Rapid and Longer-Term Antidepressant Effects of Repeated Ketamine Infusions in Treatment-Resistant Major Depression
Biological Psychiatry, 07/31/2012
Clinical Article
Murrough JW et al. – Ketamine was associated with a rapid antidepressant effect in treatment–resistant major depression that was predictive of a sustained effect.
Methods- Participants with TRD (n = 24) underwent a washout of antidepressant medication followed by a series of up to six IV infusions of ketamine (.5 mg/kg) administered open-label three times weekly over a 12-day period.
- Participants meeting response criteria were monitored for relapse for up to 83 days from the last infusion.
- The overall response rate at study end was 70.8%.
- There was a large mean decrease in Montgomery-Asberg Depression Rating Scale score at 2 hours after the first ketamine infusion (18.9 ± 6.6, p < .001), and this decrease was largely sustained for the duration of the infusion period.
- Response at study end was strongly predicted by response at 4 hours (94% sensitive, 71% specific).
- Among responders, median time to relapse after the last ketamine infusion was 18 days.



