Overview
- Inpatients were randomized to receive up to eight adjunctive infusions over four weeks of either ketamine or the psychoactive comparator midazolam alongside standard care.
- No difference emerged on the primary clinician-rated Montgomery-Åsberg Depression Rating Scale at the end of treatment.
- Patient-reported symptoms on the QIDS-SR-16 also did not differ between groups, and there were no advantages on cognitive, economic, or quality-of-life outcomes.
- Outcomes remained null through a six-month follow-up, with the lead investigator stating that adjunctive ketamine offered no added benefit under rigorous trial conditions.
- Trial leaders emphasized that most patients and raters correctly guessed treatment allocation, highlighting the need to assess blinding success and to conduct further rigorous randomized comparisons.