Modulation of the antidepressant effects of ketamine by the mTORC1 inhibitor rapamycin
Chadi G. Abdallah, Lynnette A. Averill, Ralitza Gueorguieva, Selin Goktas, P. Purohit, Mohini Ranganathan, Mohamed Sherif, K. Ahn, Deepak C. D’Souza, R. Formica, Steven M. Southwick, Ronald S. Duman, Gerard Sanacora, John H. Krystal
Neuropsychopharmacology February 24, 2020 DOI: 10.1038/s41386-020-0644-9 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Double-blind Peer reviewed |
|---|---|
| Sample size | 20 |
| Population | Patients suffering a major depressive episode |
| Interventions | Rapamycin Ketamine |
| Dose | 6 mg rapamycin oral, 0.5 mg/kg ketamine intravenous |
| Duration | 2-week follow-up after each treatment day |
| Topics | Esketamine Ketamine |
| Citations | 181 |
| Key findings | Rapamycin pretreatment did not block ketamine's 24-hour antidepressant effects but prolonged them over two weeks, with higher response and remission rates compared to placebo. |
Abstract
Twenty-four hours after administration, ketamine exerts rapid and robust antidepressant effects that are thought to be mediated by activation of the mechanistic target of rapamycin complex 1 (mTORC1). To test this hypothesis, depressed patients were pretreated with rapamycin, an mTORC1 inhibitor, prior to receiving ketamine. Twenty patients suffering a major depressive episode were randomized to pretreatment with oral rapamycin (6 mg) or placebo 2 h prior to the intravenous administration of ketamine 0.5 mg/kg in a double-blind cross-over design with treatment days separated by at least 2 weeks. Depression severity was assessed using Montgomery–Åsberg Depression Rating Scale (MADRS). Rapamycin pretreatment did not alter the antidepressant effects of ketamine at the 24-h timepoint. Over the subsequent 2-weeks, we found a significant treatment by time interaction ( F (8,245) = 2.02, p = 0.04), suggesting a prolongation of the antidepressant effects of ketamine by rapamycin. Two weeks following ketamine administration, we found higher response (41%) and remission rates (29%) following rapamycin + ketamine compared to placebo + ketamine (13%, p = 0.04, and 7%, p = 0.003, respectively). In summary, single dose rapamycin pretreatment failed to block the antidepressant effects of ketamine, but it prolonged ketamine’s antidepressant effects. This observation raises questions about the role of systemic vs. local blockade of mTORC1 in the antidepressant effects of ketamine, provides preliminary evidence that rapamycin may extend the benefits of ketamine, and thereby potentially sheds light on mechanisms that contribute to depression relapse after ketamine administration.
Comparable studies
Other randomized controlled trials on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Healthy human subjects recruited from the community | 1994 | Randomized controlled trial | n = 19 |
| Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial Patients with treatment-resistant major depression experiencing a major depressive episode | 2013 | Randomized controlled trial | n = 73 |
| Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine Patients undergoing major abdominal surgery | 2005 | Randomized controlled trial | n = 75 |
| Efficacy of Intravenous Ketamine for Treatment of Chronic Posttraumatic Stress Disorder Patients with chronic PTSD related to a range of trauma exposures | 2014 | Randomized controlled trial | n = 41 |
| Ketamine-Induced Deficits in Auditory and Visual Context-Dependent Processing in Healthy Volunteers Healthy volunteers | 2000 | Single-blind placebo-controlled study | n = 20 |
Citations in the library
Cited by 75
- Synthesizing the Evidence for Ketamine and Esketamine in Treatment-Resistant Depression: An International Expert Opinion on the Available Evidence and Implementation American Journal of Psychiatry March 17, 2021
- Hallucinogens in Mental Health: Preclinical and Clinical Studies on LSD, Psilocybin, MDMA, and Ketamine Journal of Neuroscience November 30, 2020
- Neuroplasticity as a convergent mechanism of ketamine and classical psychedelics TIPS - Trends in Pharmacological Sciences September 24, 2021
- Ketamine: A tale of two enantiomers Journal of Psychopharmacology November 6, 2020
- Molecular mechanisms underlying the antidepressant actions of arketamine: beyond the NMDA receptor Molecular Psychiatry May 7, 2021
and 70 more in the library
Cites 14
- A Randomized Trial of an N-methyl-D-aspartate Antagonist in Treatment-Resistant Major Depression Archives of General Psychiatry August 1, 2006
- mTOR-Dependent Synapse Formation Underlies the Rapid Antidepressant Effects of NMDA Antagonists Science August 19, 2010
- Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial American Journal of Psychiatry August 28, 2013
- A Randomized Add-on Trial of an N-methyl-D-aspartate Antagonist in Treatment-Resistant Bipolar Depression Archives of General Psychiatry August 1, 2010
- A Double-Blind, Randomized, Placebo-Controlled, Dose-Frequency Study of Intravenous Ketamine in Patients With Treatment-Resistant Depression American Journal of Psychiatry April 8, 2016
and 9 more in the library