The safety and efficacy of Ketamine NMDA receptor blocker as a therapeutic intervention for PTSD review of a randomized clinical trial

The association between ketamine and esketamine with alcohol and substance misuse: Reports to the Food and Drug Administration adverse event reporting system (FAERS)

INTRODUCTION

Ketamine and esketamine have been proven to be effective in treating adults with treatment resistant depression (TRD). Preliminary evidence indicates that, when combined with behavioral and psychological interventions, both agents may offer benefits for individuals with substance use disorder (SUD) and alcohol use disorder (AUD). Notwithstanding, concerns have been raised as to whether either or both agents are associated with abuse and/or gateway activity.

METHODS

Herein, we evaluate disproportionate reporting expressed as reporting odds ratios (ROR) for esketamine and ketamine. The outcomes of interest include alcohol problem, alcoholism, alcohol abuse, substance dependence, SUD, substance abuse, drug dependence, drug use disorder and drug abuse as codified by the Medical Dictionary for Regulatory Activities (MedDRA) within the FAERS. The IC025 values were significant for ketamine in cases of alcohol abuse (0.28), substance dependence (1.88), substance use disorder (0.996), substance abuse (0.61), drug dependence (0.56), drug use disorder (1.17) and drug abuse (1.22). Additionally, oxycontin showed significant IC025 values for substance dependence (0.067), substance use disorder (0.094), substance abuse (0.035), and drug dependence (0.27).

RESULTS

We observed significant increases in the reporting odds ratios (RORs) for ketamine with respect to various outcomes: alcohol abuse (ROR 2.84, 95 % CI 1.53-5.28; p = 0.0010), substance dependence (ROR 18.72, 95 % CI 8.49-41.30; p ≤ 0.0001), SUD (ROR 11.40, 95 % CI 4.24-30.65; p ≤ 0.0001), substance abuse (ROR 2.29, 95 % CI 1.73-3.04; p ≤ 0.0001), drug dependence (ROR 1.99, 95 % CI 1.64-2.42; p ≤ 0.0001), drug use disorder (ROR 4.50, 2.94-6.88; p ≤ 0.0001) and drug abuse (ROR 3.72, 3.36-4.12; p ≤ 0.0001). For esketamine, we observed that the ROR was significantly reduced for substance abuse (ROR 0.37, 95 % CI 0.22-0.63; p = 0.0003), drug dependence (ROR 0.13, 95 % CI 0.076-0.23; p ≤ 0.0001) and drug abuse (ROR 0.048, 95 % CI 0.030-0.078; p ≤ 0.0001). To our knowledge, this is the first report of spontaneous adverse events related to these outcomes of interest in the FAERS.

CONCLUSION

Mixed RORs were observed across aspects of SUD and AUD for both ketamine and esketamine. Due to limitations in the FAERS, establishing causal links between new onset alcohol and substance misuse with either agent remains inconclusive. Possible beneficial effects on measures of SUD and AUD were observed. It is currently unclear, but possible, whether both agents have differential ameliorative effects across dimensions of SUD and AUD, which is a focus of ongoing research.

Ketamine ameliorates post-traumatic social avoidance by erasing the traumatic memory encoded in VTA-innervated BLA engram cells

Erasing traumatic memory during memory reconsolidation is a promising retrieval-extinction strategy for post-traumatic stress disorder (PTSD). Here, we developed an acute social defeat stress (SDS) mouse model with short-term and re-exposure-evoked long-term social avoidance. SDS-associated traumatic memories were identified to be stored in basolateral amygdala (BLA) engram cells. A single intraperitoneal administration of subanesthetic-dose ketamine within, but not beyond, the re-exposure time window significantly alleviates SDS-induced social avoidance, which reduces the activity and quantity of reactivated BLA engram cells. Furthermore, activation or inhibition of dopaminergic projections from the ventral tegmental area to the BLA effectively mimics or blocks the therapeutic effect of re-exposure with ketamine and is dopamine D2 receptor dependent. Single-cell RNA sequencing reveals that re-exposure with ketamine triggered significant changes in memory-related pathways in the BLA. Together, our research advances the understanding of how ketamine mitigates PTSD symptoms and offers promising avenues for developing more effective treatments for trauma-related disorders.

