Cardiac Safety of Esketamine Nasal Spray in Treatment-Resistant Depression: Results from the Clinical Development Program

Efficacy of ketamine versus esketamine in the treatment of perioperative depression: A review

Depression is a significant factor contributing to postoperative occurrences, and patients diagnosed with depression have a higher risk for postoperative complications. Studies on cardiovascular surgery extensively addresses this concern. Several studies report that people who undergo coronary artery bypass graft surgery have a 20% chance of developing postoperative depression. A retrospective analysis of medical records spanning 21 years, involving 817 patients, revealed that approximately 40% o individuals undergoing coronary artery bypass grafting (CABG) were at risk of perioperative depression. Patients endure prolonged suffering from illness because each attempt with standard antidepressants requires several weeks to be effective. In addition, multi-drug combination adjuvants or combination medication therapy may alleviate symptoms for some individuals, but they also increase the risk of side effects. Conventional antidepressants primarily modulate the monoamine system, whereas different therapies target the serotonin, norepinephrine, and dopamine systems. Esketamine is a fast-acting antidepressant with high efficacy. Esketamine is the S-enantiomer of ketamine, a derivative of phencyclidine developed in 1956. Esketamine exerts its effect by targeting the glutaminergic system the glutaminergic system. In this paper, we discuss the current depression treatment strategies with a focus on the pharmacology and mechanism of action of esketamine. In addition, studies reporting use of esketamine to treat perioperative depressive symptoms are reviwed, and the potential future applications of the drug are presented.

Apoptotic mechanism of development inhibition in zebrafish induced by esketamine

Esketamine, a widely used intravenous general anesthetic, is also employed for obstetric and pediatric anesthesia, and depression treatment. However, concerns regarding esketamine abuse have emerged. Moreover, the potential in vivo toxicity of esketamine on growth and development remains unclear. To address these concerns, we investigated the effects of esketamine exposure on developmental parameters, cell apoptosis, and gene expression in zebrafish. Esketamine exposure concentration-dependently decreased the heart rate and body length of zebrafish embryos/larvae while increasing the hatching rate and spontaneous movement frequency. Developmental retardation of zebrafish larvae, including shallow pigmentation, small eyes, and delayed yolk sac absorption, was also observed following esketamine treatment. Esketamine exposure altered the expression of apoptosis-related genes in zebrafish heads, primarily downregulating bax, caspase9, caspase3, caspase6, and caspase7. Intriguingly, BTSA1, a Bax agonist, reversed the anti-apoptotic and decelerated body growth effects of esketamine in zebrafish. Collectively, our findings suggest that esketamine may hinder embryonic development by inhibiting embryonic apoptosis via the Bax/Caspase9/Caspase3 pathway. To the best of our knowledge, this is the first study to report the lethal toxicity of esketamine in zebrafish. We have elucidated the developmental toxic effects of esketamine on zebrafish larvae and its potential apoptotic mechanisms. Further studies are warranted to evaluate the safety of esketamine in animals and humans.

Cardiovascular risk factors and metabolic syndrome in patients treated with long-acting injectables antipsychotics: a retrospective study

The present cross-sectional, retrospective study aimed to assess the prevalence of cardiovascular disease (CVD) risk factors and metabolic syndrome in a sample of psychiatric patients treated with long-acting injectable antipsychotics (LAIs). The clinical charts of 120 patients, mainly diagnosed with schizophrenia (30.0%), schizoaffective disorder (15.0%), and bipolar disorder (13.3%) on LAIs therapy - initiated in the period from 2013 to 2019 and lasting at least one year - were retrospectively reviewed and related socio-demographic, clinical and laboratory variables were collected. The 70.8% of patients were treated with first-generation LAIs, and the remaining 29.2% with second-generation LAIs. The overall sample showed low compliance in performing the required exams and evaluations related to CVD risk factors. The prevalence of metabolic syndrome was 30.8%, and, considering specific CVD risk factors, 55% of the total sample reported abdominal obesity, 43.3% arterial hypertension, 41.7% low HDL-cholesterol, 25.8% hypertriglyceridemia, and 20.8% fasting hyperglycemia. Lastly, 6.7% showed prolonged corrected QT (QTc) interval at the ECG. Patients treated with LAIs should be regularly monitored for metabolic changes and CVD risk factors. Metabolic changes rapidly develop after initiating an antipsychotic therapy and these often involve parameters, that can be easily recorded in an outpatient setting (e.g. abdominal obesity and hypertension).

