Not yet recruitingPHASE2INTERVENTIONAL

A Study to Test How Well BAY 3670549 Works and How Safe it is in Patients With Atrial Fibrillation

This study is looking into a new medicine, BAY 3670549, for people who have an irregular heartbeat called atrial fibrillation (AF). The main goal is to find out how well this new medicine works, how safe it is, and if people can take it without too many side effects. We'll compare it to a dummy treatment (placebo) in people whose AF needs a procedure called electrical cardioversion to get their heart back to a normal rhythm. Participants will receive the study medicine through a drip. We'll then see if their heart rhythm becomes normal on its own, potentially avoiding the need for electrical cardioversion. This research could help find new ways to treat AF. The study could last up to two months for each person.

At a glance

Status

Not yet recruiting

Phase

PHASE2

Sponsor

Bayer

Enrolment target

360

Start

19 Jun 2026

Estimated completion

16 May 2030

Atrial Fibrillation

What is this study about?

This research is about a heart condition called atrial fibrillation (AF), where the heart beats irregularly. For some people with AF, a procedure called electrical cardioversion is used to reset the heart's rhythm back to normal. This study is testing a new medicine, BAY 3670549, to see if it can help the heart return to a normal rhythm on its own, possibly reducing the need for electrical cardioversion.

The study aims to understand several things about BAY 3670549: how effective it is in bringing the heart back to a normal steady rhythm, how safe it is, if people can take it without too many unwanted effects, and how the body processes the medication. To do this, new participants, including yourself, will be randomly given either BAY 3670549 or a dummy treatment (called a placebo) through a drip. A placebo looks like the real medicine but contains no active drug, helping us understand the true effects of the new medicine.

After receiving the treatment, doctors will closely watch to see if your heart rhythm returns to normal by itself. If it doesn't, you can still have the electrical cardioversion procedure as originally planned. The information we gather from this study, such as how many people's hearts return to normal rhythm without the procedure and how long that takes, could help develop a new treatment option for people with AF in the future.

Key takeaways

This study tests a new medicine for an irregular heartbeat (AF).
It aims to see if the medicine can help the heart return to a normal rhythm on its own.
The medicine is compared to a dummy treatment (placebo).
Participation involves receiving the study treatment and being monitored.
The study could last up to two months for each person.
This research might lead to new AF treatment options.

Who may be eligible?

To join this study, you need to be an adult aged between 18 and 85 years old. Your heart condition, atrial fibrillation (AF), must be stable, meaning it's not an emergency and you are not very unwell. Your AF episode should have started at least 3 hours ago but no more than 30 days ago. You must also be scheduled to have electrical cardioversion for your AF.

Before taking part, you'll need to have had any necessary scans for blood clots in your heart and be on blood-thinning medication if required, as per standard local guidelines. Your body mass index (BMI) should also be between 18 and 39.9. If you can become pregnant, you or your partner will need to use effective contraception as outlined by the study rules.

There are also reasons why you might not be able to join. For example, if you have another irregular heartbeat called atrial flutter, or if there's a medical reason why you shouldn't have electrical cardioversion on the planned day. You also can't participate if you have a very enlarged left chamber of your heart (left atrium) or if you've had a major heart event in the last six months.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 18 and 85 years old?
Do you have atrial fibrillation (AF) that started between 3 hours and 30 days ago?
Are you scheduled to have electrical cardioversion for your AF?
Do you have a Body Mass Index (BMI) between 18 and 39.9?
Are you able to use reliable contraception if needed?
Have you not had a very enlarged heart chamber in the last 6 months?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you'll first need to sign a consent form, showing you understand what's involved. You will then receive a single dose of either the study medicine (BAY 3670549) or a dummy treatment (placebo) through a drip into your arm. Doctors will then observe you closely to see if your heart's rhythm returns to normal on its own.

If your heart rhythm doesn't go back to normal by itself, you'll still be able to have the electrical cardioversion as planned. You will also need to wear a small device that records your heart's electrical activity (an ECG) at home, and you'll have some follow-up phone calls. The total time you'd be involved in the study is up to two months.

Potential risks and benefits

Taking part in a study like this could potentially offer benefits, such as having your heart rhythm return to normal without electrical cardioversion, and you would be contributing to medical research that might help others with AF in the future. However, there are potential risks, including side effects from the study medicine or the possibility that it might not work for you. As with any medical procedure, there are also risks associated with electrical cardioversion if it's still needed. You have the right to leave the study at any time, for any reason, without it affecting your usual medical care.

Locations (28)

UCSF Advanced Heart Failure Comprehensive Care Center
Verified postcode
San Francisco, United States
UCHealth University of Colorado Hospital - Cardiology
Verified postcode
Aurora, United States
Massachusetts General Hospital - Cardiology
Verified postcode
Boston, United States
Henry Ford Hospital - Cardiology
Verified postcode
Detroit, United States
Duke University Hospital - Cardiology
Verified postcode
Durham, United States
CHRISTUS Trinity | Mother Frances Louis and Peaches Owen Heart Hospital - Electrophysiology Clinic
Verified postcode
Tyler, United States
Jessa Ziekenhuis | Hartcentrum Hasselt
Verified postcode
Hasselt, Belgium
UZ Leuven Gasthuisberg - Cardiology diseases department
Verified postcode
Leuven, Belgium
AZ Delta | Clinical Trial Center - Cardiology
Verified postcode
Roeselare, Belgium
University Multiprofile Hospital For Active Treatment Sveti Georgi' - EAD Department of Intensive Cardiology"
Verified postcode
Plovdiv, Bulgaria
Multiprofile Hospital for Active Treatment Knyaginya Klementina Sofia EAD | Cardiology Department
Verified postcode
Sofia, Bulgaria
University Hospital for Active Treatment Tsaritsa Joanna - ISUL | Cardiology Clinic
Verified postcode
Sofia, Bulgaria

Common questions

What is atrial fibrillation (AF)?

AF is a common heart condition that causes an irregular and often fast heart rate.

What is electrical cardioversion?

It's a procedure where a controlled electrical shock is given to the chest to restore a normal heart rhythm.

What is a placebo?

A placebo is a 'dummy' treatment that looks like the real medicine but doesn't contain any active drug. It helps researchers see if the real medicine actually works.

How long will I be in the study?

The study could last up to two months for each person who takes part.

Can I leave the study if I change my mind?

Yes, you can choose to leave the study at any time, for any reason, and it won't affect your medical care.

How to find out more

Bayer Clinical Trials Contact

clinical-trials-contact@bayer.com 18888422937 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.