Atrial Fibrillation (AF)Phase 4BRACE-AFibNCT07904507
A Comparison of Beta-blockers and Calcium Channel Blockers in Atrial Fibrillation
A Phase 4 study testing Experimental intervention in people with Atrial Fibrillation (AF), run by University Hospital, Basel, Switzerland at 1 site in Switzerland.
Trial summary
Beta-blockers are generally prescribed for the treatment of atrial fibrillation. Their purpose is to slow the heart rate and thereby reduce the workload on the heart. However, beta-blockers can affect patients' quality of life, for example by reducing physical performance or causing fatigue in daily life. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Atrial Fibrillation (AF)
- What is being tested?
- Experimental intervention
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 266 participants
- Where
- 1 siteSwitzerland
- Study dates
- Nov 2026to Oct 2029
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Documented AF
- Currently on a stable regimen of BB for at least three weeks
- Informed consent as documented by signature
Who cannot join
- Left ventricular ejection fraction (LVEF) <40%
- Severe valvular heart disease
- Uncontrolled hypertension defined as systolic BP > 180 mmHg
- AV block Type II, AV block type III
- Severe bradycardia, defined as a resting heart rate <40 bpm on ECG
- Currently on a NDCC (Diltiazem or Verapamil)
Show all 18Show fewer
- Concomitant rhythm-controlling medication (antiarrhythmic drugs Vaughan Williams classification I and III)
- Currently on Ivabradine, Digoxin, Clonidine, Pimozide, Dihydroergotamine, Nifedipine, Lomitapide
- History of atrio-ventricular node ablation
- Implanted pacemaker or implantable cardioverter defibrillator (ICD) with a right-ventricular pacing burden >40%
- Previous pulmonary vein isolation (PVI) or electric cardioversion within 90 days prior to study enrolment
- Established infiltrative myocardial disease, e.g. amyloidosis, constrictive pericarditis, myocarditis, hypertrophic cardiomyopathy
- End-stage renal disease, estimated glomerular filtration rate (eGFR) <15 ml/min/1.73 m2
- Pregnant or breastfeeding women, or women of childbearing potential who do not use a highly effective form of birth control
- Expected life expectancy < 6months
- Drug or alcohol abuse
- Inability to understand and sign study information and patient informed consent
- Both women and men will be enrolled, and sex-specific differences in treatment effects will be examined in a subgroup analysis. No vulnerable populations will be included. All participants are capable of judgment.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Switzerland1 site
University Hospital Basel
Basel, Canton of Basel-City, 4031
Patrick Badertscher, PD Dr. med., 61 556 58 23 ext. +41, patrick.badertscher@usb.ch
Stefanie Aeschbacher, PhD, 61 328 67 72 ext. +41, stefanie.aeschbacher@usb.ch
About this study
Official title: BRACE-AFib: Beta-blocker Replacement and Calcium Channel Blockers Evaluation in Atrial Fibrillation
Beta-blockers are generally prescribed for the treatment of atrial fibrillation. Their purpose is to slow the heart rate and thereby reduce the workload on the heart. However, beta-blockers can affect patients' quality of life, for example by reducing physical performance or causing fatigue in daily life.
In this study, we aim to determine whether calcium channel blockers can improve the treatment of atrial fibrillation and have a positive impact on the quality of life of patients with atrial fibrillation compared with beta-blockers. We will also investigate how calcium channel blockers affect the physical exercise capacity. In addition, we will monitor potential side effects of both medications and explore whether there are any differences between women and men over the course of the study.
Both study medications, the calcium channel blocker diltiazem and the beta-blocker bisoprolol, are approved by authorities and are recommended by the European Society of Cardiology for rate control in atrial fibrillation.