Treatment patterns, healthcare utilization, and costs of patients with treatment-resistant depression initiated on esketamine intranasal spray and covered by US commercial health plans

AIMS

To describe real-world use of esketamine (ESK) intranasal spray and healthcare outcomes among patients with treatment-resistant depression (TRD) in the United States (US).

METHODS

Adults with TRD initiated on ESK (index date) between 5 March 2019 (US approval date for TRD) and 31 October 2020 were sampled from IBM MarketScan Research Databases. TRD was defined as claims for ≥2 unique antidepressants during the same major depressive episode. Subgroups of the TRD cohort with comorbid cardiometabolic conditions, pain, anxiety disorder, and substance use disorder (SUD) were identified. Patients had ≥6 months of continuous health plan eligibility pre- and post-index.

RESULTS

The TRD cohort comprised 269 patients; comorbidity subgroups included 123 (cardiometabolic), 144 (pain), 189 (anxiety disorder), and 58 (SUD) patients. Proportion of patients completing ≥8 ESK sessions (number of sessions in induction phase) was 61.3% in the TRD cohort and ranged from 60.2% (cardiometabolic subgroup) to 72.4% (SUD subgroup) in subgroups. Median frequency of induction sessions was every 5-8 days among the TRD cohort and subgroups. Mean mental health-related inpatient costs reduced from pre- to post-index periods in the TRD cohort (mean ± standard deviation [median] costs per-patient-per-6-months: $3,480 ± $13,328 [$0] pre-ESK initiation; $3,262 ± $16,666 [$0] post-ESK initiation; mean difference: -$218) and subgroups (largest decrease in cardiometabolic subgroup: $4,864 ± $14,271 [$0]; $2,792 ± $15,757 [$0]; -$2,072). Mean mental health-related emergency department (ED) costs decreased in the TRD cohort ($608 ± $2,525 [$0]; $269 ± $1,143 [$0]; -$339) and subgroups (largest decrease in the SUD subgroup: $1,403 ± $3,752 [$0]; $351 ± $868 [$0]; -$1,052).

LIMITATIONS

This is a descriptive analysis; sample size for some comorbidity subgroups is small.

CONCLUSIONS

The majority of patients completed ESK induction phase, and most dosing intervals were longer than the label recommendation. In this descriptive analysis, mental health-related inpatient and ED costs trended lower post-ESK initiation.

Impact of Repeated Doses of Subcutaneous Esketamine on Acute Dissociative Symptoms in Treatment-Resistant Depression

BACKGROUND

Esketamine has been approved by the US Food and Drug Administration (FDA) as an adjunctive treatment for use in conjunction with an oral antidepressant for patients with treatment-resistant depression (TRD), but dissociative symptoms are common adverse effects.

METHODS

A retrospective analysis of 394 subcutaneous esketamine injections given to 70 patients with TRD that were administered once a week during a six-week trial in conjunction with oral antidepressant therapy. Doses between 0.5 to 1.0 mg/kg were administered according to the patient's response. Dissociative symptoms were assessed using the Clinician-Administered Dissociative States Scale (CADSS) 30 and 60 min after every weekly treatment (day 1, 8, 15, 22, 29 and 36).

RESULTS

Seventy patients received a total of 394 subcutaneous esketamine injections over six weeks. Over time, the evolution of CADSS scores demonstrated a significant mean difference of CADSS at 60 min post-injection (p = 0.010) throughout the six infusions. The mean CADSS scores at 60 min on day 22, 29 and 36 were similar. There were no differences between mean CADSS scores 30 min after the injections, no clinical correlation between response and dissociative symptoms, no correlation between time and demographic and clinical characteristics and no interactions between time and combined medication.

CONCLUSIONS

Our results suggest that repeated subcutaneous esketamine doses are safe and well-tolerated regarding their acute dissociative and psychotomimetic symptoms. Symptoms usually peak at 30 min and decrease at 60 min post-injection, returning to their pretreatment levels at 120 min. Dissociative symptoms do not correlate with antidepressant response.

Esketamine-A quick-acting novel antidepressant without the disadvantages of ketamine

Esketamine, which is an S-enantiomer of ketamine, is better than conventional antidepressants and even better than R-ketamine. This article discusses the mechanism of action of Esketamine, how different it is from other antidepressants, its side effect profile, indications for use, various routes of administration and the review of existing literature on Esketamine.

