Online news media reporting of ketamine as a treatment for depression from 2000 to 2017

Study protocol for Ketamine as an adjunctive therapy for major depression (2): a randomised controlled trial (KARMA-Dep [2])

BACKGROUND

Depression is a common psychiatric disorder and a leading cause of disability worldwide. Conventional monoaminergic antidepressants have limited efficacy and take weeks to exert a therapeutic effect. Single infusions of subanaesthetic doses of ketamine exhibit rapid antidepressant action but effects are transient and relapse is common. One potential strategy for increasing ketamine's antidepressant efficacy and/or prolonging its therapeutic benefit may be serial infusions. There is limited evidence on the efficacy and safety of repeated ketamine infusions against an active comparator.

METHODS

This protocol describes an ongoing pragmatic, randomised, controlled, parallel-group, patient- and rater-blind, superiority trial. Eligible adult inpatients with a confirmed DSM-5 diagnosis of a major depressive episode (unipolar or bipolar) are randomly allocated in a 1:1 ratio to a course of up to eight infusions of ketamine or midazolam twice-weekly over four weeks. The primary objective is to assess the efficacy of serial adjunctive ketamine infusions versus active comparator midazolam by measuring Montgomery-Åsberg Depression Rating Scale score difference between arms from before the first infusion to 24 h after the final infusion, supplemented by a 95% confidence interval. To facilitate generalisability of results, the trial takes place under "real world" conditions with both groups continuing to receive regular inpatient care including treatment-as-usual pharmacotherapy, nursing care, and psychological and other therapies during the randomised treatment phase and regular outpatient care thereafter. Participants are monitored for relapse during a 24-week follow-up after the end of the randomised phase. Secondary objectives of the trial are to assess: response and remission rates at the end of randomised phase; relapse status during the 24-week follow-up after the end of the randomised phase; the safety and tolerability of repeated ketamine infusions regarding psychotomimetic and other psychiatric side effects, cognitive side effects, as well as withdrawal symptoms, haemodynamic stability, neurological, urological, and other physical side effects; and quality of life and cost-effectiveness.

DISCUSSION

There is an unmet clinical need for rapidly-acting novel antidepressants. This trial will provide efficacy, safety and health economic data on serial ketamine infusions and thus help inform clinical practice on the potential role of this treatment in the management of depression.

TRIAL REGISTRATION

EudraCT 2019-003109-92. Registered 2 October 2019.

CLINICALTRIALS

gov NCT04939649. Registered 25 June 2021.

Is approving esketamine as an antidepressant for treatment resistant depression associated with recreational use and risk perception of ketamine? Results from a longitudinal and cross-sectional survey in nightlife attendees

BACKGROUND

Esketamine was licensed for use in treatment resistant depression by the European Medicines Agency in December 2019. It is unclear whether this new approval has lowered the risk perception of recreational ketamine use. This is important given a recent increase in recreational ketamine use.

METHODS

This study expanded on an existing longitudinal online study of the nightlife scene, by adding an additional longitudinal assessment as well as a new cross-sectional sample. Participants had to be aged 18-34 years, reside in the UK and have attended at least 6 electronic music events in the past year. The likelihood of increasing recreational ketamine use due to the approval, attitudes towards and risk perception of medical ketamine use and experiences resulting from recreational ketamine use were collected after the approval. Changes in ketamine use and frequency were assessed longitudinally before and after the approval.

RESULTS

The overall sample size was 2415: 414 longitudinal (57% retention rate) and 2001 new cross-sectional participants. The majority indicated no change in their likelihood of using recreational ketamine due to the approval of esketamine (87%). Longitudinal participants did not indicate an increase in past 12 month use or frequency after the approval. Only one-third of participants reported being aware of the approval. Participants previously aware showed greater overall support for medical use of ketamine than participants previously unaware of the change. However, an equally high risk was assigned to the recreational use of ketamine in both groups. Ketamine users indicated both increases as well as decreases in depression and anxiety as a result of ketamine use.

CONCLUSION

The introduction of esketamine as an antidepressant was not associated with a change in the risk perception of recreational ketamine use in most participants, nor was it longitudinally associated with increased use. Potential negative effects of recreational ketamine use on mental health, as users in this sample reported, should be clearly communicated when discussing the benefits of (es-) ketamine in a therapeutic context.

Holding on or letting go? Patient experiences of control, context, and care in oral esketamine treatment for treatment-resistant depression: A qualitative study

BACKGROUND

Ketamine and its enantiomer esketamine represent promising new treatments for treatment-resistant depression (TRD). Esketamine induces acute, transient psychoactive effects. How patients perceive esketamine treatment, and which conditions facilitate optimal outcomes, remains poorly understood. Understanding patient perspectives on these phenomena is important to identify unmet needs, which can be used to improve (es)ketamine treatments.

AIMS

To explore the perspectives of TRD patients participating in "off label" oral esketamine treatment.

MATERIALS AND METHODS

In-depth interviews were conducted with 17 patients (11 women) after a six-week, twice-weekly esketamine treatment program, and subsequently after six months of at-home use. Interviews explored participants' perspectives, expectations, and experiences with esketamine treatment. Audio interviews were transcribed verbatim and analysed following an Interpretative Phenomenological Analysis (IPA) framework.

RESULTS

Key themes included overwhelming experiences; inadequate preparation; letting go of control; mood states influencing session experiences; presence and emotional support, and supportive settings. Patients' attempts to let go and give into vs. attempts to maintain control over occasionally overwhelming experiences was a central theme. Multiple factors influenced patients' ability to give into the experience and appeared to impact their mood and anxiety about future sessions, including level of preparation and education, physical and emotional support, and setting during the session.

CONCLUSION

Better preparation beforehand, an optimized treatment setting, and emotional and psychological support during (es)ketamine sessions can help patients to "let go" and may lead to better quality of care and outcomes. Recommendations to improve quality of patient care in (es)ketamine treatment are provided, including suggestions for the training of nurses and other support staff.

Ketamine for Depression: Advances in Clinical Treatment, Rapid Antidepressant Mechanisms of Action, and a Contrast with Serotonergic Psychedelics

The approval of ketamine for treatment-resistant depression has created a model for a novel class of rapid-acting glutamatergic antidepressants. Recent research into other novel rapid-acting antidepressants - most notably serotonergic psychedelics (SPs) - has also proven promising. Presently, the mechanisms of action of these substances are under investigation to improve these novel treatments, which also exhibit considerable side effects such as dissociation. This chapter lays out the historical development of ketamine as an antidepressant, outlines its efficacy and safety profile, reviews the evidence for ketamine's molecular mechanism of action, and compares it to the proposed mechanism of SPs. The evidence suggests that although ketamine and SPs act on distinct primary targets, both may lead to rapid restoration of synaptic deficits and downstream network reconfiguration. In both classes of drugs, a glutamate surge activates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) throughput and increases in brain-derived neurotrophic factor (BDNF) levels. Taken together, these novel antidepressant mechanisms may serve as a framework to explain the rapid and sustained antidepressant effects of ketamine and may be crucial for developing new rapid-acting antidepressants with an improved side effect profile.