Molecular signatures of astrocytes and microglia maladaptive responses to acute stress are rescued by a single administration of ketamine in a rodent model of PTSD

Stress affects the brain and alters its neuroarchitecture and function; these changes can be severe and lead to psychiatric disorders. Recent evidence suggests that astrocytes and microglia play an essential role in the stress response by contributing to the maintenance of cerebral homeostasis. These cells respond rapidly to all stimuli that reach the brain, including stressors. Here, we used a recently validated rodent model of post-traumatic stress disorder in which rats can be categorized as resilient or vulnerable after acute inescapable footshock stress. We then investigated the functional, molecular, and morphological determinants of stress resilience and vulnerability in the prefrontal cortex, focusing on glial and neuronal cells. In addition, we examined the effects of a single subanesthetic dose of ketamine, a fast-acting antidepressant recently approved for the treatment of resistant depression and proposed for other stress-related psychiatric disorders. The present results suggest a prompt glial cell response and activation of the NF-κB pathway after acute stress, leading to an increase in specific cytokines such as IL-18 and TNF-α. This response persists in vulnerable individuals and is accompanied by a significant change in the levels of critical glial proteins such as S100B, CD11b, and CX43, brain trophic factors such as BDNF and FGF2, and proteins related to dendritic arborization and synaptic architecture such as MAP2 and PSD95. Administration of ketamine 24 h after the acute stress event rescued many of the changes observed in vulnerable rats, possibly contributing to support brain homeostasis. Overall, our results suggest that pivotal events, including reactive astrogliosis, changes in brain trophic factors, and neuronal damage are critical determinants of vulnerability to acute traumatic stress and confirm the therapeutic effect of acute ketamine against the development of stress-related psychiatric disorders.

Ketamine in neuropsychiatric disorders: an update

The discovery of ketamine as a rapid-acting antidepressant led to a new era in the development of neuropsychiatric therapeutics, one characterized by an antidepressant response that occurred within hours or days rather than weeks or months. Considerable clinical research supports the use of-or further research with-subanesthetic-dose ketamine and its (S)-enantiomer esketamine in multiple neuropsychiatric disorders including depression, bipolar disorder, anxiety spectrum disorders, substance use disorders, and eating disorders, as well as for the management of chronic pain. In addition, ketamine often effectively targets symptom domains associated with multiple disorders, such as anxiety, anhedonia, and suicidal ideation. This manuscript: 1) reviews the literature on the pharmacology and hypothesized mechanisms of subanesthetic-dose ketamine in clinical research; 2) describes similarities and differences in the mechanism of action and antidepressant efficacy between racemic ketamine, its (S) and (R) enantiomers, and its hydroxynorketamine (HNK) metabolite; 3) discusses the day-to-day use of ketamine in the clinical setting; 4) provides an overview of ketamine use in other psychiatric disorders and depression-related comorbidities (e.g., suicidal ideation); and 5) provides insights into the mechanisms of ketamine and therapeutic response gleaned from the study of other novel therapeutics and neuroimaging modalities.

Stress-related cellular pathophysiology as a crosstalk risk factor for neurocognitive and psychiatric disorders

In this narrative review, we examine biological processes linking psychological stress and cognition, with a focus on how psychological stress can activate multiple neurobiological mechanisms that drive cognitive decline and behavioral change. First, we describe the general neurobiology of the stress response to define neurocognitive stress reactivity. Second, we review aspects of epigenetic regulation, synaptic transmission, sex hormones, photoperiodic plasticity, and psychoneuroimmunological processes that can contribute to cognitive decline and neuropsychiatric conditions. Third, we explain mechanistic processes linking the stress response and neuropathology. Fourth, we discuss molecular nuances such as an interplay between kinases and proteins, as well as differential role of sex hormones, that can increase vulnerability to cognitive and emotional dysregulation following stress. Finally, we explicate several testable hypotheses for stress, neurocognitive, and neuropsychiatric research. Together, this work highlights how stress processes alter neurophysiology on multiple levels to increase individuals' risk for neurocognitive and psychiatric disorders, and points toward novel therapeutic targets for mitigating these effects. The resulting models can thus advance dementia and mental health research, and translational neuroscience, with an eye toward clinical application in cognitive and behavioral neurology, and psychiatry.

Dopamine-Dependent Ketamine Modulation of Glutamatergic Synaptic Plasticity in the Prelimbic Cortex of Adult Rats Exposed to Acute Stress

Traumatic stress is the main environmental risk factor for the development of psychiatric disorders. We have previously shown that acute footshock (FS) stress in male rats induces rapid and long-lasting functional and structural changes in the prefrontal cortex (PFC), which are partly reversed by acute subanesthetic ketamine. Here, we asked if acute FS may also induce any changes in glutamatergic synaptic plasticity in the PFC 24 h after stress exposure and whether ketamine administration 6 h after stress may have any effect. We found that the induction of long-term potentiation (LTP) in PFC slices of both control and FS animals is dependent on dopamine and that dopamine-dependent LTP is reduced by ketamine. We also found selective changes in ionotropic glutamate receptor subunit expression, phosphorylation, and localization at synaptic membranes induced by both acute stress and ketamine. Although more studies are needed to understand the effects of acute stress and ketamine on PFC glutamatergic plasticity, this first report suggests a restoring effect of acute ketamine, supporting the potential benefit of ketamine in limiting the impact of acute traumatic stress.

