| E.1 Medical condition or disease under investigation | 
| E.1.1 | Medical condition(s) being investigated | 
| Post-operative atrial fibrillation (POAF) |  | 
| E.1.1.1 | Medical condition in easily understood language | 
| Prevention of post-operative atrial fibrillation |  | 
| E.1.1.2 | Therapeutic area | Diseases [C] - Cardiovascular Diseases [C14] | 
| MedDRA Classification | 
| E.1.2 Medical condition or disease under investigation | 
| 
| E.1.2 | Version | 20.0 |  
| E.1.2 | Level | PT |  
| E.1.2 | Classification code | 10003658 |  
| E.1.2 | Term | Atrial fibrillation |  
| E.1.2 | System Organ Class | 10007541 - Cardiac disorders |  | 
| E.1.3 | Condition being studied is a rare disease | No | 
| E.2 Objective of the trial | 
| E.2.1 | Main objective of the trial | 
| To compare the efficacy of AGN-151607 with placebo to prevent post-operative atrial fibrillation (POAF) in participants who are undergoing open chest cardiac surgery |  | 
| E.2.2 | Secondary objectives of the trial | 
| - To compare the efficacy of AGN-151607 with placebo to reduce AF burden in participants who are undergoing open-chest cardiac surgery - To compare the efficacy of AGN-151607 with placebo to prevent POAF using alternative definitions for AF in participants who are undergoing open-chest cardiac surgery
 - To compare the safety of AGN-151607 with placebo in participants undergoing open-chest cardiac surgery
 
 |  | 
| E.2.3 | Trial contains a sub-study | No | 
| E.3 | Principal inclusion criteria | 
| - 55 to 90 years of age, inclusive, at the time of signing the informed consent; - scheduled to undergo open-chest cardiac surgery (includes: coronary artery bypass graft [CABG] and/or valve repair/replacement);
 - in sinus rhythm for the last 48 hours prior to surgery (prior history of paroxysmal AF is acceptable);
 - willing to wear an electrocardiogram (ECG) patch for 30 days post-surgery and for 7 days after each study visit.
 |  | 
| E.4 | Principal exclusion criteria | 
| - any medical condition that may put the participant at increased risk with exposure to botulinum toxin type A, including diagnosed muscular dystrophy (eg, Duchenne’s muscular dystrophy), myasthenia gravis, Eaton-Lambert syndrome, amyotrophic lateral sclerosis, mitochondrial disease, or any other significant disease which might interfere with neuromuscular function; - participants with presence or history of any of the following within 3 months prior to the Day 1 visit that may indicate a vulnerable respiratory state per the investigator’s clinical judgment: aspiration pneumonia, lower respiratory tract infections, uncontrolled asthma, severe chronic obstructive pulmonary disease or otherwise compromised respiratory function;
 - permanent/persistent AF;
 - has a known allergy or sensitivity to any botulinum toxin type A preparation;
 - has a known allergy or sensitivity to medical adhesive (eg, ECG patch adhesive; hydrogel based adhesive); severe (> 55mm) atrial enlargement; left ventricular ejection fraction (LVEF) < 25%;
 - presence or history of symptomatic atrioventricular block > 1st degree within the last 30 days;
 - prior or concomitant therapy with Class I or III antiarrhythmic drugs unless proper washout was documented;
 - botulinum toxin type A (of any serotype) use within 6 months of randomization;
 - has been immunized for any botulinum toxin type A serotype as determined by participant medical history;
 - preoperative need for inotropes/vasopressors or intra-aortic balloon pump;
 - prior cardiac surgery;
 - history of ablation for AF;
 - planned ablation procedure for AF at the time of surgery;
 - emergency surgery;
 - impaired prognosis defined as EuroSCORE II greater than 7% perioperative mortality.