Read the detailed description
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia. Many AF patients present with a rapid ventricular response resulting in a high heart rate (HR). In these patients, it is important to lower the HR. To achieve rate control, several pharmacological agents are available, but beta-blockers (BB) are predominantly used. There is little evidence supporting the preference for BB. Side effects of BB such as fatigue, dizziness, and effort intolerance are widely known. Non-dihydropyridine calcium channel blockers (NDCC) represent an alternative for rate control and might be associated with better quality of life (QoL) than BB in AF patients. This study aims to investigate the impact on the QoL of AF patients who are currently on BB therapy and are switching to NDCC. Both men and women affected by AF and its complications will be enrolled in the study.
If this study can show an advantage of NDCC over BB in AF patients, a paradigm shift in the treatment of AF could take place. This could mean an easily implementable potential therapeutic advantage at no supplementary cost for patients and the health care system. Given the very common use of BB in AF patients, the negative impact of this drug on QoL could affect thousands of patients.
The investigational medicinal product (IMP) is diltiazem, a NDCC. Diltiazem belongs to the benzothiazepine class and exerts its pharmacological effect through inhibition of L-type calcium channels in atrioventricular nodal tissue, resulting in negative dromotropic effects and effective ventricular rate control in AF. Diltiazem is approved by the authorities and recommended by current guidelines as an alternative to BB for rate control in AF.
In the present study, diltiazem is administered orally in a prolonged-release formulation at daily doses of 90 mg, 180 mg, or 360 mg, corresponding to low, normal, or high dose categories. The comparator is bisoprolol, a β1-selective beta-adrenergic receptor blocker. BB are the most frequently prescribed agents for rate control in AF and represent the current standard of care. Bisoprolol is administered orally at daily doses of 2.5 mg, 5 mg, or 10 mg, reflecting standard clinical practice.
Patient representatives have been involved in developing our research from the beginning. Their insights have guided our approach to ensure the study addresses real concerns faced by patients affected by AF.
- Conditions
- Atrial Fibrillation (AF)
- Being tested
- Experimental intervention, Control Intervention
- Keywords
- Atrial Fibrillation, Quality of Life, Bisoprolol, Diltiazem, Calcium Channel Blockers, Arrhythmias, Cardiac, Clinical Trial, Phase IV, Beta-Blocker
- Medical subject headings
- Atrial Fibrillation, Arrhythmias, Cardiac
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Experimental interventionDrug
Study participants randomized in the experimental intervention group will receive Non-dihydropyridine calcium channel blockers (NDCC) Diltiazem retard for 90 days. Depending on the dosage of the beta-blocker treatment of these patients at baseline, three different dosage options will be used (low, normal, high). Diltiazem capsules of 90mg will be provided, meaning that patients with the low dosage will take one capsule a day (morning), patients with the normal dosage two capsules a day (morning and evening) and patients with the high dosage four capsules a day (2x morning and 2x evening). Based on previous data, we assume that most patients will use the low or normal dosage. The medication Diltiazem 90mg will be over-encapsulated, packed and labelled by a pharmacy specialist.
Control InterventionDrug
Study patients will receive the beta-blocker (BB) Bisoprolol for 90 days. Depending on the dosage of the BB treatment of these patients at baseline, three different dosage options will be used (low, normal high). Low dosage of Bisoprolol is corresponding to 2.5mg, normal dosage to 5mg and high dosage to 10mg/day. Bisoprolol capsules of 2.5mg will be provided, meaning that patients with the low dosage will take one capsule a day (morning), patients with the normal dosage two capsules a day (morning and evening) and patients with the high dosage four capsules (2x morning and 2x evening). The medication Bisoprolol will be over-encapsulated, packed and labelled by a pharmacy specialist.
| Study group | Role | What they receive |
|---|---|---|
| Diltiazem | Experimental | 133 patients are randomized to the experimental intervention and treated with the non-dihydropyridine calcium channel blocker (NDCC) Diltiazem. Receives: Drug: Experimental intervention |
| Bisoprolol | Active comparator | 133 patients are randomized to the control arm and treated with the beta-blocker Bisoprolol. Receives: Drug: Control Intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Atrial-Fibrillation-related Quality of Life
Change in Atrial-Fibrillation-related Quality of Life between Non-dihydropyridine calcium channel blockers (NDCC) versus continuation of beta-blockers (BB) from baseline to 3 months in patients with Atrial-Fibrillation.