Comprehensive care for people living with heart failure and chronic obstructive pulmonary disease—Integration of palliative care with disease-specific care: From guidelines to practice

Heart failure (HF) and chronic obstructive pulmonary disease (COPD) are the leading global epidemiological, clinical, social, and economic burden. Due to similar risk factors and overlapping pathophysiological pathways, the coexistence of these two diseases is common. People with severe COPD and advanced chronic HF (CHF) develop similar symptoms that aggravate if evoking mechanisms overlap. The coexistence of COPD and CHF limits the quality of life (QoL) and worsens symptom burden and mortality, more than if only one of them is present. Both conditions progress despite optimal, guidelines directed treatment, frequently exacerbate, and have a similar or worse prognosis in comparison with many malignant diseases. Palliative care (PC) is effective in QoL improvement of people with CHF and COPD and may be a valuable addition to standard treatment. The current guidelines for the management of HF and COPD emphasize the importance of early integration of PC parallel to disease-modifying therapies in people with advanced forms of both conditions. The number of patients with HF and COPD requiring PC is high and will grow in future decades necessitating further attention to research and knowledge translation in this field of practice. Care pathways for people living with concomitant HF and COPD have not been published so far. It can be hypothesized that overlapping of symptoms and similarity in disease trajectories allow to draw a model of care which will address symptoms and problems caused by either condition.

Long-term safety of ketamine and esketamine in treatment of depression

INTRODUCTION

Ketamine is an NMDA receptor antagonist that can produce rapid-acting antidepressant effects. Esketamine (Spravato), the S-enantiomer of racemic ketamine, was approved by the FDA for treatment-resistant depression in 2019. Here we review what is known about the long-term safety of both racemic ketamine and esketamine as therapies for psychiatric disorders.

AREAS COVERED

In this article, we conducted a safety review of ketamine and esketamine. In looking at ketamine and esketamine long-term safety effects, we considered data available from experimental studies and several phase-three clinical trials.

EXPERT OPINION

Based on available data, the most common side effects of ketamine/esketamine are generally transient, mild, and self-limited. These include dissociation, nausea, headache, elevated heart rate, and blood pressure. Treatment with esketamine may lead to an increased risk of lower urinary tract symptoms, such as dysuria or urgency. However, severe bladder pathology has not been reported among patients receiving doses of esketamine/ketamine in line with prescribing guidelines for depression. There is considerable data that ketamine at high doses can lead to long-term impairments in cognition. However, the esketamine clinical trials found that cognition generally remains stable or improves over time, suggesting that when used appropriately, there is no increased risk of cognitive impairment.

Research advances in the clinical application of esketamine

Esketamine is dextrorotatory ketamine, which is an enantiomer of ketamine. Compared with ketamine, it has the advantages of a fast metabolism, fewer side effects, and strong pharmacological effects, so it is more suitable for clinical use. Esketamine has a powerful analgesic effect and has little effect on breathing. It has a wide range of applications in the fields of pediatric anesthesia, conscious sedation anesthesia, and emergency analgesia. In addition, it is also used for pain that is difficult to relieve with conventional drugs and to prevent postoperative pain. Various routes of administration are also suitable for patients who need short-term analgesia and sedation. As a drug, esketamine inevitably brings some side effects when it is used clinically. In this article, by introducing the mechanism of action and pharmacological characteristics of esketamine, its clinical application is reviewed, and it provides a reference for the more reasonable and safe clinical application of esketamine.

Post-Marketing Safety Concerns with Esketamine: A Disproportionality Analysis of Spontaneous Reports Submitted to the FDA Adverse Event Reporting System

INTRODUCTION

Esketamine nasal spray received approval for treatment-resistant depression in March 2019.

OBJECTIVE

Using the FDA Adverse Event Reporting System (FAERS) database (March 2019-March 2020), we analysed esketamine-related adverse events (AEs) to detect and characterize relevant safety signals.

METHODS

We used the consolidated case/non-case approach to estimate the reporting odds ratio (ROR) and information component (IC) with relevant confidence intervals (95% CI) for esketamine-related AEs with ≥4 counts. Comparisons between serious and non-serious AEs were performed using non-parametric tests.

