Intranasal Ketamine in Treatment-Resistant Depression

Randomised, quadruple-blind crossover in 20 participants with treatment-resistant major depressive disorder comparing a single intranasal ketamine dose (up to 50 mg) with intranasal saline.

Primary purpose to evaluate safety and efficacy; eligibility required IDS-C30 thresholds and prior inadequate response to at least one antidepressant. Safety assessed via labs, ECG, and adverse events.