Real-world experience of esketamine use to manage treatment-resistant depression: A multicentric study on safety and effectiveness (REAL-ESK study)

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.

Long-term remission following esketamine nasal spray sessions in a patient with severe and highly treatment-resistant depression: a single-case report

About 30% of patients with major depressive disorder have treatment-resistant depression (TRD). Recently, intranasal esketamine was approved as a treatment option after the failure of two antidepressant trials. We report a patient with multiresistant depression that was successfully and safely treated with esketamine nasal spray. This 31-year-old inpatient with severe, chronic, and multi-TRD received an acute course of intranasal esketamine (84 mg). Previously, 14 different antidepressants, alone or in potentiation, and several neurostimulation techniques had been unsuccessful. Over 20 bi-weekly sessions, she had no significant adverse effects and was stabilized into remission. During the maintenance phase and 1 year after, she continues to be stable. This case report provides an example of a patient with severe TRD that showed significant improvement after treatment with intranasal esketamine.

Overcoming treatment-resistant depression with machine-learning based tools: a study protocol combining EEG and clinical data to personalize glutamatergic and brain stimulation interventions (SelecTool Project)

Treatment-Resistant Depression (TRD) poses a substantial health and economic challenge, persisting as a major concern despite decades of extensive research into novel treatment modalities. The considerable heterogeneity in TRD's clinical manifestations and neurobiological bases has complicated efforts toward effective interventions. Recognizing the need for precise biomarkers to guide treatment choices in TRD, herein we introduce the SelecTool Project. This initiative focuses on developing (WorkPlane 1/WP1) and conducting preliminary validation (WorkPlane 2/WP2) of a computational tool (SelecTool) that integrates clinical data, neurophysiological (EEG) and peripheral (blood sample) biomarkers through a machine-learning framework designed to optimize TRD treatment protocols. The SelecTool project aims to enhance clinical decision-making by enabling the selection of personalized interventions. It leverages multi-modal data analysis to navigate treatment choices towards two validated therapeutic options for TRD: esketamine nasal spray (ESK-NS) and accelerated repetitive Transcranial Magnetic Stimulation (arTMS). In WP1, 100 subjects with TRD will be randomized to receive either ESK-NS or arTMS, with comprehensive evaluations encompassing neurophysiological (EEG), clinical (psychometric scales), and peripheral (blood samples) assessments both at baseline (T0) and one month post-treatment initiation (T1). WP2 will utilize the data collected in WP1 to train the SelecTool algorithm, followed by its application in a second, out-of-sample cohort of 20 TRD subjects, assigning treatments based on the tool's recommendations. Ultimately, this research seeks to revolutionize the treatment of TRD by employing advanced machine learning strategies and thorough data analysis, aimed at unraveling the complex neurobiological landscape of depression. This effort is expected to provide pivotal insights that will promote the development of more effective and individually tailored treatment strategies, thus addressing a significant void in current TRD management and potentially reducing its profound societal and economic burdens.

A replication study using the World Health Organization pharmacovigilance database (VigiBase®) to evaluate whether an association between ketamine and esketamine and alcohol and substance misuse exists

BACKGROUND AND OBJECTIVES

Ketamine and esketamine are increasingly prescribed in the treatment of resistant mood disorders and persons at risk of suicide. Ketamine is a drug of misuse with increasing non-therapeutic use in the general population. Herein, our aim was to determine whether ketamine and/or esketamine are disproportionately associated with reports of substance and/or alcohol misuse.

METHODS

Replicating a similar analysis recently conducted using the Food and Drug Administration Adverse Event Reporting System (FAERS) database, we identified cases of "alcohol problem, alcoholism, alcohol abuse, substance dependence, substance use disorder (SUD), substance abuse, drug dependence, drug use disorder and drug abuse" in association with ketamine and esketamine reported to the World Health Organization Pharmacovigilance Database (WHO VigiBase). We searched the database from inception to January 2024. The reporting odds ratio (ROR) of each of the aforementioned parameters was calculated; acetaminophen was used as the control. The numerator of the equation represents the number of cases (n) and the denominator represents the total cases of psychiatric disorders (N). Significance was obtained when the lower limit of the 95 % confidence (CI) > 1.0.

RESULTS

The RORs for ketamine was increased for most parameters (i.e., alcohol abuse (3.24), substance dependence (12.48), substance use disorder (170.44), substance abuse (2.94), drug dependence (2.88), drug use disorder (11.54) and drug abuse (2.85), respectively). With respect to esketamine, the RORs were observed to be different from ketamine insofar as we observed a reduction in the RORs for three parameters (i.e., substance abuse (0.41), drug dependence (0.083) and drug abuse (0.052), respectively). The IC025 values were significant for ketamine in cases of alcohol abuse (0.35), substance dependence (0.50), substance use disorder (2.77), substance abuse (0.83), drug dependence (0.97), drug use disorder (1.95) and drug abuse (0.94). Additionally, oxycontin showed significant IC025 values for substance use disorder (0.0014), substance abuse (0.042), and drug dependence (0.17).

CONCLUSION

Esketamine was not associated with an increased ROR for any parameter of alcohol and/or substance use disorder. Mixed results were observed with ketamine with some RORs increased and others decreased. Estimating RORs using a pharmacovigilance database does not establish causation in the case of elevated RORs and cannot be assumed to be a therapeutic effect when lower RORs were observed.

Dopaminergic dysfunction in the left putamen of patients with major depressive disorder

INTRODUCTION

Dopaminergic transmission impairment has been identified as one of the main neurobiological correlates of both depression and clinical symptoms commonly associated with its spectrum such as anhedonia and psychomotor retardation.

OBJECTIVES

We examined the relationship between dopaminergic deficit in the striatum, as measured by 123I-FP-CIT SPECT imaging, and specific psychopathological dimensions in patients with major depressive disorder.

METHODS

To our knowledge this is the first study with a sample of >120 subjects. After check for inclusion and exclusion criteria, 121 (67 females, 54 males) patients were chosen retrospectively from an extensive 1106 patients database of 123I-FP-CIT SPECT scans obtained at the Nuclear Medicine Unit of Fondazione Policlinico Universitario Agostino Gemelli IRCCS in Rome. These individuals had undergone striatal dopamine transporter (DAT) assessments based on the recommendation of their referring clinicians, who were either neurologists or psychiatrists. At the time of SPECT imaging, each participant underwent psychiatric and psychometric evaluations. We used the following psychometric scales: Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, Snaith Hamilton Pleasure Scale, and Depression Retardation Rating Scale.

