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Study on the Effectiveness of Abelacimab for High-Risk Atrial Fibrillation Patients Unsuitable for Oral Anticoagulation

Fast replyInvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying Atrial Fibrillation, a condition where the heart beats irregularly and often rapidly. The study is evaluating a treatment called Abelacimab, which is given as a solution for infusion. The purpose of the study is to determine if Abelacimab is more effective than a placebo in reducing the risk of certain complications, such as ischemic stroke, in patients with atrial fibrillation who cannot take oral blood thinners.

Participants in the study will receive either Abelacimab or a placebo, which is a substance that looks like the treatment but has no active ingredients. The study is designed to be double-blind, meaning neither the participants nor the researchers will know who is receiving the actual treatment or the placebo. This helps ensure that the results are not biased. The study will take place over a period of time, during which participants will be monitored for any occurrences of stroke or other related health events.

The trial aims to provide valuable information on the safety and effectiveness of Abelacimab for patients with atrial fibrillation who are at high risk and cannot use standard oral anticoagulation therapy. By participating in this study, researchers hope to find a new treatment option that could potentially benefit many people with this heart condition.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, you will be asked to provide written informed consent. This means you agree to participate after understanding the details and purpose of the study.

    You will be assessed to ensure you meet the criteria for participation, such as having a diagnosis of atrial fibrillation and being deemed unsuitable for oral anticoagulation therapy.

  2. Step 2

    Randomization

    You will be randomly assigned to one of two groups. One group will receive the study medication, abelacimab, and the other will receive a placebo, which looks like the medication but has no active ingredients.

    This process is double-blind, meaning neither you nor the study team will know which group you are in.

  3. Step 3

    Medication administration

    If you are in the group receiving abelacimab, you will be given a 150 mg/ml solution for infusion. This medication is administered through a subcutaneous injection, which means it is injected under the skin.

    The frequency and duration of the medication administration will be determined by the study protocol, and you will be informed of the schedule.

  4. Step 4

    Regular monitoring

    Throughout the study, you will have regular appointments to monitor your health and the effects of the medication. This may include physical exams, blood tests, and other assessments.

    These appointments are important to ensure your safety and to gather data on the medication's effectiveness.

  5. Step 5

    Completion of the study

    At the end of the study period, you will have a final assessment to evaluate your overall health and any effects of the treatment.

    You will be informed about the next steps and any follow-up care that may be necessary.

Who can join the trial?

9 criteria

  • The patient must be able to understand the study and must have given written permission to participate.
  • The patient must have been diagnosed with Atrial Fibrillation (AF) or atrial flutter, which should be confirmed by an ECG (a test that records the electrical activity of the heart) or a monitor recording.
  • The patient should be between the ages of 65 and 74 with a CHA2DS2VASc score of 4 or higher, or 75 years or older with a CHA2DS2VASc score of 3 or higher. The CHA2DS2VASc score is a tool used to estimate the risk of stroke in patients with AF.
  • The patient must be considered by their doctor to be unsuitable for taking oral anticoagulation (blood-thinning) medication because the risks are greater than the benefits, or the patient does not want to take these medications. This decision should have been made before and not because of this study.
  • The patient must have at least one of the following conditions:
    • Severe renal insufficiency, which means the kidneys are not working well (specifically, a creatinine clearance of less than 30 mL/min, measured by a specific formula).
    • A plan to use aspirin, a P2Y12 inhibitor (a type of medication that prevents blood clots), or another antiplatelet agent every day during the study.
    • A history of bleeding from a critical area, such as the brain, eyes, spine, heart sac, abdomen, joints, or muscles, or major bleeding in the digestive system.
    • Other conditions that increase the risk of bleeding, such as regular use of NSAIDs (non-steroidal anti-inflammatory drugs) three or more times a week, frailty, or a history of frequent falls.
    • The patient must be considered by their doctor to be unsuitable for a procedure called left atrial appendage (LAA) closure or occlusion device, or such a device is not available, or the patient does not want to undergo the procedure. This decision should have been made before and not because of this study.

Who cannot join the trial?

3 criteria

  • Patients with a history of Atrial Fibrillation (a condition where the heart beats irregularly) who are not suitable for oral anticoagulation therapy cannot participate.
  • Patients who are not within the specified age range for the study cannot participate.
  • Patients who belong to a vulnerable population, such as those unable to give consent, cannot participate.
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Investigated drugs

Abelacimab is a medication being studied for its potential to help people with a heart condition called atrial fibrillation, especially those who cannot take standard blood-thinning medications. Atrial fibrillation is a condition where the heart beats irregularly, which can lead to blood clots and increase the risk of stroke. Abelacimab works by targeting specific proteins in the blood to prevent clot formation, which may reduce the risk of stroke or other complications related to blood clots. This study aims to see if abelacimab is more effective than not taking any active medication in preventing strokes in these patients.

What is already known about the treatment

Abelacimab – Abelacimab is administered as an injection and is currently being studied in clinical trials for its potential use in patients with atrial fibrillation who cannot take oral blood thinners. The main goal of this medication is to reduce the risk of stroke or other serious blood clot-related events in these patients. Abelacimab works by targeting specific proteins in the blood that are involved in clot formation, helping to prevent dangerous clots from forming. It is classified as an anticoagulant, which means it helps to keep the blood flowing smoothly by preventing clots.

Investigated diseases

Atrial Fibrillation – Atrial Fibrillation is a heart condition characterized by an irregular and often rapid heart rate. This irregular rhythm can lead to poor blood flow and may cause the heart's upper chambers to quiver instead of contracting effectively. Over time, this can result in blood clots forming in the heart, which can travel to other parts of the body and cause complications such as stroke. The condition may start with brief episodes that become longer and more persistent. It can lead to symptoms like palpitations, shortness of breath, and fatigue. The progression of Atrial Fibrillation can vary, with some individuals experiencing mild symptoms and others having more severe impacts on their daily life.
Trial detailsLast updated 2 Oct 2026
Age65+ yearsPhasePhase IIITrial ID2023-503224-66-00Protocol codeCMAA868A2302(ANT-010Estimated enrolment2 729 patientsSponsorAnthos Therapeutics Inc.

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).