 |  | 
| E.5 End points | 
| E.5.1 | Primary end point(s) | 
| Percentage of participants with at least 1 continuous atrial fibrillation (AF) episode ≥ 30 seconds during the first 30 days post surgery |  | 
| E.5.1.1 | Timepoint(s) of evaluation of this end point | 
| within the first 30 days post surgery |  | 
| E.5.2 | Secondary end point(s) | 
| - Percentage of time spent in AF (AF burden) during the first 30 days post surgery - Percentage of participants with at least 1 event of symptomatic AF during the first 30 days post surgery
 - Time to first occurrence of AF during the first 30 days post surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 2 minutes during the first 30 days post-surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 5 minutes during the first 30 days post-surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 30 minutes during the first 30 days post-surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 1 hour during the first 30 days post surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 4 hours during the first 30 days post surgery
 - Percentage of participants with at least 1 continuous AF episode ≥ 24 hours during the first 30 days post surgery
 - Adverse events (AEs), physical examination, clinical laboratory tests, vital signs, electrocardiogram (ECGs), pulmonary function
 - Potential immunogenicity response
 
 
 |  | 
| E.5.2.1 | Timepoint(s) of evaluation of this end point | 
| within the first 30 days post surgery |  | 
| E.6 and E.7 Scope of the trial | 
| E.6 | Scope of the trial | 
| E.6.1 | Diagnosis | No | 
| E.6.2 | Prophylaxis | No | 
| E.6.3 | Therapy | No | 
| E.6.4 | Safety | Yes | 
| E.6.5 | Efficacy | Yes | 
| E.6.6 | Pharmacokinetic | No | 
| E.6.7 | Pharmacodynamic | No | 
| E.6.8 | Bioequivalence | No | 
| E.6.9 | Dose response | Yes | 
| E.6.10 | Pharmacogenetic | No | 
| E.6.11 | Pharmacogenomic | No | 
| E.6.12 | Pharmacoeconomic | No | 
| E.6.13 | Others | No | 
| E.7 | Trial type and phase | 
| E.7.1 | Human pharmacology (Phase I) | No | 
| E.7.1.1 | First administration to humans | No | 
| E.7.1.2 | Bioequivalence study | No | 
| E.7.1.3 | Other | No | 
| E.7.1.3.1 | Other trial type description |  | 
| E.7.2 | Therapeutic exploratory (Phase II) | Yes | 
| E.7.3 | Therapeutic confirmatory (Phase III) | No | 
| E.7.4 | Therapeutic use (Phase IV) | No | 
| E.8 Design of the trial | 
| E.8.1 | Controlled | Yes | 
| E.8.1.1 | Randomised | Yes | 
| E.8.1.2 | Open | No | 
| E.8.1.3 | Single blind | No | 
| E.8.1.4 | Double blind | Yes | 
| E.8.1.5 | Parallel group | Yes | 
| E.8.1.6 | Cross over | No | 
| E.8.1.7 | Other | No | 
| E.8.2 | Comparator of controlled trial | 
| E.8.2.1 | Other medicinal product(s) | No | 
| E.8.2.2 | Placebo | Yes | 
| E.8.2.3 | Other | No | 
| E.8.2.4 | Number of treatment arms in the trial | 3 | 
| E.8.3 | The trial involves single site in the Member State concerned | Yes | 
| E.8.4 | The trial involves multiple sites in the Member State concerned | No | 
| E.8.5 | The trial involves multiple Member States | Yes | 
| E.8.5.1 | Number of sites anticipated in the EEA | 11 | 
| E.8.6 Trial involving sites outside the EEA | 
| E.8.6.1 | Trial being conducted both within and outside the EEA | Yes | 
| E.8.6.2 | Trial being conducted completely outside of the EEA | No | 
| E.8.6.3 | If E.8.6.1 or E.8.6.2 are Yes, specify the regions in which trial sites are planned | 
| Canada |  
| United States |  
| Austria |  
| Germany |  
| Italy |  
| Sweden |  
| United Kingdom |  
| Netherlands |  
| Spain |  | 
| E.8.7 | Trial has a data monitoring committee | Yes | 
| E.8.8 | Definition of the end of the trial and justification where it is not the last
                        visit of the last subject undergoing the trial |  | 
| E.8.9 Initial estimate of the duration of the trial | 
| E.8.9.1 | In the Member State concerned years | 3 | 
| E.8.9.1 | In the Member State concerned months | 11 | 
| E.8.9.1 | In the Member State concerned days | 0 | 
| E.8.9.2 | In all countries concerned by the trial years | 3 | 
| E.8.9.2 | In all countries concerned by the trial months | 11 | 
| E.8.9.2 | In all countries concerned by the trial days | 0 |