RESULTS

The FAERS database contained 962 cases of esketamine-related AEs, with signals detected for several AEs, such as dissociation (ROR = 1,612.64, 95% CI = 1,354.63, 1,919.79; IC = 8.19, 95% CI = 7.96, 8.35), sedation (ROR = 238.46, 95% CI = 202.98, 280.15; IC = 7, 95% CI = 6.75, 7.18), feeling drunk (ROR = 96.17, 95% CI = 61.42, 150.57; IC = 4.84, 95% CI = 4.09, 5.36), suicidal ideation (ROR = 24.03, 95% CI = 18.72, 30.84; IC = 4.31, 95% CI = 3.9, 4.61), and completed suicide (ROR = 5.75, 95% CI = 3.18, 10.41; IC = 2.25, 95% CI = 1.23, 2.94). Signals for suicidal and self-injurious ideation, but not suicide attempt and completed suicide, remained when comparing esketamine to venlafaxine. Females and patients receiving antidepressant polypharmacy, co-medication with mood stabilizers, antipsychotics, benzodiazepines, or somatic medications were more likely to suffer from serious versus non-serious AEs (χ2 = 125.29, p < 0.001, χ2 = 9.08, p = 0.003, χ2 = 8.14, p = 0.004, χ2 = 19.48, p < 0.001, χ2 = 25.62, p < 0.001, and χ2 = 16.79, p < 0.001, respectively).

CONCLUSIONS

Esketamine may carry a clear potential for serious AEs, which deserves urgent clarification by means of further prospective studies.

Efficacy and safety of fixed doses of intranasal Esketamine as an add-on therapy to Oral antidepressants in Japanese patients with treatment-resistant depression: a phase 2b randomized clinical study

BACKGROUND

Esketamine nasal spray (Spravato) in conjunction with oral antidepressants (ADs) is approved in the European Union, United States, and other markets for treatment-resistant depression (TRD). Efficacy, safety, and tolerability of esketamine nasal spray in Japanese patients with TRD needs to be assessed.

METHODS

This Phase 2b, randomized, double-blind (DB), placebo-controlled study was conducted in adult Japanese patients with TRD meeting the Diagnostic and Statistical Manual of Mental Disorders (fifth edition) criteria of major depressive disorder with nonresponse to ≥ 1 but < 5 different ADs in the current episode at screening. Patients were treated with a new oral AD for 6 weeks (prospective lead-in phase); nonresponders were randomized (2:1:1:1) to placebo or esketamine (28-, 56-, or 84-mg) nasal spray along with the continued use of AD for 4 weeks (DB induction phase). Responders (≥50% reduction from baseline in the Montgomery-Asberg Depression Rating Scale [MADRS] total score) from the DB induction phase continued into the 24-week posttreatment phase and patients who relapsed could participate in a 4-week open-label (OL) second induction (flexibly-dosed esketamine). The primary efficacy endpoint, change from baseline in the MADRS total score at Day 28 in the DB induction phase, was based on mixed-effects model using repeated measures pairwise comparisons using a Dunnett adjustment.

RESULTS

Of the 202 patients randomized in the DB induction phase (esketamine [n = 122] or placebo [n = 80]), the MADRS total scores decreased from baseline to Day 28 of the DB induction phase (- 15.2, - 14.5, - 15.1, and - 15.3 for esketamine 28 mg, 56 mg, 84 mg, and placebo groups, respectively), indicating an improvement in depressive symptoms; however, the difference between the esketamine and placebo groups was not statistically significant. The most common treatment-emergent adverse events during the DB induction phase in the combined esketamine group (incidences ranging from 12.3 to 41.0%) were blood pressure increased, dissociation, dizziness, somnolence, nausea, hypoaesthesia, vertigo, and headache; the incidence of each of these events was > 2-fold higher than the corresponding incidence in the placebo group.

CONCLUSIONS

Efficacy of esketamine plus oral AD in Japanese TRD patients was not established; further investigation is warranted. All esketamine doses were safe and tolerated.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02918318 . Registered: 28 September 2016.

The median effective concentration of propofol with different doses of esketamine during gastrointestinal endoscopy in elderly patients: A randomized controlled trial

AIMS

Propofol may result in hypotension, bradycardia and loss of protective reflexes, especially in elderly patients, while esketamine, a N-methyl-D-aspartate receptor antagonist, has analgesic, anaesthetic and sympathomimetic properties and is known to cause less cardiorespiratory depression. We hypothesized that esketamine may reduce the median effective concentration (EC₅₀ ) of propofol and coadministration is less likely to produce hypotension during gastrointestinal endoscopy in elderly patients.