RESULTS

We found a negative correlation between levels of depression (p = 0.007), anxiety (p = 0.035), anhedonia (p = 0.028) and psychomotor retardation (p = 0.014) and DAT availability in the left putamen. We further stratified the sample and found that DAT availability in the left putamen was lower in seriously depressed patients (p = 0.027) and in patients with significant psychomotor retardation (p = 0.048).

CONCLUSION

To our knowledge this is the first study to have such a high number of sample. Our study reveals a pivotal role of dopaminergic dysfunction in patients with major depressive disorder. Elevated levels of depression, anxiety, anhedonia, and psychomotor retardation appear to be associated with reduced DAT availability specifically in the left putamen.

Number needed to treat (NNT) for ketamine and esketamine in adults with treatment-resistant depression: A systematic review and meta-analysis

BACKGROUND

Ketamine has been established as efficacious in adults living with Treatment-resistant Depression (TRD). Toward providing a quantifiable estimate of the clinical meaningfulness of the therapeutic benefit of ketamine, herein, we conduct a systematic review that aims to report the Number Needed to Treat (NNT) and the Number Needed to Harm (NNH).

METHODS

This systematic review searched Embase, Medline/Pubmed, PsycINFO and ClinicalTrials.gov from inception up to October 15th 2023, for placebo-controlled, Randomized Controlled Trials (RCTs) assessing racemic ketamine or esketamine therapy for unipolar TRD. We calculated NNT and NNH for ketamine treatments over various time points.

RESULTS

A total of 21 studies with 2042 participants were included. Racemic ketamine treatments had pooled NNTs for response of 7 at 4 h, 3 from one day to one week and 9 for studies at four weeks. Esketamine treatment was found to have a similar efficacy with an NNT of 2 at one day and 11 at four weeks. NNH values indicated low risk for ketamine treatments.

LIMITATIONS

Limitations in the data used include the possibility of functional unblinding and selective reporting bias. Moreover, the meta-analysis may have been limited in its precision by including low threshold definitions of treatment resistance (≥ 1 failed antidepressant) and low-dose ketamine treatments.

CONCLUSION

Herein, we determined that the NNT for ketamine treatment in adults living with TRD across different intervals of observation was <10. We conclude that the NNTs observed herein are highly clinically meaningful in this difficult to treat disorder.

Single arketamine in treatment resistant depression: Presentation of 3 cases with regard to sick-leave duration

BACKGROUND

Ketamine is the prototypal rapid-acting antidepressant (RAAD) for TRD with approved indication for esketamine-nasal spray (ESK-NS). Distinctly, arketamine (R-KET) demonstrates enhanced antidepressant effects and neuroplasticity changes compared to esketamine, with fewer dissociative side effects and abuse potential. This study focuses on R-ketamine's therapeutic implications, safety, and tolerability in TRD treatment.

METHODS

We report on a year-long follow-up of three TRD patients post-single IV R-KET administration. The study, conducted under the clinical trial PCN-101 (NCT05414422), observed these subjects for healthcare resource utilization and social support system impact. Participants, adults diagnosed with recurrent major depressive disorder without psychotic features, were observed in a year-long follow-up period for safety.

RESULTS

Case analyses revealed significant symptom reduction and improved social and vocational functioning, with reduced sick leaves and hospitalizations post-treatment. However, one case developed a substance use disorder, underscoring the need for vigilant monitoring. The study highlights R-KET's transformative potential in managing depression, indicating a shift in TRD treatment strategies towards early, aggressive interventions.

CONCLUSIONS

Despite promising findings, the study faces limitations due to its small sample size, lack of randomization, and potential observational design biases. The results, while aligning with existing ketamine research, require cautious interpretation and warrant further investigation with larger, more robust studies. This exploration of R-KET's role in home-based TRD treatment opens avenues for future research, particularly focusing on its long-term effectiveness and safety in diverse patient populations. This study is registered in clinicaltrials.gov: NCT06232291.

Efficacy of Esketamine among patients with treatment resistant depression in a 'real world' health-care setting in Israel

One in five people will likely suffer from major depressive disorder (MDD) during their life. Thirty percent of those with MDD will experience Treatment Resistant Depression (TRD), which is characterized by a failure to respond to two adequately administered trials of antidepressants. Esketamine is a rapidly acting intranasal antidepressant. Present-day Esketamine research has limited data in real-world populations. This study aimed to assess Esketamine treatment in a real-world community-based population. This naturalistic retrospective study included 94 individuals age 18 and above diagnosed with TRD, treated with Esketamine in an outpatient setting. The treatment was given in a single clinic, from January 2021 to January 2023, following approval of the Institutional Internal Review Board. The treatment included an acute phase (biweekly treatment, continuing 4-8 weeks), followed by a maintenance phase (once a week to once a month, for 6-12 months). Dosing ranged from 28 mg to 84 mg. Demographic and clinical data were retrospectively gathered. Depressive symptoms were assessed using the Quick Inventory of Depressive Symptomatology, at baseline and during each treatment phase. All patients completed the acute phase. About 60% completed the maintenance phase. Linear improvement of depressive symptoms was revealed in both phases. A sub-analysis of patients with comorbid personality disorder revealed a similar improvement pattern in the acute phase with milder improvement during the maintenance phase, compared to the other patients. This study supports the use of Esketamine for TRD, including patients with comorbid personality disorder and previous electroconvulsive therapy.

Treatment Patterns, Acute Healthcare Resource Use, and Costs of Patients with Treatment-Resistant Depression Completing Induction Phase of Esketamine in the United States

BACKGROUND

This study aimed to understand treatment patterns, acute healthcare use, and cost patterns among adults with treatment-resistant depression (TRD) who completed induction treatment with esketamine nasal spray in the United States (US). Per label, induction is defined as administration twice a week for 4 weeks, after which maintenance is started on a weekly basis for 4 weeks, and thereafter, patients are treated weekly or bimonthly.

METHODS

Adults with one or more esketamine claim (index date) on or after March 5, 2019 were selected from Optum's de-identified Clinformatics® Data Mart Database (January 2016-June 2022). Before the index date, patients had evidence of TRD and ≥ 12 months of continuous insurance eligibility (baseline period). Patients with eight or more esketamine treatment sessions were included in the main cohort. A subgroup included patients with one or more baseline mental health (MH)-related inpatient (IP) admission or emergency department (ED) visit (i.e., prior acute healthcare users). Treatment patterns were described during the follow-up period (index date until earliest of end of insurance eligibility or data); acute healthcare (i.e., IP and ED) resource use and costs (2021 US dollars) were reported during the baseline and follow-up periods.

