Clinical trial Recruiting at 9 sites Phase 2 Interventional Ages 18 to 85

BAY 3670549 in Atrial Fibrillation: Does it help restore normal rhythm after AF episode?

Official title: A Placebo-controlled, Parallel-group, Double Blind, Randomized, Multi-cohort Phase 2 Study to Investigate Efficacy, Safety, Tolerability, Pharmacodynamics and Pharmacokinetics of BAY 3670549 in Adult Participants With Atrial Fibrillation.

Run by Bayer · NCT07625215 · Data updated 2026-11-12

This study tests BAY 3670549 against a placebo in adults with atrial fibrillation who need electrical cardioversion to see if it helps restore normal heart rhythm and how safe it is.

Quick facts

PhasePhase 2
Study typeInterventional
Ages18 Years to 85 Years
SexAll
Enrollment360 (estimated)
SponsorBayer
Industry-sponsored
Locations30 sites (San Francisco, California and 29 other locations)
StatusRecruiting
StartedSeptember 1, 2026
Main results expectedMay 16, 2030
Study endsMay 16, 2030
Registry record updatedOctober 20, 2026
Trial IDNCT07625215 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults aged 18–85 with a current AF episode lasting 3 hours to 30 days, stable enough for elective cardioversion and meeting anticoagulation and imaging prerequisites.

Probably not a fit

Patients not responding to BAY 3670549 or who experience adverse safety effects may not benefit.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a Phase 2, randomized, placebo-controlled trial evaluating BAY 3670549 in adults with atrial fibrillation. Participants receive a single IV infusion of BAY 3670549 or placebo and are monitored to see if their heart rhythm returns to normal without or with subsequent electrical cardioversion. The study examines the proportion achieving restoration of normal rhythm, time to rhythm restoration, safety, tolerability, and pharmacokinetics. Eligible participants are 18 to 85 years old, hemodynamically stable, with AF lasting 3 hours to 30 days, and needing cardioversion under standard guidelines. Investigational sites include UCSF, UCHealth, and Massachusetts General Hospital.

Why it matters

Potential benefit: If successful, BAY 3670549 could increase the chance and speed of returning to a normal heart rhythm for patients with AF undergoing cardioversion.

How similar studies have gone: Previous similar approaches have shown signal in rhythm restoration with targeted therapies, but this specific agent and design are novel in this context.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Participant must be 18 to 85 years of age inclusive, at the time of signing the informed consent.
* Participant is hemodynamically stable and does not require emergency cardioversion, as determined by the investigator.
* Participant has a current episode of atrial fibrillation (AF) ongoing for at least 3 hours and no more than 30 days at the time of randomization.
* Participant has an indication for electrical cardioversion of AF, as determined by the investigator according to standard clinical practice and national/institutional guidelines.
* At randomization, successful initiation and achievement of therapeutic levels of anticoagulation therapy, as well as completion of imaging evaluation for left atrial thrombi, as appropriate for the duration of the AF episode and risk for the participant according to national guideline and institution-specific routine practice.
* BMI within range \[18 - 39.9\] kg/m2.
* Contraceptive use by participants or participant partners should be consistent with the study protocol and local regulations regarding the methods of contraception for those participating in clinical studies.
* Signed informed consent which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol
* Willing and able to comply with the receipt, home use, and return of the continuous ECG recording device, as well as with the participation in scheduled telephone follow-up assessments.

Exclusion Criteria:

* Current atrial flutter (AFL) or combined AF/AFL
* Contraindication for electrical cardioversion on planned treatment day
* Documented severely dilated left atrium (left atrial diameter, LAD \>5 cm) measured by any modality within the 6 months prior to screening; if several values are available, the most recent one shall be reported. If left atrium diameter was not measured in the last 6 months or a major cardiovascular event occurred within the last 6 months, a new measurement must be done at screening
* Unsuccessful conversion of current AF episode (pharmacologically or electrically)
* Known severe valvular heart disease (e.g., severe mitral regurgitation, severe aortic stenosis)
* Patients with NYHA Class ≥ III heart failure, or with active management of acute heart failure decompensation on treatment day.
* History within the preceding 3 months prior to randomization of any of the following events, or any other significant cardiovascular event as judged by the investigator:

  * Stroke
  * Myocardial infarction
  * Unstable angina pectoris or other signs of myocardial ischemia
  * Cardiac surgery
  * Transcatheter valve replacement
  * Percutaneous coronary intervention (PCI)
  * Coronary artery bypass graft (CABG) or other revascularization procedure
* Severe renal impairment, i.e., estimated glomerular filtration rate (eGFR) \<30 mL/min/1.73m² (using CKD-EPI formula) or requiring dialysis
* Severe hepatic impairment, i.e. Child Pugh Class C
* Use of anti-arrhythmic class I or III drugs within 5 half-lives before study drug administration (oral amiodarone in the previous 3 months)
* Hypertension with SBP ≥ 180 mmHg or hypotension (SBP \< 90 mmHg) at randomization (based on the second BP measurement)
* Stressor-associated AF, i.e., in the setting of an acute and reversible stressor (e.g., cardiac surgery, myocarditis, endocarditis, sepsis, pneumonia, etc.). This includes ablation procedure within the preceding one month prior to randomization.

