As a result, patients with atrial fibrillation face a fivefold increased risk of stroke. The condition is currently treated with anticoagulants, such as rivaroxaban. A study funded by Anthos Therapeutics was conducted to compare the effectiveness of abelacimab with the current standard regimen in reducing the risk of cardiovascular complications associated with atrial fibrillation.
The clinical trial involved 1,287 participants aged 55 and older who had been diagnosed with atrial fibrillation. Over 90% of the patients had been treated with anticoagulants for more than 60 days, with two-thirds using direct oral anticoagulants and one-third using vitamin K antagonists. Additionally, around one-quarter of the cohort was using antiplatelet medications, with aspirin being the most commonly used, followed by P2Y12 inhibitors.
The participants were randomly assigned to be treated with either the current standard anticoagulant, rivaroxaban, or abelacimab. The former was administered orally at a daily dose of 20 mg, while two doses of abelacimab - 90 mg or 150 mg, which is delivered subcutaneously once monthly. Abelacimab is an antibody that can bind to and neutralize both the activated and inactivated form of clotting factors XI, which prevent the protein from participating in the clotting cascade.
Given that bleeding is a primary concern with anticoagulant use, the researchers found that abelacimab was associated with a roughly 65% lower risk of bleeding compared to rivaroxaban. Specifically, patients treated with abelacimab had a reduced risk of gastrointestinal bleeding. Additionally, the study showed that abelacimab was equally effective as rivaroxaban in preventing ischemic stroke and systemic embolism. However, the researchers noted that the study size was too small to fully compare the efficacy between the two agents.
The clinical trial involved 1,287 participants aged 55 and older who had been diagnosed with atrial fibrillation. Over 90% of the patients had been treated with anticoagulants for more than 60 days, with two-thirds using direct oral anticoagulants and one-third using vitamin K antagonists. Additionally, around one-quarter of the cohort was using antiplatelet medications, with aspirin being the most commonly used, followed by P2Y12 inhibitors.
The participants were randomly assigned to be treated with either the current standard anticoagulant, rivaroxaban, or abelacimab. The former was administered orally at a daily dose of 20 mg, while two doses of abelacimab - 90 mg or 150 mg, which is delivered subcutaneously once monthly. Abelacimab is an antibody that can bind to and neutralize both the activated and inactivated form of clotting factors XI, which prevent the protein from participating in the clotting cascade.
Given that bleeding is a primary concern with anticoagulant use, the researchers found that abelacimab was associated with a roughly 65% lower risk of bleeding compared to rivaroxaban. Specifically, patients treated with abelacimab had a reduced risk of gastrointestinal bleeding. Additionally, the study showed that abelacimab was equally effective as rivaroxaban in preventing ischemic stroke and systemic embolism. However, the researchers noted that the study size was too small to fully compare the efficacy between the two agents.