RESULTS

Of the 322 patients in the main cohort, 111 comprised the subgroup of prior acute healthcare users. During the follow-up period, mean time from index date to eighth esketamine session was 73.2 days in the main cohort and 78.8 days in the subgroup (per label, 28 days). Further, 75.2% of the main cohort and 73.9% of the subgroup completed four or more esketamine maintenance sessions following induction. In the main cohort, mean all-cause acute healthcare costs per patient per month (PPPM) decreased from baseline ($837) to follow-up ($770). Similar reductions were observed for mean MH-related acute healthcare costs PPPM (baseline $648, follow-up $577). In the subgroup, mean all-cause acute healthcare costs PPPM also decreased (baseline $2323, follow-up $1423), driven by mean MH-related acute healthcare costs PPPM (baseline $1880, follow-up $1139). Mean all-cause acute healthcare use per ten patients per month remained largely stable from baseline to follow-up in the main cohort (IP days: baseline 2.24, follow-up 2.13; ED visits: baseline 1.33, follow-up 1.45) and decreased in the subgroup (IP days: baseline 6.38, follow-up 4.56; ED visits: baseline 2.58, follow-up 2.41). Trends in mean MH-related acute healthcare use were similar.

CONCLUSION

Patients generally required more time than label recommendation to complete esketamine induction treatment, and most went on to have 12 or more esketamine sessions. Completion of induction treatment correlated with reductions in mean all-cause and MH-related acute healthcare costs. Larger reductions were seen in the subgroup of prior acute healthcare users.

Facts and myths about use of esketamine for treatment-resistant depression: a narrative clinical review

Introduction and aims

Treatment-resistant depression (TRD) occurs when at least two different antidepressants, taken at the right dosage, for adequate period of time and with continuity, fail to give positive clinical effects. Esketamine, the S-enantiomer of ketamine, was recently approved for TRD treatment from U.S. Food and Drug Administration and European Medicine Agency. Despite proved clinical efficacy, many misconceptions by clinicians and patients accompany this medication. We aimed to review the most common "false myths" regarding TRD and esketemine, counterarguing with evidence-based facts.

Methods

The keywords "esketamine", "treatment resistance depression", "depression", "myth", "mythology", "pharmacological treatment", and "misunderstanding" were entered in the main databases and combined through Boolean operators.

Results

Misconceptions regarding the TRD prevalence, clinical features and predictors have been found. With respect of esketamine, criteria to start treatment, dissociative symptoms, potential addiction and aspects of administration and monitoring, were found to be affected by false beliefs by clinicians and patients.

Discussion and conclusion

TRD represents a challenging condition, requiring precise diagnosis in order to achieve patient's full recovery. Esketamine has been proved as an effective medication to treat TRD, although it requires precautions. Evidence can inform clinical practice, in order to offer this innovative treatment to all patients with TRD.

Depression with comorbid borderline personality disorder - could ketamine be a treatment catalyst?

Borderline personality disorder (BPD) is diagnosed in 10-30% of patients with major depressive disorder (MDD), and the frequency of MDD among individuals with BPD reaches over 80%. The comorbidity of MDD and BPD is associated with more severe depressive symptoms and functional impairment, higher risk of treatment resistance and increased suicidality. The effectiveness of ketamine usage in treatment resistant depression (TRD) has been demonstrated in numerous studies. In most of these studies, individuals with BPD were not excluded, thus given the high co-occurrence of these disorders, it is possible that the beneficial effects of ketamine also extend to the subpopulation with comorbid TRD and BPD. However, no protocols were developed that would account for comorbidity. Moreover, psychotherapeutic interventions, which may be crucial for achieving a lasting therapeutic effect in TRD and BPD comorbidity, were not included. In the article, we discuss the results of a small number of existing studies and case reports on the use of ketamine in depressive disorders with comorbid BPD. We elucidate how, at the molecular and brain network levels, ketamine can impact the neurobiology and symptoms of BPD. Furthermore, we explore whether ketamine-induced neuroplasticity, augmented by psychotherapy, could be of use in alleviating core BPD-related symptoms such as emotional dysregulation, self-identity disturbances and self-harming behaviors. We also discuss the potential of ketamine-assisted psychotherapy (KAP) in BPD treatment. As there is no standard approach to the application of ketamine or KAP in individuals with comorbid TRD and BPD, we consider further research in the field as imperative. The priorities should include development of dedicated protocols, distinguishing subpopulations that may benefit most from such treatment and investigating factors that may influence its effectiveness and safety.

How different definition criteria may predict clinical outcome in treatment resistant depression: Results from a prospective real-world study

Management of treatment-resistant depression (TRD) remains a major public health challenge, also due to the lack of a consensus around TRD definition. We investigated the impact of different definitions of TRD on identifying patients with distinct features in terms of baseline characteristics, treatment strategies, and clinical outcome. We conducted a prospective naturalistic study on 538 depressed inpatients. Patients were screened for treatment resistance by two TRD definitions: looser criteria (lTRD) and stricter criteria (sTRD). We compared baseline characteristics, treatment and clinical outcome between the TRD groups and their non-TRD counterparts. 52.97 % of patients were identified as lTRD, only 28.81 % met the criteria for sTRD. sTRD patients showed lower rates of remission and slower symptom reduction compared to non-TRD patients and received more challenging treatments. Surprisingly, patients identified as sTRD also exhibited lower rates of psychiatric comorbidities, including personality disorders, substance abuse, or alcohol misuse. Stricter TRD criteria identify patients with worse clinical outcomes. Looser criteria may lead to overdiagnosis and over treatment. Clinical features known to be possible risk factors for TRD, as psychiatric comorbidities, showed to be more suggestive of a "difficult to manage" depression rather than a proper TRD.

Risk factors for suicidal attempts in a sample of outpatients with treatment-resistant depression: an observational study

Introduction

Treatment-resistant depression (TRD) is commonly defined as the failure of at least two trials with antidepressant drugs, given at the right dose and for an appropriate duration. TRD is associated with increased mortality, compared to patients with a simple major depressive episode. This increased rate was mainly attributed to death from external causes, including suicide and accidents. The aim of our study is to identify socio-demographic and psychopathological variables associated with suicidal attempts in a sample of outpatients with TRD.

Material and methods

We performed a monocentric observational study with a retrospective design including a sample of 63 subjects with TRD referred to an Italian outpatient mental health centre. We collected socio-demographic and psychopathological data from interviews and clinical records.

