Trial PaperDepressive DisordersTreatment-Resistant Depression (TRD)Anxiety DisordersHeadache Disorders (Cluster & Migraine)Safety & Risk ManagementChronic PainKetamine

A Double-Blind, Randomized, Placebo-Controlled, Dose-Frequency Study of Intravenous Ketamine in Patients With Treatment-Resistant Depression

This multicenter, double-blind, randomised, placebo-controlled study (n=67) investigated the antidepressant effects of ketamine (35mg/70kg) in relation to the dose frequency administered to patients with depression (TRD). Results indicated that both a twice-weekly and thrice-weekly administration regimen maintained antidepressant efficacy over 15 days.

Authors

  • Gerard Sanacora
  • James Murrough
  • William Drevets

Published

American Journal of Psychiatry
individual Study

Abstract

Objective

Ketamine, an N-methyl-D-aspartate glutamate receptor antagonist, has demonstrated a rapid-onset antidepressant effect in patients with treatment-resistant depression. This study evaluated the efficacy of twice- and thrice-weekly intravenous administration of ketamine in sustaining initial antidepressant effects in patients with treatment-resistant depression.

Method

In a multicenter, double-blind study, adults (ages 18-64 years) with treatment-resistant depression were randomized to receive either intravenous ketamine (0.5 mg/kg of body weight) or intravenous placebo, administered over 40 minutes, either two or three times weekly, for up to 4 weeks. Patients who discontinued double-blind treatment after at least 2 weeks for lack of efficacy could enter an optional 2-week open-label phase to receive ketamine with the same frequency as in the double-blind phase. The primary outcome measure was change from baseline to day 15 in total score on the Montgomery-Åsberg Depression Rating Scale (MADRS).

Results

In total, 67 (45 women) of 68 randomized patients received treatment. In the twice-weekly dosing groups, the mean change in MADRS score at day 15 was −18.4 (SD=12.0) for ketamine and −5.7 (SD=10.2) for placebo; in the thrice-weekly groups, it was −17.7 (SD=7.3) for ketamine and −3.1 (SD=5.7) for placebo. Similar observations were noted for ketamine during the open-label phase (twice-weekly, −12.2 [SD=12.8] on day 4; thrice-weekly, −14.0 [SD=12.5] on day 5). Both regimens were generally well tolerated. Headache, anxiety, dissociation, nausea, and dizziness were the most common (≥20%) treatment-emergent adverse events. Dissociative symptoms occurred transiently and attenuated with repeated dosing.

Conclusions

Twice-weekly and thrice-weekly administration of ketamine at 0.5 mg/kg similarly maintained antidepressant efficacy over 15 days.

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Study Details

References (2)

Papers cited by this study that are also in Blossom

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Berman, R. M., Cappiello, A., Anand, A. et al. · Biological Psychiatry (2000)

Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial

Murrough, J. W., Iosifescu, D. V., Chang, L. C. et al. · American Journal of Psychiatry (2013)

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