This randomized clinical trial will examine the frequency of treatment with ketamine in patients with treatment-resistant depression TRD without psychosis.
Randomized, parallel-group trial comparing two dosing regimens of ketamine (0.5 mg/kg IV): six infusions every other day over 12 days versus two active infusions (days 1 and 7) with four saline placebos.
Primary population: adults 30–65 with treatment-resistant major depressive disorder without psychosis; key exclusions include bipolar disorder, psychosis, imminent suicide risk, unstable medical disease, and recent substance abuse.
Six ketamine injections (0.5 mg/kg) every other day over 12 days (days 1,3,5,7,9,11).
Days 1,3,5,7,9,11
Two active ketamine injections (days 1 and 7) and four placebo (saline) injections (days 3,5,9,11) over 12 days.
Saline placebo