Results

77.8% of the sample (N=49) were females, the mean age was 49.2 (15.9). 33.3% (N=21) of patients had attempted suicide. 54% (N=34) of patients had a psychiatric comorbidity. Among the collected variables, substance use (p=0.031), psychiatric comorbidities (p=0.049) and high scores of HAM-D (p=0.011) were associated with the occurrence of suicide attempts. In the regression model, substance use (OR 6.779), psychiatric comorbidities (OR 3.788) and HAM-D scores (OR 1.057) were predictive of suicide attempts. When controlling for gender, only substance use (OR 6.114) and HAM-D scores (OR 1.057) maintained association with suicide attempts.

Conclusion

The integrated treatment of comorbidities and substance abuse, which involves different mental health services, is fundamental in achieving the recovery of these patients. Our study supports the importance of performing a careful clinical evaluation of patients with TRD in order to identify factors associated with increased risk of suicide attempts.

The rapid antidepressant effectiveness of repeated dose of intravenous ketamine and intranasal esketamine: A post-hoc analysis of pooled real-world data

INTRODUCTION

Intravenous ketamine (KET-IV) and intranasal esketamine (ESK-NS) are effective in the acute treatment of Treatment-Resistant Depression (TRD). Studies comparing KET-IV and ESK-NS concerning their action, safety, and tolerability are currently lacking.

MATERIALS AND METHODS

We combined patients' data from two unipolar TRD cohorts that received KET-IV (n = 171) at the Canadian Rapid Treatment Center of Excellence in Toronto, Canada, or ESK-NS (n = 140) at several TRD clinics in Italy. The Quick Inventory for Depression Symptomatology-Self-Report-16/QIDS-SR16 in the KET-IV group and Montgomery-Åsberg Depression Rating Scale/MADRS in the ESK-NS group measured depressive symptoms at baseline (T0) and after the acute treatment phase (T1) (i.e., four infusions of KET-IV and eight administrations of ESK-NS). As different scales were used, the primary outcome was to compare the improvement in depression severity in the two cohorts by measuring effect sizes, response and remission rates. Finally, we compare side effects and discontinuation rates.

RESULTS

At T1, KET-IV and ESK-NS significantly reduced depressive symptoms (respectively: QIDS-SR16 mean reduction = 5.65, p < 0.001; MADRS mean reduction = 11.41, p = 0.025). KET-IV showed larger effect sizes compared to ESK-NS (1.666 vs. 1.244). KET-IV had higher response rates (36 % vs. 25 %; p = 0.042) but not superior remission rates (13 % vs. 12 %; p = 0.845) than ESK-NS at T1. Despite more reported side effects, KET-IV did not cause more discontinuations for adverse events (4.6 % vs. 2.12 %; p = 0.228) than ESK-NS.

CONCLUSION

KET-IV showed a higher short-term antidepressant effect, whereas ESK-NS exhibited lower side effects. Both were generally well tolerated. Future head-to-head studies should consider the long-term efficacy of these treatments.

French Society for Biological Psychiatry and Neuropsychopharmacology (AFPBN) guidelines for the management of patients with partially responsive depression and treatment-resistant depression: Update 2024

INTRODUCTION

The purpose of this update is to add newly approved nomenclatures and treatments as well as treatments yet to be approved in major depressive disorder, thus expanding the discussions on the integration of resistance factors into the clinical approach.

METHODS

Unlike the first consensus guidelines based on the RAND/UCLA Appropriateness Method, the French Association for Biological Psychiatry and Neuropsychopharmacology (AFPBN) developed an update of these guidelines for the management of partially responsive depression (PRD) and treatment-resistant depression (TRD). The expert guidelines combine scientific evidence and expert clinicians' opinions to produce recommendations for PRD and TRD.

RESULTS

The recommendations addressed three areas judged as essential for updating the previous 2019 AFPBN guidelines for the management of patients with TRD: (1) the identification of risk factors associated with TRD, (2) the therapeutic management of patients with PRD and TRD, and (3) the indications, the modalities of use and the monitoring of recent glutamate receptor modulating agents (esketamine and ketamine).

CONCLUSION

These consensus-based guidelines make it possible to build bridges between the available empirical literature and clinical practice, with a highlight on the 'real world' of the clinical practice, supported by a pragmatic approach centred on the experience of specialised prescribers in TRD.

Use of ketamine for treatment resistant depression: updated review of literature and practical applications to a community ketamine program in Edmonton, Alberta, Canada

Background

Though intravenous (IV) ketamine and intranasal (IN) esketamine are noted to be efficacious for treatment-resistant depression (TRD), access to each of these treatments within healthcare systems is limited due to cost, availability, and/or monitoring requirements. IV ketamine has been offered at two public hospital sites in Edmonton, Canada since 2015. Since then, demand for maintenance ketamine treatments has grown. This has required creative solutions for safe, accessible, evidence-based patient care.

Objectives

Aims of this paper are twofold. First, we will provide a synthesis of current knowledge with regards to the clinical use of ketamine for TRD. Consideration will be given regarding; off-label racemic ketamine uses versus FDA-approved intranasal esketamine, populations treated, inclusion/exclusion criteria, dosing, assessing clinical response, concomitant medications, and tolerability/safety. Second, this paper will describe our experience as a community case study in applying evidence-based treatment. We will describe application of the literature review to our clinical programming, and in particular focus on cost-effective maintenance treatments, long-term safety concerns, routes of ketamine administration other than via intravenous, and cautious prescribing of ketamine outside of clinically monitored settings.

Methodology

We conducted a literature review of the on the use of ketamine for TRD up to June 30, 2023. Key findings are reviewed, and we describe their application to our ketamine program.

Conclusion

Evidence for the use of ketamine in resistant depression has grown in recent years, with evolving data to support and direct its clinical use. There is an increasing body of evidence to guide judicious use of ketamine in various clinical circumstances, for a population of patients with a high burden of suffering and morbidity. While large-scale, randomized controlled trials, comparative studies, and longer-term treatment outcomes is lacking, this community case study illustrates that currently available evidence can be applied to real-world clinical settings with complex patients. As cost is often a significant barrier to accessing initial and/or maintenance IV or esketamine treatments, public ketamine programs may incorporate SL or IN ketamine to support a sustainable and accessible treatment model. Three of such models are described.

The efficacy of zuranolone in postpartum depression and major depressive disorder: a review & number needed to treat (NNT) analysis

INTRODUCTION

Major depressive disorder (MDD) is a common and debilitating mental illness. Postpartum depression (PPD) impacts women globally and is one of the most common complications of childbirth that is underdiagnosed and undertreated, adversely impacting the mental health of women, children, and partners.Available antidepressant medications require weeks to months before showing effect. In this setting, zuranolone, an oral neuroactive steroid and a positive allosteric modulator of GABAA receptors, is an attractive alternative as a rapid-acting antidepressant treatment.

