Clinical specificity profile for novel rapid acting antidepressant drugs

Xenon gas as a potential treatment for opioid use disorder, alcohol use disorder, and related disorders

Xenon gas is considered to be a safe anesthetic and imaging agent. Research on its other potentially beneficial effects suggests that xenon may have broad efficacy for treating health disorders. A number of reviews on xenon applications have been published, but none have focused on substance use disorders. Accordingly, we review xenon effects and targets relevant to the treatment of substance use disorders, with a focus on opioid use disorder and alcohol use disorder. We report that xenon inhaled at subsedative concentrations inhibits conditioned memory reconsolidation and opioid withdrawal symptoms. We review work by others reporting on the antidepressant, anxiolytic, and analgesic properties of xenon, which could diminish negative affective states and pain. We discuss research supporting the possibility that xenon could prevent analgesic- or stress-induced opioid tolerance and, by so doing could reduce the risk of developing opioid use disorder. The rapid kinetics, favorable safety and side effect profiles, and multitargeting capability of xenon suggest that it could be used as an ambulatory on-demand treatment to rapidly attenuate maladaptive memory, physical and affective withdrawal symptoms, and pain drivers of substance use disorders when they occur. Xenon may also have human immunodeficiency virus and oncology applications because its effects relevant to substance use disorders could be exploited to target human immunodeficiency virus reservoirs, human immunodeficiency virus protein-induced abnormalities, and cancers. Although xenon is expensive, low concentrations exert beneficial effects, and gas separation, recovery, and recycling advancements will lower xenon costs, increasing the economic feasibility of its therapeutic use. More research is needed to better understand the remarkable repertoire of effects of xenon and its potential therapeutic applications.

Understanding and treating postpartum depression: a narrative review

Postpartum depression (PPD) is an increasingly prevalent but still poorly characterized disorder. Causal and modulating factors include hormones fluctuations, such as estrogen, progesterone, and allopregnolone, pathways imbalances, such as oxytocin and kynurenine, chronobiological factors, and brain imaging alterations. Treatment may differ from the traditional major depression management, while selective serotonin reuptake inhibitors such as sertraline are commonly used and suggested by guidelines, neurosteroids such as brexanolone and the more convenient zuranolone have been recently approved. Newer neurosteroids such as ganaxolone, valaxanolone, and lysaxanolone are currently under development, but also esketamine and psychedelics are promising potential treatments. Other somatic treatments including brain stimulation techniques and light therapy also showed benefit. PPD is therefore increasingly understood as, at least partially, independent from major depressive disorder. Specific and individualized treatments including pharmacological and non-pharmacological therapies are progressively being introduced in the routine clinical practice.

Specific symptomatology profile associated with treatment resistant depression: A multicentric study from the Group for the Study of Resistant Depression with a focus on sex

BACKGROUND

Clinical predictors of treatment-resistant depression could improve treatment strategies. Depressive symptom profiles at baseline are potential outcome predictors, but little evidence is available, and sex-specific profiles have been scarcely investigated.

METHODS

Baseline symptom scores of 1294 patients with major depressive disorder were assessed by the Montgomery-Åsberg depression rating scale (MADRS) as part of a multicenter study by the "Group for the Studies of Resistant Depression". Treatment outcomes were assessed according to the MADRS after ≥4 weeks of naturalistic treatment. We tested if individual MADRS item scores at baseline were associated with treatment outcome in the whole sample and in sex-stratified subgroups.

RESULTS

A specific baseline symptom profile was associated with non-response in the whole sample. In particular, apparent and reported sadness, reduced sleep, lassitude, inability to feel, and pessimistic thoughts were the only MADRS items that scored higher at baseline in patients with subsequent lack of response. In the sex-stratified analysis, females showed a similar profile overall, however they showed higher baseline levels of inner tension, inability to feel, and pessimistic thoughts compared to males, and these symptoms were associated with lack of response in females but not in males. Neurovegetative symptoms were poorly predictive. Overall baseline severity related to poor response.