METHODS

Ninety elderly patients, aged 65-89 years, undergoing gastrointestinal endoscopy were randomly assigned into 3 groups: SK0 (control) group (0 mg/kg esketamine); SK0.25 group (0.25 mg/kg esketamine); and SK0.5 group (0.5 mg/kg esketamine). Anaesthesia was achieved by plasma target-controlled infusion of propofol with different bolus doses of esketamine. The EC₅₀ of propofol for gastrointestinal endoscopy was determined by using the up-and-down method of Dixon. The initial plasma target concentration is 2.5 μg/mL and the adjacent concentration gradient is 0.5 μg/mL. Cardiovascular variables were also measured.

RESULTS

Propofol EC₅₀ s and its 95% confidence interval for gastrointestinal endoscopy in elderly patients were 3.69 (2.59-4.78), 2.45 (1.85-3.05) and 1.71 (1.15-2.27) μg/mL in the SK0, SK0.25 and SK0.5 groups, respectively (P < .05). The average percent change from baseline mean arterial pressure was -19.7 (7.55), -15.2 (7.14) and -10.1 (6.73), in the SK0, SK0.25 and SK0.5 groups, respectively (P < .001).

CONCLUSION

Combination medication of propofol with esketamine reduced the propofol EC₅₀ during gastrointestinal endoscopy in elderly patients compared with administration of propofol without esketamine. Increasing doses of SK with propofol are less likely to produce hypotension with shorter recovery time.

Prevention and Management of Common Adverse Effects of Ketamine and Esketamine in Patients with Mood Disorders

The emerging roles of ketamine and esketamine as effective rapid-acting antidepressants hold promise for patients suffering from treatment-resistant depression and/or major depressive disorder with suicidality. Practitioner familiarity with common tolerability/safety concerns along with pragmatic prevention and management strategies are needed to reduce patient burden and improve the acceptability and accessibility of these treatments. The most common treatment-emergent adverse events associated with ketamine/esketamine are dissociation, anxiety, nausea, increased blood pressure, and headache. The majority of side effects are mild, transient, dose dependent, and attenuate with subsequent treatments. Patient selection, baseline physical and psychiatric assessments, and an appropriate setting are critical first steps in the prevention and mitigation of adverse events. Patient education and supportive interventions play central roles in the prevention and management of select adverse events. Severe and/or clinically significant adverse effects may necessitate the judicious use of adjunctive medications. Moreover, practitioners must remain vigilant to the potential for abuse liability and long-term adverse events, for which there are insufficient data. This article succinctly reviews common treatment-emergent adverse events of ketamine and esketamine within the context of mood disorders, and provides practical suggestions for prevention and management at point-of-care.

Ready for a "breakthrough" with ketamine? A look at recent pharmacological insights!

PURPOSE OF REVIEW

To update pharmacological insights on ketamine integrating information from different disciplines for developing steps to "breakthrough" approaches in clinical challenges.

RECENT FINDINGS

Pharmacokinetic/pharmacodynamic (PK/PD) models have incorporated recirculation, ketamine metabolites, drug-drug interaction, and covariates such as age. Ketamine-induced relief from treatment-resistant depression has been explained by "disinhibition" of gamma-aminobutyric acid-ergic interneurons and synaptogenic mechanisms requiring neurotrophic signals. Neuroimaging/electroencephalographic investigations have shown an increase in gamma spectral power in healthy volunteers and patients with depression, but also opposite changes in functional network connectivity after subanesthetic ketamine. Volunteer data may not be transferable to clinical conditions. Altered states of consciousness induced by subanesthetic ketamine have been described by disruption of resisting-state functional networks and frontoparietal connectivity with preservation of multisensory and sensor-motor networks. This has been interpreted as a "disconnected consciousness".

SUMMARY

More precise PK/PD models may improve the ketamine use regimen. The findings from research on depression are an important discovery because ketamine's impact on neuronal plasticity and synaptogenesis in human brain disease has directly been documented. Psychic adverse effects with subanesthetic ketamine are related to a "disconnected consciousness". Overall, progress has been made, but the "breakthrough" still has to come.

Practical recommendations for the management of treatment-resistant depression with esketamine nasal spray therapy: Basic science, evidence-based knowledge and expert guidance

OBJECTIVES

Despite the available therapies for treatment-resistant depression (TRD), there are a limited number that are evidence-based and effective in this hard-to-treat population. Esketamine nasal spray, an intranasal N-methyl-d-aspartate (NMDA) glutamate receptor antagonist, is a novel, fast-acting option in this patient population. This manuscript provides expert guidance on the practicalities of using esketamine nasal spray.