AREAS COVERED

This article reviews zuranolone (SAGE217), focusing on available clinical studies in individuals with PPD and MDD. This paper adds to the extant literature by presenting the efficacy data as Number Needed to Treat (NNT) to facilitate indirect comparisons with other antidepressants.

EXPERT OPINION

Zuranolone is a novel rapid-acting (i.e. two week course) oral antidepressant for the treatment of adults with PPD with ongoing clinical trials evaluating its efficacy in adults with MDD. Zuranolone is well tolerated with no significant safety concerns in any clinical trials completed to date. Zuranolone will be scheduled by the Drug Enforcement Agency (DEA).

A Meta-Analysis of the Antidepressant Responses in Pivotal Trials on Esketamine Nasal Spray and Atypical Antipsychotics

Purpose

This meta-analysis assessed whether atypical antipsychotics (AAPs) and esketamine nasal spray (ESK-NS), which are mechanistically distinct, differ in antidepressant outcomes.

Patients and Methods

Data were extracted from 12 trials of ESK-NS or AAPs in depressed patients (4276) with inadequate response or resistance to conventional antidepressants. Montgomery-Åsberg Depression Rating Scale (MADRS) score reductions from baseline and response rates (≥50% reduction) were analyzed.

Results

At endpoint, the estimated MADRS score reduction of pooled ESK-NS arms was greater than pooled AAP arms (+9.16 points, p < 0.0001). The reduction also was greater in the pooled control arms of the ESK-NS trials than the pooled control arms of the AAP trials (+7.57 points, p < 0.0001). The mean difference in the reductions between pooled ESK-NS and control arms was 1.87 points greater than that between pooled AAP and control arms, but this difference was not significant (95% CI: -4.49, 0.74, p = 0.16). Relative to their respective control arms, the mean difference in response rates was 25% for the pooled ESK-NS and 9% for the pooled AAP arms; the mean response rate was 16% greater in the pooled ESK-NS studies than the pooled AAP studies (p = 0.0004). Comparisons against specific AAPs showed mean differences in the MADRS score reductions at 1 week between the experimental and control arms that were numerically larger in the ESK-NS trials than in the aripiprazole trials (mean difference of 1.71 points, p = 0.06) and the brexpiprazole trials (mean difference of 2.05 points, p = 0.02).

Conclusion

The ESK-NS arms showed numerically larger MADRS score reductions at week-1 and endpoint, and a significantly larger response rate compared with AAP arms. Prospective studies involving direct comparisons are warranted to compare the relative efficacy between these treatment regimens.

Stanford neuromodulation therapy for treatment-resistant depression: a systematic review

Objective

This systematic review of randomized controlled studies (RCTs) and observational studies evaluated the efficacy and safety of stanford neuromodulation therapy (SNT) for patients with treatment-resistant depression (TRD).

Methods

A systematic search (up to 25 September, 2023) of RCTs and single-arm prospective studies was conducted.

Results

One RCT (n = 29) and three single-arm prospective studies (n = 34) met the study entry criteria. In the RCT, compared to sham, active SNT was significantly associated with higher rates of antidepressant response (71.4% versus 13.3%) and remission (57.1% versus 0%). Two out of the three single-arm prospective studies reported the percentage of antidepressant response after completing SNT, ranging from 83.3% (5/6) to 90.5% (19/21). In the three single-arm prospective studies, the antidepressant remission rates ranged from 66.7% (4/6) to 90.5% (19/21). No severe adverse events occurred in all the four studies.

Conclusion

This systematic review found SNT significantly improved depressive symptoms in patients with TRD within 5 days, without severe adverse events.

The Efficacy and Safety of Intranasal Formulations of Ketamine and Esketamine for the Treatment of Major Depressive Disorder: A Systematic Review

Ketamine and its enantiomers represent an innovative glutamatergic agent as a treatment for individuals with treatment-resistant depression (TRD) and major depressive disorder (MDD) with suicidal ideation and behavior. Intranasal (IN) formulations could allow for quick onset of action on depressive symptoms as well as a reduction in side effects by bypassing the blood-brain barrier compared with administration via the intravenous route. The aim of this review was to provide an up-to-date analysis of the data on the efficacy and safety of IN ketamine and IN esketamine for the treatment of MDD. A systematic review following PRISMA guidelines was conducted. Databases (PubMed, Embase, MEDLINE, PsycINFO, and Google Scholar) were searched to capture articles about IN ketamine or IN esketamine for MDD. This systematic review highlighted the interest in IN routes of ketamine and esketamine for MDD patients with TRD or active suicidal ideation. They provide a rapid onset of antidepressant action within the first hours after administration. Nevertheless, the evidence of efficacy is stronger for IN esketamine than for IN ketamine in MDD patients. The safety profile appears to be acceptable for IN esketamine but requires further studies, and a more accurate IN delivery device is required for ketamine.

Investigating the Effectiveness and Tolerability of Intranasal Esketamine Among Older Adults With Treatment-Resistant Depression (TRD): A Post-hoc Analysis from the REAL-ESK Study Group

INTRODUCTION

Treatment-resistant depression (TRD) is a serious and debilitating psychiatric disorder that frequently affects older patients. Esketamine nasal spray (ESK-NS) has recently been approved as a treatment for TRD, with multiple studies establishing its efficacy and tolerability. However, the real-world effectiveness, tolerability, and safety of this treatment in older adults is still unclear.

OBJECTIVES

To evaluate the efficacy and tolerability of ESK-NS in older subjects with TRD.

METHODS

This is a post-hoc analysis of the REAL-ESK study, a multicenter, retrospective, observational study. Participants here selected were 65 years or older at baseline. The Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Rating Scale (HAM-A) were used to assess depressive and anxiety symptoms, respectively. Data were collected at three-time points: baseline, 1 month after the start of treatment (T1), and 3 months after treatment (T2).

RESULTS

The sample included older adults with TRD (n = 30). MADRS and HAM-A values decreased significantly at T1 (T0 versus T1: pholm <0.001, Cohen's d = 0.840) and T2 follow-ups (T0 versus T2: pholm <0.001, Cohen's d = 1.419). At T2, 53.3% of subjects were responders (MADRS score reduced ≥50%), while 33.33% were in remission (MADRS<10). ESK-NS-related adverse effects were in order of frequency dizziness (50%), followed by dissociation (33.3%), sedation (30%), and hypertension (13.33%). Six out of 30 participants (20%) discontinued treatment.

