Ketamine in treatment-resistant major depression

Randomised, placebo-controlled parallel-group design enrolling 100 participants with treatment-resistant depression to receive a single IV ketamine infusion (0.5 mg/kg over 40 minutes) or 0.9% saline placebo.

Primary outcome is change in HAMD-17 scores during the first seven days after infusion compared with baseline; secondary measures include quality-of-life (15-D), HAMD/Melancholia Scale, and SCL-90.