The primary outcome uses the AFEQT questionnaire:
The AFEQT 20-item questionnaire is a validated, AF-specific QoL tool. It assesses 4 domains: symptoms, daily activities, treatment concerns, and treatment satisfaction. The overall AFEQT score is calculated using the first 3 domains and ranges from 0 = worst to 100 = best QoL. Additionally, for each domain of interest, there is a corresponding subscale score: symptoms, daily activities, treatment concerns, and treatment satisfaction subscale scores. Each subscale ranges from 0 = worst to 100 = best QoL and is scored separately. The AFEQT questionnaire will be done at baseline before the intake of the first study drug and after three months of intervention.
Measured: From baseline to 3 months
Secondary outcomes (4)
NT-proBNP
Change in NT-proBNP levels measured at baseline and after 3 months.
NT-proBNP is released into the circulation in response to myocardial cell stretch. This biomarker is commonly used to evaluate the degree of heart failure in cardiac patients. Non-fasting blood samples will be taken at baseline before randomization and at the final study visit (4.7ml each). NT-proBNP levels will be measured in the laboratory of the respective study site by using an electrochemiluminescence immunoassay (Elecsys, Roche Diagnostics, Switzerland). Furthermore, if patients provide consent, additional blood samples (serum, plasma and whole blood) will be taken, processed, frozen and stored at -80°C, according to the ethical guidelines concerning biobanking, at the Cardiovascular Research Institute Basel. These samples will be used for future genetic analyses and for the assessment of emerging biomarkers of interest in this context.
Measured: At Baseline and after 3 Months
6-minute walking test (6MWT) distance
Change in 6MWT distance assessed at baseline and after 3 months
The 6MWT is a simple test which does not require expensive equipment or advanced training for technicians. The test involves asking the patient to walk the longest distance possible in a set interval of 6 minutes, through a walking course (corridor) preferably 30 meters long. The result of the 6MWT will be entered in the CRF as the distance in meters. In this context, other variables will be assessed, including the Borg Scale after the test and information on whether the test was done with a walking aid or must be terminated earlier. The 6MWT will be done at baseline before randomization and after 3 months of intervention.
Measured: At baseline and after 3 months
Peak flow measurement
Change in peak flow measured at baseline and at the study end visit after 90 days of study intervention. The patient will perform the test in a standing position. Study personnel will instruct the patient to inhale as deeply as possible and then exhale as forcefully and rapidly as they can. The measurement will be repeated three times, and the results of all three attempts will be recorded in the study database.
Measured: At baseline and after 3 months
Hierarchical composite endpoint comprising
A hierarchical win ratio will be calculated comparing participants between treatment groups using the following pre-specified hierarchy (in order of priority), all assessed as change from baseline to 3 months:
- AF-related QoL
- 6MWT distance
- NT-proBNP
Measured: Baseline to 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Oct 2026
- Study startNov 2026 (estimated)
- Primary completionOct 2029 (estimated)
- Study completionOct 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Atrial Fibrillation (AF)Studies of the same condition, open and under way.