CONCLUSIONS

Our findings provide preliminary evidence of ESK-NS effectiveness in older adults with TRD, a highly debilitating depressive presentation. Furthermore, we observe high levels of treatment-emergent adverse events, which, in the majority of instances, did not require treatment suspension.

Nationwide consensus on the clinical management of treatment-resistant depression in Italy: a Delphi panel

BACKGROUND

Treatment-resistant depression (TRD) is defined by the European Medicines Agency as a lack of clinically meaningful improvement after treatment, with at least two different antidepressants. Individual, familiar, and socio-economic burden of TRD is huge. Given the lack of clear guidelines, the large variability of TRD approaches across different countries and the availability of new medications to meet the need of effective and rapid acting therapeutic strategies, it is important to understand the consensus regarding the clinical characteristics and treatment pathways of patients with TRD in Italian routine clinical practice, particularly in view of the recent availability of esketamine nasal spray.

METHODS

A Delphi questionnaire with 17 statements (with a 7 points Likert scale for agreement) was administered via a customized web-based platform to Italian psychiatrists with at least 5 years of experience and specific expertise in the field of depression. In the second-round physicians were asked to answer the same statements considering the interquartile range of each question as an index of their colleagues' responses. Stata 16.1 software was used for the analyses.

RESULTS

Sixty panellists, representative of the Italian territory, answered the questionnaire at the first round. For 8/17 statements more than 75% of panellists reached agreement and a high consensus as they assigned similar scores; for 4 statements the panellists assigned similar scores but in the middle of the Likert scale showing a moderate agreement with the statement, while for 5 statements there was indecision in the agreement and low consensus with the statement.

CONCLUSIONS

This Delphi Panel showed that there is a wide heterogeneity in Italy in the management of TRD patients, and a compelling need of standardised strategies and treatments specifically approved for TRD. A high level of consensus and agreement was obtained about the importance of adding lithium and/or antipsychotics as augmentation therapies and in the meantime about the need for long-term maintenance therapy. A high level of consensus and agreement was equally reached for the identification of esketamine nasal spray as the best option for TRD patients and for the possibility to administrate without difficulties esketamine in a community outpatient setting, highlighting the benefit of an appropriate educational support for patients.

Effects of transcranial magnetic stimulation on cocaine addiction: A systematic review of randomized controlled trials

OBJECTIVE

While pharmacological strategies appear to be ineffective in treating long-term addiction, repetitive transcranial magnetic stimulation (rTMS) is emerging as a promising new tool for the attenuation of craving among multiple substance dependent populations.

METHOD

A systematic review of randomized controlled trials (RCTs) was conducted on the efficacy and tolerability of rTMS in treating cocaine use disorder (CUD). Relevant papers published in English through November 30th 2022 were identified, searching the electronic databases MEDLINE, Embase, PsycINFO and the Cochrane Library.

RESULTS

Eight studies matched inclusion criteria. The best findings were reported by the RCTs conducted at high-frequency (≥5 Hz) multiple sessions of rTMS delivered over the left dorsolateral prefrontal cortex (DLPFC): a significant decrease in self-reported cue-induced cocaine craving and lower cocaine craving scores and a considerable amelioration in the tendency to act rashly under extreme negative emotions (impulsivity) were found in the active group compared to controls.

CONCLUSION

Although still scant and heterogeneous, the strongest evidence so far on the use of rTMS on individuals with CUD support the high frequency stimulation over the left DLPFC as a well tolerated treatment of cocaine craving and impulsivity.

Indirect adjusted comparison of 6-month clinical outcomes between esketamine nasal spray and other real-world polypharmacy treatment strategies for treatment resistant depression: results from the ICEBERG study

Background

The efficacy of esketamine nasal spray (NS) as a rapid-acting agent for treatment resistant depression (TRD) was demonstrated in comparisons with placebo, when both were given in addition to a newly initiated selective serotonin reuptake inhibitor (SSRI)/serotonin norepinephrine reuptake inhibitor (SNRI). How esketamine NS compares with commonly used real-world (RW) polypharmacy treatment strategies is not known.

Method

ICEBERG was an adjusted indirect treatment comparison that analysed data from SUSTAIN-2 (NCT02497287; clinicaltrials.gov), a long-term, open-label study of esketamine NS plus SSRI/SNRI, and the European Observational TRD Cohort (EOTC; NCT03373253; clinicaltrials.gov), an observational study of routine clinical practice. Data were compared between patients receiving esketamine NS (SUSTAIN-2) and those from the EOTC treated with polypharmacy treatment strategies, either combination or augmentation. Analyses were adjusted for potential confounders, using rescaled average treatment effect among treated estimates. Threshold analyses were conducted to assess potential impact of unmeasured confounders on the robustness of analyses where esketamine NS was found to be significantly superior. Sensitivity analyses were used to understand the impact of analysis method selection and data handling.

Results

Esketamine NS treatment resulted in a higher probability of 6-month response (49.7% [95% confidence interval (CI) 45.6-53.9]) and remission (33.6% [95% CI 29.7-37.6]) versus RW polypharmacy (26.8% [95% CI 21.0-32.5] and 19.4%, [95% CI 14.2-24.6], respectively). Relative risk calculations showed esketamine NS was 1.859 (95% CI 1.474-2.345; p < 0.0001) times as likely to result in response and 1.735 (1.297-2.322; p = 0.0002) times as likely to result in remission versus RW polypharmacy at 6 months. Threshold and extensive sensitivity analyses supported that analyses of esketamine NS superiority were robust.

Conclusion

ICEBERG supports esketamine NS being superior to current RW individualized polypharmacy strategies, including augmentation, with benefits extending beyond acute use, to improved chance of 6-month response and remission. While unobserved confounding factors may certainly impact results of an indirect comparison, threshold analysis supported a low likelihood of this affecting the conclusions.To view an animated summary of this publication, please click on the Supplementary video.

