A Study to Evaluate Adverse Events and Effectiveness of OnabotulinumtoxinA in Participants Undergoing Open Abdominal Ventral Hernia Repair for the Achievement of Primary Fascial Closure Without the Use of Component Separation Technique

Inclusion Criteria: * Participant is in good health as determined by medical history, vital signs, and investigator's judgment, including no known active pandemic infection. * Body Mass Index (BMI) at screening is \<= 40 kg/m2. * Participant meets the following disease activity criteria: * Intact abdominal wall muscles (defined as no prior dissection to the lateral abdominal wall complex) based on screening CT scan. * Midline ventral hernia requiring surgical repair, at least 6 cm, and not more than 18 cm in transverse defect width at the widest part of the of the hernia defect, as assessed on CT scan by the investigator. * Any portion of the ventral hernia does not extend \> 3 cm into the M1 subxiphoid zone or into the M5 zone using the 2009 classification by the European Hernia Society. * No history of prior onlay hernia mesh wider than rectus. * No hernia with loss of domain \>20% as determined by the investigator, using Sabbagh method. Exclusion Criteria: * Presence of a medical condition that may put the participant at increased risk with exposure to onabotulinumtoxinA, including diagnosed muscular dystrophy (e.g., 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. * Presence or history of any of the following within 3 months prior to the randomization visit that may indicate a vulnerable respiratory state per the investigator's clinical judgment, for example, aspiration pneumonia, lower respiratory tract infections, uncontrolled asthma, severe chronic obstructive pulmonary disease, or otherwise compromised respiratory function. * History of ongoing or anticipated need to perform progressive preoperative pneumoperitoneum or other tissue expansion technique for repair of ventral hernia. * Planned ostomy reversal, panniculectomy bariatric procedure, or vascular procedure requiring anticoagulants during the study. * History of abdominal or hernia repair surgery requiring hospitalization within 6 months prior to screening. * History of a contraindication to BOTOX and/or hypersensitivity reactions to BOTOX.