Ketamine In Depression - Intensive Care Unit Trial (KID-ICU): A Phase II Randomized, Double-Blind, Placebo-Controlled Multicenter Study of Ketamine Infusion for Depressive Symptoms in Intensive Care Unit Patients

Summary

\*\*Brief Summary\*\* Depressive symptoms are frequent among patients admitted to the intensive care unit (ICU) and may be associated with worse clinical outcomes, reduced participation in care, lower treatment adherence, and increased mortality. Conventional antidepressants, including selective serotonin reuptake inhibitors (SSRIs), have limited utility in this setting because of their delayed onset of action, incomplete efficacy, and potential drug interactions in medically complex patients. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has emerged as a rapid-acting antidepressant when administered at subanesthetic doses. Preliminary evidence suggests that intravenous ketamine may improve mood-related symptoms within a short time frame and may have an acceptable safety profile in selected critically ill patients. The KID-ICU trial (Ketamine In Depression - Intensive Care Unit) is a Phase II randomized, double-blind, placebo-controlled multicenter trial designed to evaluate the efficacy and safety of subanesthetic intravenous ketamine infusions for moderate-to-severe depressive symptoms in adult ICU patients. Eligible participants are adults who have been admitted to the ICU for 6 or more days and have moderate-to-severe depressive symptoms, defined as a Patient Health Questionnaire-9 (PHQ-9) score of 10 or greater. Participants will be randomized in a 1:1 ratio to receive either intravenous ketamine at 0.5 mg/kg, with a maximum dose of 60 mg per day, administered over 40 to 60 minutes on 2 consecutive days, or placebo with normal saline in an identical presentation. The primary efficacy outcome is the change in PHQ-9 score from baseline to Day 30 after the last infusion. Safety outcomes include prespecified hemodynamic, neuropsychiatric, and treatment-discontinuation events during and after infusion. Secondary outcomes include anxiety and depression symptoms assessed with the Hospital Anxiety and Depression Scale (HADS), clinical severity and improvement assessed with Clinical Global Impression scales, intensive care unit and hospital length of stay, and mortality. A total of 50 participants will be enrolled across intensive care unit sites at Hospital Italiano de Buenos Aires. Psychiatric and clinical follow-up will be provided to all participants regardless of treatment assignment.