The Patient's Perspective on the Effects of Intranasal Esketamine in Treatment-Resistant Depression

The effectiveness of the esketamine nasal spray (ESK-NS) for treatment-resistant depression (TRD) has been confirmed by real-world studies. Available evidence derived from clinician-rated assessments might differ from patients' perceptions about the helpfulness of treatments. We aimed to verify the effect of ESK-NS from patients' view in 25 TRD patients (56% males, 55.1 ± 10.9 years) treated with ESK-NS (mean dose: 78.4 ± 11.43 mg) for three months and evaluated at different time-points through clinician-rated and self-administered scales, assessing changes in depression, anhedonia, sleep, cognition, suicidality, and anxiety. We observed an overall early improvement that lasted over time (endpoint total score reduction in Montgomery-Åsberg Depression Rating Scale, p < 0.001, Beck Depression Inventory, p = 0.003). Patients reported a significant self-rated decrease in anhedonia at two months (Snaith-Hamilton Pleasure Scale, p = 0.04) and in suicide ideation at endpoint (BDI subitem 9, p = 0.039) vs. earlier improvements detected by clinicians (one-month reduction in MADRS subitem 8, p = 0.005, and subitem 10, p = 0.007). These findings confirm the effectiveness of a three-month treatment with ESK-NS in TRD patients, highlighting an overall overlapping response from patients' and clinicians' perspectives, although with some differential effects on specific symptoms at given time-points. Including patients' viewpoints in routine assessments could inform clinical practice, ensuring a better characterization of clinical phenotypes to deliver personalized interventions.

Esketamine in treatment-resistant depression patients comorbid with substance-use disorder: A viewpoint on its safety and effectiveness in a subsample of patients from the REAL-ESK study

Esketamine, the S-enantiomer of ketamine, has recently emerged as a therapy for treatment-resistant depression (TRD), showing both rapid antidepressant action and good efficacy and high safety. It is also indicated for the acute short-term treatment of psychiatric emergency due to major depressive disorder (MDD) and for depressive symptoms in adults with MDD with acute suicidal thoughts/behavior. We here provide preliminary insights on esketamine nasal spray (ESK-NS) effectiveness and safety among patients with a substance use disorder (SUD) within the sample of patients with TRD collected for the observational, retrospective, multicentre REAL-ESK study. Twenty-six subjects were retrospectively selected according to the presence of a SUD in comorbidity. Subjects enrolled completed the three different follow-up phases (T0/baseline, T1/after one month, and T2/after three months) and there were no dropouts. A decrease in Montgomery-Asberg depression rating scale (MADRS) scores was recorded, thus highlighting the antidepressant efficacy of ESK-NS (MADRS decreased from T0 to T1, t = 6.533, df=23, p<0.001, and from T1 to T2, t = 2.029, df=20, p = 0.056). Considering tolerability and safety issues, one or more side effects were reported by 19/26 subjects (73%) after treatment administration. All reported side effects were time-dependent and did not cause significant sequelae; among them, dissociative symptoms (38%) and sedation (26%) were the most frequently reported. Finally, no cases of abuse or misuse of ESK-NS were reported. Despite study limitations related to the inherent nature of the study, a limited number of patients, and a short follow-up period, ESK-NS showed to be effective and safe in patients diagnosed with TRD comorbid with a SUD.

Predicting outcome with Intranasal Esketamine treatment: A machine-learning, three-month study in Treatment-Resistant Depression (ESK-LEARNING)

Treatment-resistant depression (TRD) represents a severe clinical condition with high social and economic costs. Esketamine Nasal Spray (ESK-NS) has recently been approved for TRD by EMA and FDA, but data about predictors of response are still lacking. Thus, a tool that can predict the individual patients' probability of response to ESK-NS is needed. This study investigates sociodemographic and clinical features predicting responses to ESK-NS in TRD patients using machine learning techniques. In a retrospective, multicentric, real-world study involving 149 TRD subjects, psychometric data (Montgomery-Asberg-Depression-Rating-Scale/MADRS, Brief-Psychiatric-Rating-Scale/BPRS, Hamilton-Anxiety-Rating-Scale/HAM-A, Hamilton-Depression-Rating-Scale/HAMD-17) were collected at baseline and at one month/T1 and three months/T2 post-treatment initiation. We trained three different random forest classifiers, able to predict responses to ESK-NS with accuracies of 68.53% at T1 and 66.26% at T2 and remission at T2 with 68.60% of accuracy. Features like severe anhedonia, anxious distress, mixed symptoms as well as bipolarity were found to positively predict response and remission. At the same time, benzodiazepine usage and depression severity were linked to delayed responses. Despite some limitations (i.e., retrospective study, lack of biomarkers, lack of a correct interrater-reliability across the different centers), these findings suggest the potential of machine learning in personalized intervention for TRD.

Therapeutic Protocols Using Ketamine and Esketamine for Depressive Disorders: A Systematic Review

Depression is one of the most prevalent mental health disorders globally, causing severe emotional suffering, reducing life expectancy and increasing the risk of suicide. Recently, the use of dissociative psychedelic substances such as ketamine and esketamine for depressive disorders has expanded treatment options. We sought to analyze, through a systematic review, the existing protocols for the treatment of depression with ketamine and esketamine. The search adopted PRISMA criteria and was performed using PubMed and Web of Science databases. Procedures in each study were compared, focusing on the sample recruited, therapeutic approaches, including the clinical team and professionals engaged in treatment, medical procedures, description of the setting (including music) and factors such as specific medication (ketamine or esketamine), route of administration and dosage employed. Results indicated the predominance of a medical approach, with a limited number of studies on ketamine assisted psychotherapy (KAP) and other modalities of psychedelic assisted therapy. Additionally, there is limited information on psychosocial elements such as preparation, psychological support during session and integration of experience. Altogether these findings suggest that treatment of depression with ketamine or esketamine diverges in relation to the practices employed with psychedelic substances. This is discussed considering future research directions in the field.

Efficacy and Safety of Esketamine Nasal Spray in Patients with Treatment-Resistant Depression Who Completed a Second Induction Period: Analysis of the Ongoing SUSTAIN-3 Study

BACKGROUND

Treatment-resistant depression (TRD) is a chronic illness requiring long-term treatment. Esketamine nasal spray (ESK) has been studied in several long-term trials of patients with TRD, including SUSTAIN-1 (NCT02493868) and SUSTAIN-3 (NCT02782104). This subgroup analysis of SUSTAIN-3 evaluated patients with TRD who received a second induction (IND) and maintenance treatment with ESK plus oral antidepressant (AD) after a relapse in SUSTAIN-1.

METHODS

Patients aged 18-64 years who achieved stable remission or response with ESK and subsequently relapsed after randomization to continue ESK or switch to placebo nasal spray (PBO) in SUSTAIN-1 and entered the IND phase of SUSTAIN-3 were included in this interim analysis. Response (≥50% improvement in total score from baseline for Montgomery-Åsberg Depression Rating Scale [MADRS] and Patient Health Questionnaire 9-item [PHQ-9]), remission (MADRS score ≤12; PHQ-9 total score <5), changes in depression rating scores (measured as mean change from baseline), and safety were evaluated (incidence of treatment-emergent and serious adverse events [AE]).