- More trials run by University Hospital, Basel, SwitzerlandThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized, double-blind, multicenter, controlled, superiority trial
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 266 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Hospital, Basel, Switzerland
- Sponsor type
- University, hospital or other
- Collaborators
- Swiss National Science Foundation, Schweizerische Herzstiftung, Freiwillige Akademische Gesellschaft Basel, Clinical Trial Unit, University Hospital Basel, Switzerland
- Responsible party
- Sponsor
- Investigators
- Patrick Badertscher, PD Dr. med., Principal investigator, University Hospital, Basel, Switzerland
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07904507
- Sponsor's protocol ID
- 2026-00823; kt24Kuehne2
- Acronym
- BRACE-AFib
- Status last verified
- Oct 2026
- First submitted
- 22 Oct 2026
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- BRACE-AFib: Beta-blocker Replacement and Calcium Channel Blockers Evaluation in Atrial Fibrillation
- ClinicalTrials.gov ID
- NCT07904507
- Acronym / sponsor ID
- BRACE-AFib / 2026-00823; kt24Kuehne2
- Conditions
- Atrial Fibrillation (AF)
- Keywords
- Atrial Fibrillation, Quality of Life, Bisoprolol, Diltiazem, Calcium Channel Blockers, Arrhythmias, Cardiac, Clinical Trial, Phase IV, Beta-Blocker
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 266 participants (estimated)
- Lead sponsor
- University Hospital, Basel, SwitzerlandUniversity, hospital or other
- Collaborators
- Swiss National Science Foundation, Schweizerische Herzstiftung, Freiwillige Akademische Gesellschaft Basel, Clinical Trial Unit, University Hospital Basel, Switzerland
- Study start
- Nov 2026 (estimated)
- Primary completion
- Oct 2029 (estimated)
- Study completion
- Oct 2029 (estimated)
- First posted
- 29 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Beta-blockers are generally prescribed for the treatment of atrial fibrillation. Their purpose is to slow the heart rate and thereby reduce the workload on the heart. However, beta-blockers can affect patients' quality of life, for example by reducing physical performance or causing fatigue in daily life.
In this study, we aim to determine whether calcium channel blockers can improve the treatment of atrial fibrillation and have a positive impact on the quality of life of patients with atrial fibrillation compared with beta-blockers. We will also investigate how calcium channel blockers affect the physical exercise capacity. In addition, we will monitor potential side effects of both medications and explore whether there are any differences between women and men over the course of the study.
Both study medications, the calcium channel blocker diltiazem and the beta-blocker bisoprolol, are approved by authorities and are recommended by the European Society of Cardiology for rate control in atrial fibrillation.
Detailed description
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia. Many AF patients present with a rapid ventricular response resulting in a high heart rate (HR). In these patients, it is important to lower the HR. To achieve rate control, several pharmacological agents are available, but beta-blockers (BB) are predominantly used. There is little evidence supporting the preference for BB. Side effects of BB such as fatigue, dizziness, and effort intolerance are widely known. Non-dihydropyridine calcium channel blockers (NDCC) represent an alternative for rate control and might be associated with better quality of life (QoL) than BB in AF patients. This study aims to investigate the impact on the QoL of AF patients who are currently on BB therapy and are switching to NDCC. Both men and women affected by AF and its complications will be enrolled in the study.
If this study can show an advantage of NDCC over BB in AF patients, a paradigm shift in the treatment of AF could take place. This could mean an easily implementable potential therapeutic advantage at no supplementary cost for patients and the health care system. Given the very common use of BB in AF patients, the negative impact of this drug on QoL could affect thousands of patients.
The investigational medicinal product (IMP) is diltiazem, a NDCC. Diltiazem belongs to the benzothiazepine class and exerts its pharmacological effect through inhibition of L-type calcium channels in atrioventricular nodal tissue, resulting in negative dromotropic effects and effective ventricular rate control in AF. Diltiazem is approved by the authorities and recommended by current guidelines as an alternative to BB for rate control in AF.
In the present study, diltiazem is administered orally in a prolonged-release formulation at daily doses of 90 mg, 180 mg, or 360 mg, corresponding to low, normal, or high dose categories. The comparator is bisoprolol, a β1-selective beta-adrenergic receptor blocker. BB are the most frequently prescribed agents for rate control in AF and represent the current standard of care. Bisoprolol is administered orally at daily doses of 2.5 mg, 5 mg, or 10 mg, reflecting standard clinical practice.