LIMITATIONS

This is a post-hoc analysis. The naturalistic design of the study with a retrospective assessment is potential limitations.

CONCLUSION

A specific baseline symptom profile characterized by higher sadness, reduced sleep and anhedonic features may be indicative of poor treatment outcome. Females showed a distinctive baseline profile associated with poor response.

Anhedonia: Current and future treatments

Anhedonia is a transdiagnostic domain that leads to poor disorder outcome and low remission rates. This narrative review describes a broad range of interventions targeting anhedonia, including pharmacological, neuromodulatory, behavioral, and lifestyle-based approaches. Drugs such as vortioxetine, agomelatine, bupropion, ketamine, and brexpiprazole show promising anti-anhedonic effects, while traditional antidepressants, such as serotonin-norepinephrine reuptake inhibitors (SNRIs) and, even more so, selective serotonin reuptake inhibitors (SSRIs), are less effective. Neuromodulation techniques, including repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and transcutaneous auricular vagus nerve stimulation, proved effective at improving anhedonia, particularly when used in targeted areas. Psychotherapeutic interventions, including behavioral activation, mindfulness-based strategies, and savoring techniques, also help re-engage patients with pleasurable activities and enhance positive affect. Innovative treatments, such as aticaprant and psilocybin, showed promising results. Substantial evidence suggests that improving anhedonia leads to better psychosocial functioning, quality of life, and sustained remission. Although most data come from short-term studies, several long-term analyses suggest that maintaining hedonic improvements is feasible and beneficial. The reviewed evidence underscores the importance of routine assessment of anhedonia and the integration of symptom-specific strategies. Tailoring interventions to address individual patterns of reward disruption may optimize outcomes for patients with anhedonia.

Is Pilates effective in improving depressive disorders? A comprehensive overview

Depressive disorders are disabling conditions that account for high social costs. Pilates demonstrated to have several beneficial effects on health. Objective of this manuscript was to systematically review the literature about the effects of Pilates on depressive disorders. A bibliographic search was conducted in the main database sources (Pubmed, Medline, and Scopus). The inclusion criteria consisted of articles written in English language about the effectiveness of Pilates on depressive symptoms. Most of included studies are randomized controlled trials (10 out of 12). The available literature agrees in indicating that Pilates is effective in improving depressive symptoms especially when compared to inactivity and when this practice is administered for a medium-long period (8-16 weeks). In addition, Pilates seems to have at least comparable effectiveness than aerobic exercise. Pilates can be considered a reliable complementary treatment for people with depressive disorders. These findings should be interpreted considering the different types of practice administered as well as the different duration of the programs or rating scales used to assess mood symptoms. Studies with a more homogenous design are needed to confirm and make generalizable the results presented in this review.

Unlocking the Link Between Gut Microbiota and Psychopathological Insights in Anorexia Nervosa: A Systematic Review

OBJECTIVE

This systematic review explores the associations between qualitative/quantitative changes in gut microbiota and psychopathological symptoms or other clinical features in patients with eating disorders (EDs). Secondary outcomes include exploring gut microbiota changes in EDs and potential relationships with psychotropic drug use.

METHOD

A systematic search was conducted across biomedical databases from inception to June 2024 according to PRISMA guidelines. The risk of bias was assessed, and a narrative synthesis was performed due to the heterogeneity of the outcomes.

RESULTS

Only findings related to anorexia nervosa (AN) were identified. Ten studies, of which seven were longitudinal, two cross-sectional, and one interventional (N = 350 patients with AN, and 304 HCs), were included. Despite no clear links between diversity metrics and clinical symptoms being observed, specific taxa belonging to phylum Firmicutes, such as Clostridium, Roseburia, Lactobacillus, Faecalibacterium, and Bifidobacterium belonging to Actinobacteriota correlated with ED psychopathology, including anxiety and depressive symptoms.