RESULTS

Of the 96 eligible patients who entered IND in SUSTAIN-3, 32 (33.3%) were taking ESK+AD at the time of relapse in SUSTAIN-1 and 64 (66.7%) were taking AD+PBO. Substantial improvements in depressive symptoms were observed over the second IND phase in both groups and were maintained over the optimization/maintenance (OP/M) phase. MADRS response rates following a second IND were 71.9% and 73.4% for previously relapsed (PR) ESK+AD and PR-AD+PBO, respectively; remission rates were 62.5% and 60.9%, respectively. During the IND and OP/M phases, 58.3% and 83.3% of patients experienced a treatment-emergent AE, respectively. No patients discontinued due to an AE during the second IND.

CONCLUSIONS

Patients with TRD benefitted from receiving a second IND and maintenance treatment with ESK and no new safety signals were identified.

The antidepressant actions of ketamine and its enantiomers

Ketamine, an N-methyl-d-aspartate receptor (NMDAR) antagonist first developed as an anesthetic, has shown significant promise as a medication with rapid antidepressant properties in treatment-resistant depression. However, concerns such as adverse side effects and potential misuse liability have limited its widespread use. Racemic ketamine has two enantiomers-(S)- and (R)-ketamine-that appear to have disparate underlying mechanisms. This brief review summarizes some of the most recent preclinical and clinical research regarding the convergent and divergent prophylactic, immediate, and sustained antidepressant effects of (S)- and (R)-ketamine while addressing potential differences in their side effect and misuse liability profiles. Preclinical research suggests divergent mechanisms underlying (S)- and (R)-ketamine, with (S)-ketamine more directly affecting mechanistic target of rapamycin complex 1 (mTORC1) signaling and (R)-ketamine more directly affecting extracellular signal-related kinase (ERK) signaling. Clinical research suggests that (R)-ketamine has a milder side effect profile than (S)-ketamine and decreases depression rating scale scores, but recent randomized, controlled trials found that it had no significant antidepressant efficacy compared to placebo, suggesting that caution is warranted in interpreting its therapeutic potential. Future preclinical and clinical research is needed to maximize the efficacy of each enantiomer, either by optimizing dose, route of administration, or administration paradigm.

Treating bipolar depression with esketamine: Safety and effectiveness data from a naturalistic multicentric study on esketamine in bipolar versus unipolar treatment-resistant depression

BACKGROUND

Bipolar depression accounts for most of the disease duration in type I and type II bipolar disorder (BD), with few treatment options, often poorly tolerated. Many individuals do not respond to first-line therapeutic options, resulting in treatment-resistant bipolar depression (B-TRD). Esketamine, the S-enantiomer of ketamine, has recently been approved for treatment-resistant depression (TRD), but no data are available on its use in B-TRD.

OBJECTIVES

To compare the efficacy of esketamine in two samples of unipolar and bipolar TRD, providing preliminary indications of its effectiveness in B-TRD. Secondary outcomes included the evaluation of the safety and tolerability of esketamine in B-TRD, focusing on the average risk of an affective switch.

METHODS

Thirty-five B-TRD subjects treated with esketamine nasal spray were enrolled and compared with 35 TRD patients. Anamnestic data and psychometric assessments (Montgomery-Asberg Depression Rating Scale/MADRS, Hamilton-depression scale/HAM-D, Hamilton-anxiety scale/HAM-A) were collected at baseline (T0), at one month (T1), and three months (T2) follow up.

RESULTS

A significant reduction in depressive symptoms was found at T1 and T2 compared to T0, with no significant differences in response or remission rates between subjects with B-TRD and TRD. Esketamine showed a greater anxiolytic action in subjects with B-TRD than in those with TRD. Improvement in depressive symptoms was not associated with treatment-emergent affective switch.

CONCLUSIONS

Our results supported the effectiveness and tolerability of esketamine in a real-world population of subjects with B-TRD. The low risk of manic switch in B-TRD patients confirmed the safety of this treatment.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

Rethinking ketamine and esketamine action: Are they antidepressants with mood-stabilizing properties?

Ketamine and esketamine, the S-enantiomer of the racemic mixture, have recently generated considerable interest as potential therapeutic agents for Treatment-Resistant Depression (TRD), a complex disorder that includes various psychopathological dimensions and distinct clinical profiles (e.g., comorbid personality disorder, bipolar spectrum, dysthymic disorder). This perspective article provides a comprehensive overview of the action of ketamine/esketamine from a dimensional point of view, taking into account the high prevalence of bipolarity in TRD and the evidence of the efficacy of these substances on mixed features, anxiety, dysphoric mood, and, generally, bipolar traits. Additionally, the article underscores the complexity of the pharmacodynamic mechanisms of action of ketamine/esketamine, which goes beyond the non-competitive antagonism of NMDA-R. The need for further research and evidence is highlighted, mainly to evaluate the efficacy of esketamine nasal spray in bipolar depression, the presence of bipolar elements as a predictor of response, and the potential role of these substances as mood stabilizers. The article implies that, in the future, ketamine/esketamine could be used with fewer limitations, not only as antidepressants for the most severe form of depression but also as valuable tools to stabilize subjects with mixed symptoms or bipolar spectrum.

Comparison on the clinical features in patients with or without treatment-resistant depression: A National Survey on Symptomatology of Depression report

Patients with treatment-resistant depression (TRD) have fewer treatment options and worse prognoses than those without TRD. Although the etiology or pathophysiology of TRD remains unclear, certain clinical variables have been found to be related to its severity and prognosis. Therefore, 1151 patients with recurrent depression were recruited from the National Survey on Symptomatology of Depression (NSSD) and their depressive symptoms were assessed by using the doctor-rating assessment questionnaire. Then, the differences between patients with or without TRD were compared by parametric or nonparametric tests and the risk factors for TRD were explored by logistic regression. The results showed there were differences in clinical variables between patients with and without TRD. Additionally, we found depression with more somatic symptoms had a higher risk for TRD. Further analysis by stepwise logistic regression showed that age, gender, religious belief, drinking habit, the total course of depression, the number of hospitalizations, characteristics of seasonal episode remission, depressed mood, hypersexuality, emotionally incoherent psychotic symptoms, psychomotor agitation, respiratory system symptoms and history of suicide attempts were strongly associated with TRD. So, it is crucial for clinicians to identify these clinical features and adjust treatments timely.

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.