METHODS

A group of six European experts in major depressive disorder (MDD) and TRD, with clinical experience of treating patients with esketamine nasal spray, first generated practical recommendations, before editing and voting on these to develop consensus statements during an online meeting.

RESULTS

The final consensus statements encompass not only pre-treatment considerations for patients with TRD, but also specific guidelines for clinicians to consider during and post-administration of esketamine nasal spray.

CONCLUSIONS

Esketamine nasal spray is a novel, fast-acting agent that provides an additional treatment option for patients with TRD who have previously failed several therapies. The guidance here is based on the authors' experience and the available literature; however, further real-world use of esketamine nasal spray will add to existing knowledge. The recommendations offer practical guidance to clinicians who are unfamiliar with esketamine nasal spray.

Rapid Onset of Intranasal Esketamine in Patients with Treatment Resistant Depression and Major Depression with Suicide Ideation: A Meta-Analysis

Objective

We performed a meta-analysis of randomized double-blinded placebo controlled trials (DB-RCTs) to investigate efficacy and safety of intranasal esketamine in treating major depressive disorder (MDD) including treatment resistant depression (TRD) and major depression with suicide ideation (MDSI).

Methods

Mean change in total scores on Montgomery-Åsberg Depression Rating Scale (MADRS) from baseline to different time-points were our primary outcome measure. Secondary efficacy measures included rate of remission of depression and resolution of suicidality.

Results

Eight DB-RCTs (seven published and one un-published) covering 1,488 patients with MDD were included. Esketamine more significantly improved MADRS total scores than placebo starting from 2-4 hours after the first administration (standardized mean difference, -0.41 [95% CI, -0.58 to -0.25], p < 0.00001), and this superiority maintained until end of double-blinded period (28 days). Sub-group analysis showed that superior antidepressant effects of esketamine over placebo in TRD and MDSI was observed from 2-4 hours, which was maintained until 28 days. Resolution of suicide in MDSI was also greater for esketamine than for placebo at 2-4 hours (OR of 2.04, 95% CIs, 1.37 to 3.05, p = 0.0005), but two groups did not statistically differ at 24 hours and day 28. Total adverse events (AEs), and other common AEs including dissociation, blood pressure increment, nausea, vertigo, dysgeusia, dizziness, and somnolence were more frequent in esketamine than in placebo group.

Conclusion

Esketamine showed rapid antidepressant effects in patients with MDD, including TRD and MDSI. The study also suggested that esketamine might be associated with rapid anti-suicidal effects for patients with MDSI.

Synthesizing the Evidence for Ketamine and Esketamine in Treatment-Resistant Depression: An International Expert Opinion on the Available Evidence and Implementation

Replicated international studies have underscored the human and societal costs associated with major depressive disorder. Despite the proven efficacy of monoamine-based antidepressants in major depression, the majority of treated individuals fail to achieve full syndromal and functional recovery with the index and subsequent pharmacological treatments. Ketamine and esketamine represent pharmacologically novel treatment avenues for adults with treatment-resistant depression. In addition to providing hope to affected persons, these agents represent the first non-monoaminergic agents with proven rapid-onset efficacy in major depressive disorder. Nevertheless, concerns remain about the safety and tolerability of ketamine and esketamine in mood disorders. Moreover, there is uncertainty about the appropriate position of these agents in treatment algorithms, their comparative effectiveness, and the appropriate setting, infrastructure, and personnel required for their competent and safe implementation. In this article, an international group of mood disorder experts provides a synthesis of the literature with respect to the efficacy, safety, and tolerability of ketamine and esketamine in adults with treatment-resistant depression. The authors also provide guidance for the implementation of these agents in clinical practice, with particular attention to practice parameters at point of care. Areas of consensus and future research vistas are discussed.

Depression: Biological markers and treatment

Nowadays depression is considered as a systemic illness with different biological mechanisms involved in its etiology, including inflammatory response, hypothalamic-pituitary-adrenal (HPA) axis dysregulation and neurotransmitter and neurotrophic systems imbalance. Novel "omics" approaches, such as metabolomics and glycomics provide information about altered metabolic pathways and metabolites, as well as disturbances in glycosylation processes affected by or causing the development of depression. The clinical diagnosis of depression continues to be established based on the presence of the specific symptoms, but due to its heterogeneous underlying biological background, that differs according to the disease stage, there is an unmet need for treatment response biomarkers which would facilitate the process of appropriate treatment selection. This paper provides an overview of the role of major stress response system, the HPA axis, and its dysregulation in depression, possible involvement of neurotrophins, especially brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor and insulin-like growth factor-1, in the development of depression. Article discusses how activated inflammation processes and increased cytokine levels, as well as disturbed neurotransmitter systems can contribute to different stages of depression and could specific metabolomic and glycomic species be considered as potential biomarkers of depression. The second part of the paper includes the most recent findings about available medical treatment of depression. The described biological factors impose an optimistic conclusion that they could represent easy obtainable biomarkers potentially predicting more personalized treatment and diagnostic options.