CONCLUSIONS

Changes in microbiota were related to anxiety and depressive symptoms, as well as altered eating behaviours by modulating inflammation and insulin pathways through short-chain fatty acids (SCFAs), that also lead to neurotransmitter imbalances. Further studies are required to replicate these finding and to explore whether similar patterns are observed in other EDs.

Hypomanic symptoms in major depressive disorder: Prognostic impact and treatment issues

BACKGROUND

Mixed depression (MXD), defined as (hypo)manic symptoms occurring within major depressive episodes, is common in both bipolar and unipolar disorders, but its prognostic and treatment implications remain unclear. This study aimed to examine the relationship between hypomanic symptoms, treatment response and remission of suicidal thoughts.

METHODS

We analyzed 1243 adults with major depressive disorder (MDD), recruited for a naturalistic study on treatment-resistant depression. Data were gathered cross-sectionally and retrospectively through structured interviews and clinical rating scales including the Young Mania Rating Scale (YMRS) and Montgomery-Asberg Depression Rating Scale (MADRS); statistical analyses were performed using univariate and multivariate methods.

RESULTS

Hypomanic symptoms were present in 651 patients (45 %), while 307 patients (25 %) responded to treatment. Both treatment responders (p < 0.0001) and those who achieved remission from suicide ideation (p = 0.0085) showed lower hypomanic (YMRS) scores. Multivariate analysis showed that hypomanic symptoms were negatively linked to treatment response (O.R. 0.71-0.87), while bipolar spectrum markers such as age at illness onset (O.R. 1.00-1.03) and MDD recurrence (O.R. 0.47-0.89) predicted remission from suicidal thoughts. Medications commonly used to treat bipolar disorder showed some benefits, with dopamine/serotonin antagonists improving suicide ideation (p < 0.0001) and mood stabilizers being associated with reduced hypomanic symptoms (p = 0.0003).

LIMITATIONS

The study lacked prospective clinical assessments and treatment randomization.

CONCLUSION

Hypomanic symptoms are common in unipolar depression; their assessment is essential to identify challenging-to-treat cases and select the best pharmacological options.

The revival of psilocybin between scientific excitement, evidence of efficacy, and real-world challenges

The revival of psilocybin in psychopharmacological research heralds a potential paradigm shift for treating mood and anxiety disorders, and other psychiatric conditions beyond the psychotic spectrum. This critical review evaluates current evidence on psilocybin's efficacy, juxtaposing potential benefits with the practical aspects of psychedelic-assisted psychotherapy (PAP) and the methodological constraints of existing research.An electronic literature search was conducted using PubMed/MEDLINE, selecting studies published up to December 2023 that explored the clinical use of psilocybin in mood and anxiety disorders, obsessive-compulsive disorder, post-traumatic stress disorder, and substance use disorder. Despite promising preliminary results suggesting psilocybin's efficacy in alleviating depression and anxiety, as well as obsessions, compulsions, and addictive behaviors, significant evidence gaps persist. These include evaluating the efficacy of psilocybin compared to standard antidepressants or anxiolytic molecules and identifying patient subpopulations that might benefit most from PAP. Concerns about psilocybin's safety, long-term efficacy, and optimal dosage remain unclear due to previous trials' limitations. Real-world implementation faces challenges, including infrastructural requirements, personnel training, and unresolved legal and ethical issues. This paper argues for further research to substantiate the evidence base, emphasizing the need for larger studies that overcome current methodological limitations and explore psilocybin's full therapeutic potential. While psilocybin holds promise for psychiatry, its successful translation from research to clinical practice demands more robust evidence on efficacy, safety, and methodological rigor. In addition, other factors, such as cultural stigma and legal/ethical issues, need to be successfully addressed to facilitate psilocybin's implementation in healthcare systems.