Patient representatives have been involved in developing our research from the beginning. Their insights have guided our approach to ensure the study addresses real concerns faced by patients affected by AF.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, investigator)
- Number of arms
- 2
- Model description
- Randomized, double-blind, multicenter, controlled, superiority trial
| Arm | Type | Receives |
|---|---|---|
| Diltiazem | Experimental | Drug: Experimental intervention133 patients are randomized to the experimental intervention and treated with the non-dihydropyridine calcium channel blocker (NDCC) Diltiazem. |
| Bisoprolol | Active comparator | Drug: Control Intervention133 patients are randomized to the control arm and treated with the beta-blocker Bisoprolol. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Documented AF
- Currently on a stable regimen of BB for at least three weeks
- Informed consent as documented by signature
Key exclusion criteria (18 listed)
- Left ventricular ejection fraction (LVEF) <40%
- Severe valvular heart disease
- Uncontrolled hypertension defined as systolic BP > 180 mmHg
- AV block Type II, AV block type III
- Severe bradycardia, defined as a resting heart rate <40 bpm on ECG
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Experimental interventionStudy participants randomized in the experimental intervention group will receive Non-dihydropyridine calcium channel blockers (NDCC) Diltiazem retard for 90 days. Depending on the dosage of the beta-blocker treatment of these patients at baseline, three different dosage options will be used (low, normal, high). Diltiazem capsules of 90mg will be provided, meaning that patients with the low dosage will take one capsule a day (morning), patients with the normal dosage two capsules a day (morning and evening) and patients with the high dosage four capsules a day (2x morning and 2x evening). Based on previous data, we assume that most patients will use the low or normal dosage. The medication Diltiazem 90mg will be over-encapsulated, packed and labelled by a pharmacy specialist. | Drug | Diltiazem |
| Control InterventionStudy patients will receive the beta-blocker (BB) Bisoprolol for 90 days. Depending on the dosage of the BB treatment of these patients at baseline, three different dosage options will be used (low, normal high). Low dosage of Bisoprolol is corresponding to 2.5mg, normal dosage to 5mg and high dosage to 10mg/day. Bisoprolol capsules of 2.5mg will be provided, meaning that patients with the low dosage will take one capsule a day (morning), patients with the normal dosage two capsules a day (morning and evening) and patients with the high dosage four capsules (2x morning and 2x evening). The medication Bisoprolol will be over-encapsulated, packed and labelled by a pharmacy specialist. | Drug | Bisoprolol |
Primary outcome
Atrial-Fibrillation-related Quality of Life
Time frame: From baseline to 3 months
Change in Atrial-Fibrillation-related Quality of Life between Non-dihydropyridine calcium channel blockers (NDCC) versus continuation of beta-blockers (BB) from baseline to 3 months in patients with Atrial-Fibrillation. The primary outcome uses the AFEQT questionnaire: The AFEQT 20-item questionnaire is a validated, AF-specific QoL tool. It assesses 4 domains: symptoms, daily activities, treatment concerns, and treatment satisfaction. The overall AFEQT score is calculated using the first 3 domains and ranges from 0 = worst to 100 = best QoL. Additionally, for each domain of interest, there is a corresponding subscale score: symptoms, daily activities, treatment concerns, and treatment satisfaction subscale scores. Each subscale ranges from 0 = worst to 100 = best QoL and is scored separately. The AFEQT questionnaire will be done at baseline before the intake of the first study drug and after three months of intervention.
4 secondary outcomes
NT-proBNP
Time frame: At Baseline and after 3 Months
6-minute walking test (6MWT) distance
Time frame: At baseline and after 3 months
Peak flow measurement
Time frame: At baseline and after 3 months
Hierarchical composite endpoint comprising
Time frame: Baseline to 3 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
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ATRIAL APPENDAGE CLOSURE for ATRIAL FIBRILLATION, Atrial Fibrillation (AF)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Patrick Badertscher, PD Dr. med. principal investigator
University Hospital, Basel, Switzerland
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Experimental intervention in people with Atrial Fibrillation (AF), run by University Hospital, Basel, Switzerland at 1 site in Switzerland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 18 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Patrick Badertscher, PD Dr. med. (61 556 58 23 ext. +41, patrick.badertscher@usb.ch), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Atrial-Fibrillation-related Quality of Life (time frame: From baseline to 3 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.