Repeated oral esketamine in patients with treatment resistant depression and comorbid posttraumatic stress disorder

Introduction

Ketamine and its S-enantiomer esketamine are novel pharmacotherapeutic options for treatment resistant depression (TRD). There is growing evidence on the efficacy for other psychiatric disorders, including posttraumatic stress disorder (PTSD). It is hypothesized that psychotherapy may further potentiate the effects of (es)ketamine in psychiatric disorders.

Methods

Repeated oral esketamine was prescribed once or twice weekly in five patients suffering from TRD and comorbid PTSD. We describe the clinical effects of esketamine and report data from psychometric instruments and patients' perspectives.

Results

Esketamine treatment duration ranged from six weeks to a year. In four patients, we observed improvement in depressive symptoms, increased resilience and more receptiveness to psychotherapy. One patient experienced symptom worsening in response to a threatening situation during esketamine treatment, highlighting the need for a safe setting.

Discussion

(Es)ketamine treatment within a psychotherapeutic framework appears promising in patients with treatment resistant symptoms of depression and PTSD. Controlled trials are warranted to validate these results and to elucidate the optimal treatment methods.

Evidence for the beneficial effect of ketamine in the treatment of patients with post-traumatic stress disorder: A systematic review and meta-analysis

Post-traumatic stress disorder (PTSD) is an anxiety disorder with manifestations somatic resulting from reliving the trauma. The therapy for the treatment of PTSD has limitations, between reduced efficacy and "PTSD pharmacotherapeutic crisis". Scientific evidence has shown that the use of ketamine has benefits for the treatment of depressive disorders and other symptoms present in PTSD compared to other conventional therapies. Therefore, this study aims to analyze the available evidence on the effect of ketamine in the treatment of post-traumatic stress. The systematic review and the meta-analysis were conducted following PRISMA guidelines and RevManager software, using randomized controlled trials and eligible studies of quality criteria for data extraction and analysis. The sample design evaluated included the last ten years, whose search resulted in 594 articles. After applying the exclusion criteria, 35 articles were selected, of which 14 articles were part of the sample, however, only six articles were selected the meta-analysis. The results showed that the ketamine is a promising drug in the management of PTSD with effect more evident performed after 24 h evaluated by MADRS scale. However, the main limitations of the present review demonstrate that more high-quality studies are needed to investigate the influence of therapy, safety, and efficacy.

The effect of ketamine on cognition, anxiety, and social functioning in adults with psychiatric disorders: A systematic review and meta-analysis

Background

It has been shown that ketamine can improve suicidality and depression. Evidence for other dimensions of psychopathology is lacking. We undertook a systematic review to investigate the effect of ketamine on cognition, anxiety, quality of life, and social functioning in adults with psychiatric disorders.

Methods

PubMed (Medline), Scopus, PsycINFO, and EMBASE were searched up to April 2022. Randomized controlled trials (RCTs) on ketamine [or its S (+) enantiomer] reporting data on cognition, anxiety, quality of life, social functioning in adults with psychiatric disorders were included. Standardized mean difference (SMD) was used for summarizing continuous outcomes.

Results

Twenty-two reports were included in the final selection, of which 20, corresponding to 1,298 participants, were included in the quantitative synthesis. Affective disorders were the predominant diagnostic category. Median follow-up time was 21 days. The evidence was rated moderate to very low. In most trials, ketamine was administered intravenously or as adjuvant to electro-convulsant therapy (ECT). Only 2 trials of intranasal esketamine were identified. The effect of ketamine on depression was confirmed (SMD: -0.61 [95% CI: -1.06; -0.16]). Furthermore, by pooling results of 6 RCTs, ketamine may be effective in reducing anxiety symptoms (SMD: -0.42 [95% CI: -0.84; 0.003]), particularly when administered not within ECT (5 trials; SMD: -0.58 [95% CI: -1.07; -0.09]). However, there was moderate heterogeneity of results. Patients treated with ketamine also had an improvement in social functioning (SMD: -0.31 [95% CI: -0.52; -0.10]), although the estimate was based only on 2 studies. No difference to comparators was found with respect to cognition and quality of life.

Conclusion

Alongside the antidepressant effect, ketamine may also improve anxiety and social functioning in adults with affective disorders.