Cardiovascular effects of repeated subanaesthetic ketamine infusion in depression

BACKGROUND

Ketamine produces significant rapid-onset and robust antidepressant effects in patients with major depressive disorder. However, this drug also has transient cardiovascular stimulatory effects, and there are limited data about potential predictors of these cardiovascular effects.

METHODS

A total of 135 patients with unipolar and bipolar depression received a total of 741 ketamine infusions (0.5 mg/kg over 40 min). Blood pressure and pulse were monitored every 10 min during the infusions and 30 min after the infusions. Depressive, psychotomimetic and dissociative symptom severity was assessed at baseline and 4 hours after each infusion.

RESULTS

The maximum blood pressure and pulse values were observed at 30-40 min during infusions. The largest mean systolic/diastolic blood pressure increases were 7.4/6.0 mmHg, and the largest mean pulse increase was 1.9 beats per min. No significant change in blood pressure and pulse was found in the second to sixth infusions compared with the first infusion. Patients who were older (age⩾50 years), hypertensive and receiving infusions while exhibiting dissociative symptoms showed greater maximal changes in systolic and diastolic blood pressure than patients who were younger (age<50 years), normotensive and without dissociative symptoms (all p < 0.05). Hypertensive patients had less elevation of pulse than normotensive patients (p < 0.05). Ketamine dosage was positively correlated with changes in systolic and diastolic blood pressure (all p < 0.05).

CONCLUSIONS

Blood pressure and pulse elevations following subanaesthetic ketamine infusions are transient and do not cause serious cardiovascular events. Older age, hypertension, large ketamine dosage and dissociative symptoms may predict increased ketamine-induced cardiovascular effects.

Repeated subcutaneous esketamine for treatment-resistant depression: Impact of the degree of treatment resistance and anxiety comorbidity

BACKGROUND

A large number of studies indicate that subanesthetic doses of ketamine induce a fast antidepressant effect. Limited studies have investigated the subcutaneous (SC) route, and it remains unclear for whom this treatment is most suitable.

AIMS

The aim of this study was to examine the effect on depressive symptoms of repeated subanesthetic doses of SC esketamine in unipolar and bipolar treatment-resistant depression (TRD) and clinical predictors of response.

METHODS

A retrospective analysis of 70 patients who received six SC esketamine doses weekly as an adjunctive treatment was carried out. Doses started at 0.5 mg/kg and it could be titrated up to 1 mg/kg, according to response. The primary outcome was reduction in depressive symptoms. Statistical analysis to investigate clinical predictors of effectiveness included logistic regression analysis using a dependent variable of a 50% reduction in rating scale scores at the end of treatment. Comparisons between groups were made through analysis of variance and treatment effects.

RESULTS

At baseline, our sample presented with severe treatment resistance in 65.7%, as assessed by the Maudsley Staging Method (MSM), and 47.1% had anxiety disorder comorbidity. The response rate was 50%. A better outcome was predicted by mild and moderate MSM scores (OR = 3.162, p = 0.041) and anxiety disorder comorbidity (OR = 3.149, p = 0.028).

CONCLUSIONS

Our results suggest that higher levels of treatment resistance may be associated with a poor response to SC esketamine. Unlike traditional pharmacotherapies, it might benefit those with poor prognosis such as patients with depression and comorbid anxiety. Therefore, future research could investigate whether esketamine should receive a more prominent place in the treatment algorithm for TRD.

Effects of subcutaneous esketamine on blood pressure and heart rate in treatment-resistant depression

INTRODUCTION AND OBJECTIVES

The impact of multiple subcutaneous (s.c.) esketamine injections on the blood pressure (BP) and heart rate (HR) of patients with unipolar and bipolar treatment-resistant depression (TRD) is poorly understood. This study aimed to assess the cardiovascular safety of multiple s.c. doses of esketamine in patients with TRD.

