PROJECT SUMMARY Rates of suicide have increased dramatically in youths over the past decade, and suicide is now the 2nd leading cause of death for individuals ages 15-24. There are no validated treatments to decrease the risk of adolescent suicidal behavior, and currently available standard treatments are of modest benefit and often take weeks or months to become effective. Hence, there is an urgent need to identify rapid-acting treatments that ameliorate symptoms associated with suicidality and prevent repeat suicidal events. Based on evidence for efficacy of ketamine in reducing symptoms of suicidality in adults, as well as an open label study in adolescents, ketamine appears to be a promising treatment approach for youths with a recent suicidal event. We propose to conduct the first randomized, controlled trial of ketamine in youth with recent suicidal behaviors. All youth will be in treatment in an intensive outpatient program for suicidal adolescents, and will be randomized to intravenous ketamine 0.5mg/kg or midazolam 0.02mg/kg for four infusions over two weeks within +/- ten days of starting IOP. We will also examine implicit cognitive associations using the Death/Suicide Implicit Association Test (IAT). All participants will be followed for 12 weeks to evaluate: 1) reduction in repeat suicide attempts over 12 weeks, 2) reduction in implicit suicidal cognition within the 2-week study treatment period, and 3) reduction in depression and suicidal ideation within the 2-week study period. We will also explore whether reductions in IAT mediates improvement in suicidality over 12 weeks. To date, no study has reported evidence for 1) reduction in repeat suicidal events with ketamine either in adults or in youths (AIM 1), 2) reductions either in implicit cognition (AIM 2) or in symptoms associated with suicidality (AIM 3) in youths, and 3) underlying mechanisms that mediate (AIM 4) the effects of ketamine on suicidality. Innovative features include: 1) it targets repeat suicidal events during a high-risk period in high-risk youths who are typically excluded from clinical trials; 2) is transdiagnostic; 3) seamlessly integrates in current standard of care; and 4) evaluates an intervention that can be delivered at a time and place when there is greatest clinical need, but for which there are no currently developed interventions.

PROJECT NARRATIVE Despite the fact that suicide is the 2nd leading cause of death in adolescents, ages 15-24 years of age, there are no validated treatments to decrease the risk of adolescent suicidal behavior, and currently available standard treatments are of modest benefit and often take weeks or months to become effective. The status quo as it pertains to treatment of youths with recent suicidal events has resulted in frequent repeat suicidal events, marked burden on youths and their caregivers by frequent visits, and prolonged suffering by the delay between initiation of currently available pharmacotherapy and psychotherapy interventions and when they finally become effective. This project aims to examine the efficacy of ketamine, a rapidly acting medication shown to decrease suicidality in adults in as short as hours or days, as opposed to weeks.