Intravenous arketamine for treatment-resistant depression: open-label pilot study

Eur Arch Psychiatry Clin Neurosci. 2021 Apr;271(3):577-582. doi: 10.1007/s00406-020-01110-5. Epub 2020 Feb 20.


We aimed to analyze the efficacy and safety of arketamine, the R(-)-enantiomer of ketamine, for treatment-resistant depression (TRD) in humans. Open-label pilot trial, seven subjects with TRD received a single intravenous infusion of arketamine (0.5 mg/kg); primary outcome was change in Montgomery-Åsberg Depression Rating Scale (MADRS) 24 h after. Mean MADRS dropped from 30.7 before infusion to 10.4 after one day, a mean difference of 20.3 points [CI 95% 13.6-27.0; p < 0.001]; dissociation was nearly absent. Arketamine might produce fast-onset and sustained antidepressant effects in humans with favorable safety profile, like previously reported with animals; further controlled-trials are needed.

Keywords: (R)-Ketamine; Arketamine; Ketamine; Major depressive disorder; Rapid-acting antidepressant; Treatment-resistant depression.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Antidepressive Agents / administration & dosage
  • Antidepressive Agents / adverse effects
  • Antidepressive Agents / pharmacology*
  • Depressive Disorder, Major / drug therapy*
  • Depressive Disorder, Treatment-Resistant / drug therapy*
  • Female
  • Humans
  • Infusions, Intravenous
  • Ketamine / administration & dosage
  • Ketamine / adverse effects
  • Ketamine / pharmacology*
  • Middle Aged
  • Outcome Assessment, Health Care*
  • Pilot Projects
  • Psychiatric Status Rating Scales
  • Remission Induction
  • Severity of Illness Index


  • Antidepressive Agents
  • Ketamine