Where it's running

  • Henry Ford Hospital - Cardiology
    Detroit, Michigan, United States
    Recruiting
  • UZ Leuven Gasthuisberg - Cardiology diseases department
    Leuven, Flemish Brabant, Belgium
    Recruiting
  • University Hospital for Active Treatment Tsaritsa Joanna - ISUL | Cardiology Clinic
    Sofia, Sofia City Province, Bulgaria
    Recruiting
  • Multiprofile Hospital for Active Treatment Dr. Stefan Cherkezov | Base 1 - Cardiology Department
    Veliko Tarnovo, Veliko Tarnovo Province, Bulgaria
    Recruiting
  • Klinikum Altenburger Land GmbH-Klinik für Kardiologie, Pneumologie und Internistische Intensivmedizin
    Altenburg, Thuringia, Germany
    Recruiting
  • Semmelweis Egyetem, Varosmajori Sziv- és Ergyogyaszati Klinika
    Budapest, Hungary
    Recruiting
Show 24 more locations
  • Ente Ecclesiastico Ospedale Generale Regionale Miulli - Cardiologia e UTIC
    Acquaviva delle Fonti, Apulia, Italy
    Recruiting
  • Centro Cardiologico Monzino S.p.A. - UO Scompenso e Cardiologia Clinica
    Milan, Lombardy, Italy
    Recruiting
  • Samodzielny Publiczny Specjalistyczny Szpital Zachodni im. sw. Jana Pawla II
    Grodzisk Mazowiecki, Masovian Voivodeship, Poland
    Recruiting
  • UCSF Advanced Heart Failure Comprehensive Care Center
    San Francisco, California, United States
    Withdrawn
  • UCHealth University of Colorado Hospital - Cardiology
    Aurora, Colorado, United States
    Not yet recruiting
  • Massachusetts General Hospital - Cardiology
    Boston, Massachusetts, United States
    Not yet recruiting
  • M Health Fairview Heart Clinic - Maplewood
    Maplewood, Minnesota, United States
    Withdrawn
  • Duke University Hospital - Cardiology
    Durham, North Carolina, United States
    Not yet recruiting
  • Texas Health Heart and Vascular Specialists - Fort Worth
    Fort Worth, Texas, United States
    Not yet recruiting
  • CHRISTUS Trinity | Mother Frances Louis and Peaches Owen Heart Hospital - Electrophysiology Clinic
    Tyler, Texas, United States
    Not yet recruiting
  • Jessa Ziekenhuis | Hartcentrum Hasselt
    Hasselt, Limburg, Belgium
    Not yet recruiting
  • AZ Delta | Clinical Trial Center - Cardiology
    Roeselare, West Flanders, Belgium
    Not yet recruiting
  • University Multiprofile Hospital For Active Treatment Sveti Georgi' - EAD Department of Intensive Cardiology"
    Plovdiv, Plovdiv Province, Bulgaria
    Not yet recruiting
  • Multiprofile Hospital for Active Treatment Knyaginya Klementina Sofia EAD | Cardiology Department
    Sofia, Sofia City Province, Bulgaria
    Not yet recruiting
  • Medizinische Hochschule Hannover|Kardiologie und Angiologie
    Hanover, Lower Saxony, Germany
    Not yet recruiting
  • Herz-und Diabeteszentrum NRW|Elektrophysiologie/Rhythmologie
    Bad Oeynhausen, North Rhine-Westphalia, Germany
    Not yet recruiting
  • Tolna Vármegyei Balassa János Kórház - I. Belgyógyászati Osztály: Kardiológia, Nefrológia
    Szekszárd, Tolna County, Hungary
    Not yet recruiting
  • Azienda Ospedaliero-Universitaria Policlinico Umberto I - Malattie Cardiovascolari
    Rome, Lazio, Italy
    Not yet recruiting
  • Azienda Ospedaliero Universitaria Delle Marche - Clinica di Cardiologia e Aritmologia
    Torrette, The Marches, Italy
    Not yet recruiting
  • Maastricht UMC
    Maastricht, Limburg, Netherlands
    Not yet recruiting
  • Universitair Medisch Centrum Groningen
    Groningen, Netherlands
    Not yet recruiting
  • American Heart of Poland S.A. - MCSN, PAKS w Chrzanowie - Oddział Intensywnej Opieki Kardiologicznej
    Chrzanów, Lesser Poland Voivodeship, Poland
    Not yet recruiting
  • USK nr 4 w Lublinie - Kliniczny Odd. Kardiologii, Reh. Kardio., Ch. Wew. z Pododdzialem Intensywnej Opieki Kardio.
    Lublin, Lublin Voivodeship, Poland
    Not yet recruiting
  • American Heart of Poland S.A. - PAKS Centrum Kardiologii i Kardiochirurgii w Bielsku-Białej - Oddział Kardiologii
    Bielsko-Biala, Silesian Voivodeship, Poland
    Not yet recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.