Anhedonia is associated with a specific depression profile and poor antidepressant response

BACKGROUND

Anhedonic features within major depressive disorder (MDD) have been associated with worse course and outcome and may predict nonresponse to treatment. However, a detailed clinical profile of anhedonia in MDD is still lacking.

MATERIALS AND METHODS

One thousand two hundred ninety-four patients with MDD were selected from the cross-sectional European multicenter Group for the Study of Resistant Depression study. Anhedonia was assessed through the Montgomery-Åsberg Depression Rating Scale anhedonia item "inability to feel." Clinical and demographic features were then analyzed.

RESULTS

The presence of anhedonia related to a distinct demographical (living alone) and clinical profile (thyroid diseases, diabetes, suicide risk, high number of previous depressive episodes, more severe MDD, and more frequent inpatient status). Furthermore, anhedonia was associated with nonresponse to treatment and treatment resistance, even after adjusting for confounding variables.

CONCLUSIONS

Our findings support the role of anhedonia as a modulating feature of MDD, being associated with a more severe depression profile. Moreover, anhedonic features are independent predictors of poor treatment response.

The emergence of antidepressant drugs targeting GABAA receptors: A concise review

Depression is among the most common psychiatric illnesses, which imposes a major socioeconomic burden on patients, caregivers, and the public health system. Treatment with classical antidepressants (e.g. tricyclic antidepressants and selective serotonine reuptake inhibitors), which primarily affect monoaminergic systems has several limitations, such as delayed onset of action and moderate efficacy in a relatively large proportion of depressed patients. Furthermore, depression is highly heterogeneus, and its different subtypes, including post-partum depression, involve distinct neurobiology, warranting a differential approach to pharmacotherapy. Given these shortcomings, the need for novel antidepressants that are superior in efficacy and faster in onset of action is fully justified. The development and market introduction of rapid-acting antidepressants has accelerated in recent years. Some of these new antidepressants act through the GABAergic system. In this review, we discuss the discovery, efficacy, and limitations of treatment with classic antidepressants. We provide a detailed discussion of GABAergic neurotransmission, with a special focus on GABAA receptors, and possible explanations for the mood-enhancing effects of GABAergic medications (in particular neurosteroids acting at GABAA receptors), and, ultimately, we present the most promising molecules belonging to this family which are currently used in clinical practice or are in late phases of clinical development.

The role of psilocybin in depressive disorders

Depression is a serious psychiatric disorder with a high incidence of morbidity and mortality and psilocybin with psychotherapy has emerged as a promising potential in the treatment of depressive disorders. A review of psilocybin use in patients with depressive disorders is presented.A search was conducted investigating the use of psilocybin in patients with depressive disorders and treatment resistant depression via PubMed/MEDLINE, EMBASE, and Google Scholar in October 2023; all publication types were permitted and limited for English-language. Keyword search terms included: "psilocybin" or "psychedelics" and "depression", or "major depressive disorder", or "treatment-resistant depression". Controlled and uncontrolled clinical trials utilizing psilocybin with psychological support for major depressive disorder and treatment-resistant depression, as well as in patients with depression and cancer related anxiety have demonstrated immediate and sustained antidepressant and anxiolytic effects. Psilocybin has a favorable safety profile and was well-tolerated in clinical trials. Psilocybin's abuse potential is low and clinical research suggests the potential of psilocybin to produce rapid and lasting antidepressant effects up to 12 months post-treatment. Psilocybin may offer a valuable contribution as an option to the currently available pharmacological and psychotherapeutic agents for patients with major depressive disorders, treatment-resistant depression as well as for patients with depression and comorbid terminal cancer. Future studies are needed to demonstrate these findings and any synergistic interaction between psilocybin and the psychological support offered to patients during sessions.

