Study to Assess the Efficacy, Safety, and Tolerability of AVP-786 for the Treatment of Intermittent Explosive Disorder

Inclusion Criteria: * Diagnosis of current Intermittent Explosive Disorder (IED) according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria, as solicited by the Structured Clinical Interview for DSM-5, Clinical Trials Version * At least 3 IED days (at least 1 IED episode each day, as recorded by the participant) per week for the 2 consecutive weeks directly preceding baseline with 70% compliance during that time frame, as assessed by the investigator * Score ≥ 12 on the Life History of Aggression scale at screening * Score ≥ 6 on the Overt Aggression Scale - Modified Total Irritability at screening and baseline * Score ≥ 4 on the modified Clinical Global Impression of Severity for IED at screening and baseline Exclusion Criteria: * Diagnosis of major depressive disorder within 6 months of screening * Significant symptoms of a depressive disorder or a Patient Health Questionnaire-9 score ≥ 10 at screening * Met only the DSM-5 A2 criterion for IED * Lifetime history of schizophrenia, schizoaffective disorder, bipolar disorder, antisocial personality disorder, neurocognitive disorder, or mental retardation (DSM-5 criteria) * Recurrent IED episodes that are better explained by another mental disorder or attributable to another medical condition (e.g., head trauma, Alzheimer's disease) or to the physiological effect of a substance (e.g., a drug of abuse, a medication) (DSM-5 criteria)