METHODS

Seventy TRD patients received 394 weekly s.c. esketamine injections in conjunction with oral antidepressant therapy for up to six weeks. Weekly esketamine doses were 0.5, 0.75 or 1.0 mg/kg according to each patient's response to treatment. Participants were monitored before each treatment and every 15 minutes thereafter for 120 minutes. We assessed systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR measurements for the entire treatment course.

RESULTS

BP increased after the first s.c. esketamine injection, reaching maximum mean SBP/DBP levels of 4.87/5.54 mmHg within 30-45 minutes. At the end of monitoring, 120 minutes post dose, vital signs returned to pretreatment levels. We did not detect significant differences in BP between doses of 0.5, 0.75, and 1 mg/kg esketamine. Mean HR did not differ significantly between doses or before and after s.c. esketamine injection.

CONCLUSIONS

The BP changes observed with repeated s.c. esketamine injections were mild and well tolerated for doses up to 1 mg/kg. The s.c. route is a simple and safe method of esketamine administration, even for patients with clinical comorbidities, including obesity, hypertension, diabetes, and dyslipidemia. However, 14/70 patients experienced treatment-emergent transient hypertension (SBP >180 mmHg and/or a DBP >110 mmHg). Therefore, we strongly recommend monitoring BP for 90 minutes after esketamine dosing. Since s.c. esketamine is cheap, requires less frequent dosing (once a week), and is a simpler procedure compared to intravenous infusions, it might have an impact on public health.

Psychiatric Medications and Hypertension

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of psychiatric medications that impact blood pressure in adult patients either as a direct side effect or indirectly, via negative metabolic impact or interactions with other medications. In addition, pertinent interactions between psychiatric medications and antihypertensive agents will be discussed.

RECENT FINDINGS

Although the novel intranasal antidepressant, esketamine, has been shown to increase blood pressure shortly after dosing, treatment with antihypertensive medications is not typically required. In addition, no increase in serious adverse cardiac events was reported with this medication. The negative metabolic impact of antipsychotic medications has been shown to occur within the first month of treatment and necessitates early monitoring. When compared with the general population with cardiovascular disease, mortality risk in patients with severe and persistent psychiatric illness is higher, and death occurs 10 years earlier. There are several psychiatric treatments that increase blood pressure directly as well as indirectly, via negative metabolic impact and drug/diet interactions. Fortunately, there are no absolute contraindications for use of any psychiatric medication in patients with pre-existing hypertension. Given data which suggests that patients diagnosed with more severe psychiatric disorders are known to receive inadequate medical care for hypertensive illness and experience increased mortality risk from cardiovascular disease, it is important for all physicians to be aware of the increased risk in this population and for both thorough assessment and treatment to occur.

Metabolic Risk Factors and Cardiovascular Safety in Ketamine Use for Treatment Resistant Depression

INTRODUCTION

Ketamine exhibits antidepressant properties in treatment-resistant depression (TRD) with some concern over its cardiovascular safety and tolerability issues. This paper reports on the cardiovascular safety in short-term intravenous ketamine treatment in TRD inpatients with major depressive disorder (MDD) and bipolar disorder (BP).

MATERIALS AND METHODS

The observational study population comprises 35 MDD and 14 BP subjects treated with intravenous ketamine.

RESULTS

Blood pressure (RR) and heart rate (HR) values returned to baseline within 1.5-hours post infusion with no sequelae for all study subjects. Six time points were analyzed for each infusion: 0', 15', 30', 45', 60' and 90' for RR and HR. After the infusion significant peaks in systolic (p = 0.004) and diastolic (p = 0.038) RR were seen. In concomitant medication with selective serotonin reuptake inhibitors (SSRIs), higher RR peaks (p = 0.020; p = 0.048) were seen as compared to other subjects. The decrease in HR was greater (p = 0.02) in the absence of concomitant medication with mood stabilizers as compared to subjects receiving mood stabilizing medication accompanied by the observation of a greater decrease in diastolic RR among those taking mood stabilizers (p = 0.009).

LIMITATIONS

The study may be underpowered due to the small sample size. The observations apply to an inhomogeneous TRD population in a single-site, pilot study, with no blinding and are limited to the acute administration.

CONCLUSION

The study demonstrates good safety and tolerability profile of intravenous ketamine as add-on intervention to current psychotropic medication in TRD, regardless of the MDD or BP type of mood disorders. The abatement of elevated RR and BP scores was observed in time with no sequelae nor harm. Still, cardiovascular risks appear to be more pronounced in subjects with comorbid arterial hypertension and diabetes mellitus.