Pediatric suicide: Review of a preventable tragedy

Concepts of suicide are explored in this issue with a focus on suicide in children and adolescents. The epidemiology of pediatric suicide in the United States is reviewed; also, risk and protective factors, as well as prevention strategies, are discussed. Suicide in the pediatric athlete and the potential protective effect of exercise are examined. In addition, this analysis addresses the beneficial role of psychological management as well as current research on pharmacologic treatment and brain stimulation procedures as part of comprehensive pediatric suicide prevention. Though death by suicide in pediatric persons has been and remains a tragic phenomenon, there is much that clinicians, other healthcare professionals, and society itself can accomplish in the prevention of pediatric suicide as well as the management of suicidality in our children and adolescents.

Cognitive Dysfunction in Unipolar Depression

Background

Cognitive dysfunctions play a critical role in the psychopathology of depression. They regulate various psychosocial and functional outcomes and affect workplace functionality, productivity, and relapses. An objective evaluation of affected cognitive domains is germane in understanding the relapses and functional recovery in depression. Thus, to know cognitive dysfunctions beyond affective biases, this study was conducted to compare the cognitive functions of drug-naïve patients with unipolar depression with healthy matched controls.

Methods

Fifty patients diagnosed with unipolar depression as per the International Classification of Diseases, tenth revision: Diagnostic Criteria for Research (Depressive Episode and Recurrent Depressive Disorder) and 50 healthy controls were enrolled on an outpatient basis from January 2022 to June 2023. Cases were regrouped as mild, moderate, and severe based on Beck's Depression Inventory (BDI-II). A battery of tests assessed the cognitive functions: Wisconsin Card Sorting Test, Trail Making Test, Visual Retention subtests of PGI Battery of Brain Dysfunction, Digit Span, and Verbal Memory. The Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire was used for a subjective assessment of cognitive functioning.

Results

The sociodemographic characteristics of cases and controls did not differ significantly. However, within-group and between-group analyses revealed significantly lower performance of cases compared to controls. Cognitive impairment was positively correlated with BDI-II scores.

Conclusion

Depression is associated with dysfunction in the domains of planning, attention, sustained attention, and visual and verbal memory. This dysfunction is independent of cognitive and affective bias and may exist even after clinical remission.

A Critical View on New and Future Antidepressants

For the first time after many decades, many new antidepressants have been approved and many more are under various stages of development and will soon be available in the market. The new drugs present a range of new mechanisms of action with benefits in terms of speed of action, tolerability and range of treatable disorders. Neurosteroids have been recently approved and their rapid benefit may extend from postpartum depression to anxious depression and bipolar depression, dextromethorphan and bupropion combination may prove useful in major depression but also in treatment resistant depression, dextromethadone is a possible augmentation in partial antidepressant response, psychedelic drugs have the potential of long lasting benefits after a single administration, though are still experimental treatments. Botulinum has the same advantage of psychedelics of a single administration and its antidepressant effects may last for weeks or more. Further potentially interesting new antidepressant mechanisms include new drug targets, drug repurposing and genetic or epigenetic manipulations. It is therefore important that clinicians are kept up to date with new evidence so that new evidence can be rapidly translated into clinical practice.

Zuranolone for treatment of major depressive disorder: a systematic review and meta-analysis

Background

Current treatment modalities for Major Depressive Disorder have variable efficacies and a variety of side effects. To amend this, many trials for short term, well tolerated monotherapies are underway. One such option is Zuranolone (SAGE-217), which is a recent FDA approved antidepressant for Post Partum depression (PPD) and is undergoing clinical trials for PPD, major depressive disorder (MDD) and essential tremors (ET).

Objectives

Pool currently available data that compare Zuranolone to Placebo for the treatment of Major Depressive Disorder and evaluate its efficacy and safety profile.

Methods

We retrieved data from PUBMED and SCOPUS from inception to July 2023. We included articles comparing Zuranolone or SAGE 217 with placebo in patients suffering from Major Depressive Disorder. Review Manager 5.4 was used to analyze the outcomes including changes in the Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A) and Montgomery-Åsberg Depression Rating Scale (MADRS) scores from baseline as well as any treatment emergent adverse events (TEAEs) and severe adverse events.

Results

Our review analyzed 4 trials and the data of 1,357 patients. Patients treated with Zuranolone indicated a statistically significant effect in the change from baseline in HAM-D score (p = 0.0009; MD [95% CI]: -2.03 [-3.23, -0.84]) as well as in MADRS score (p = 0.02; MD [95% CI]: -2.30[-4.31, -0.30]) and HAM-A score (p = 0.03; MD [95% CI]: -1.41[-2.70, -0.11]) on 15th day when compared to the Placebo group. Zuranolone was also significantly associated with a higher response rate (p = 0.0008; OR [95% CI]: 1.63[1.14, 2.35]) and higher remission rate (p = 0.03; OR [95% CI]: 1.65[1.05, 2.59]) when compared with the placebo. As for safety, Zuranolone was significantly associated with 1 or more TEAE (p = 0.006; RR [95% CI]: 1.14[1.04, 1.24]) but an insignificant association with side effects that lead to drug discontinuation (p = 0.70; RR [95% CI]: 1.18[0.51, 2.76]) and serious adverse events (p = 0.48; RR [95% CI]: 1.46 [0.52, 4.10]) when compared with placebo.

Conclusion

Zuranolone is an effective and safe drug for short course major depressive disorder monotherapy. It shows results in 14 days (compared to 2-4 weeks that SSRI's take) and has anti-anxiolytic effects as well. However, only 4 trials have been used for the analysis and the sample size was small. The trials reviewed also cannot determine the long-term effects of the drug. More trials are needed to determine long term effects.

Chinese herbal medicines for the treatment of depression: a systematic review and network meta-analysis

Objectives: Amidst rising global burden of depression and the associated challenges with conventional antidepressant therapies, there is a growing interest in exploring the efficacy and safety of alternative treatments. This study uses a Bayesian network meta-analysis to rigorously evaluate the therapeutic potential of Chinese herbal medicines in the treatment of depression, focusing on their comparative efficacy and safety against standard pharmacological interventions. Methods: Five databases (PubMed, Wanfang Data, EMBASE, CNKI, and the Cochrane Library) and grey literature were searched from inception to end of July 2023 to identify studies that assessed the efficacy and safety of Chinese herbal medicines in treating depression. The response rate, Hamilton Depression Scale (HAMD) scores, and rates of adverse events were assessed through both direct and indirect comparisons. Data extraction and risk of bias assessment were meticulously performed. Statistical analysis used Markov chain Monte Carlo methods, with effect size estimates provided as odd ratios and their 95% confidence intervals. Results: A total of 198 RCTs involving 8,923 patients were analyzed, assessing 17 Chinese herbal medicines. Surface Under the Cumulative Ranking results indicated that the top three treatments with the best response rate were possibly Guipiwan, Ease Pill, and Chaihu Jia Longgu Muli Decoction; the top three treatments on the reduction of HAMD scores were Chai Hu Shu Gan San, Xingnao Jieyu Decoction, and Xiaoyao Powder; and the top three treatments with the lowest adverse effects rates were Xiaoyao Powder, Alprazolam, and Xingnao Jieyu Decoction. Interestingly, commonly used synthetic drugs such as Fluoxetine, Escitalopram, Amitriptyline, Sertraline, Flupentixol and Melitracen, and Venlafaxine, not only appeared to be less effective than specific Chinese herbal medicines (Gan Mai Da Zao Decoction, Chaihu Jia Longgu Muli Decoction, Chai Hu Shu Gan San, Danzhi-Xiaoyao-San, and Xingnao Jieyu Decoction), but they were also related to substantially higher risk of adverse events. Conclusion: Our findings elucidate the promising therapeutic potential of Chinese herbal medicines as viable alternatives in the treatment of depression, with certain herbs demonstrating enhanced efficacy and safety profiles. The outcomes of this study advocate for the integration of these alternative modalities into contemporary depression management paradigms. However, it underscores the necessity for larger, methodologically robust trials to further validate and refine these preliminary findings. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023452109.

Astrocytic GABAergic Regulation in Alcohol Use and Major Depressive Disorders

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS). Most GABAergic neurons synthesize GABA from glutamate and release it in the synaptic cleft in the CNS. However, astrocytes can also synthesize and release GABA, activating GABA receptors in the neighboring neurons in physiological and pathological conditions. As the primary homeostatic glial cells in the brain, astrocytes play a crucial role in regulating GABA homeostasis and synaptic neurotransmission. Accumulating evidence demonstrates that astrocytic GABA dysregulation is implicated in psychiatric disorders, including alcohol use disorder (AUD) and major depressive disorder (MDD), the most prevalent co-occurring psychiatric disorders. Several current medications and emerging pharmacological agents targeting GABA levels are in clinical trials for treating AUD and MDD. This review offers a concise summary of the role of astrocytic GABA regulation in AUD and MDD. We also provide an overview of the current understanding and areas of debate regarding the mechanisms by which astrocytes regulate GABA in the CNS and their potential significance in the molecular basis of AUD and MDD, paving the way toward future research directions and potential therapeutic target areas within this field.

Dextromethorphan/Bupropion: A Novel Treatment for Patients With Major Depressive Disorder

BACKGROUND

Major depressive disorder (MDD) affects millions of people and is the leading cause of disability worldwide. Patients report decreased quality of life and ability to perform activities of daily living. It is estimated that the current standard of care, which includes pharmacologic therapy with a selective serotonin reuptake inhibitor, is effective in 40%-60%. Additional treatment options are warranted. The combination of dextromethorphan (DEX) and bupropion (BUP) (Auveulty) was approved for treatment in 2022. This unique combination offers an interesting mechanism of action and favorable onset of action for patients with MDD.

PHARMACODYNAMICS AND PHARMACOKINETICS

The mechanism of action of DEX-BUP when used in combination is unique. DEX is a noncompetitive N-methyl-d-aspartate receptor antagonist rapidly metabolized through the CYP450 2D6. BUP is an aminoketone and CYP2D6 inhibitor, which results in increased plasma levels of DEX through competitive CYP2D6 inhibition.

CLINICAL TRIALS

In a phase 2 clinical study, the efficacy of DEX-BUP was compared with BUP alone in patients with clinically diagnosed MDD. At baseline, participants had moderate-to-severe depression using the Montgomery-Asberg Depression Rating Scale (MADRS) and Clinical Global Impressions Severity (CGI-S) scales. There was a significant overall reduction in MADRS and CGI-S scores in the treatment group compared with the BUP monotherapy with improvement observed as early as week 1 of treatment. Later, a phase 3 study was conducted comparing DEX-BUP 45 mg/105 mg with placebo in patients with moderate-to-severe MDD. Similarly, MADRS and CGI-S scores were significantly reduced in the treatment group. Adverse effects were similar in all groups.

THERAPEUTIC ADVANCE

Clinical response to first line treatment options for MDD are reported to be 40%-60%. Availability of additional treatment options, particularly those with reduced time to efficacy, may improve overall treatment and patient quality of life. DEX-BUP is a combination option that has been shown to improve depression symptoms as early as 1 week after initiation.

Efficacy, Safety, and Tolerability of Psychedelics in Treatment-Resistant Depression (TRD)

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder, associated with substantial burden and large economical costs. Notwithstanding various conventional antidepressant treatment options, a large portion of depressed people (ca. 30%) fails to respond to first-line treatment, resulting in treatment-resistant depression (TRD). Although non-response to multiple antidepressant interventions is a common outcome, a consensus definition of TRD is not yet available. In practice, TRD is applied when two or more successive treatments with different antidepressants are not working. The last decade's intense research into new medicines for TRD has led to two developments, using typical or serotonergic (psilocybin, ayahuasca) and atypical (glutamatergic) psychedelics (ketamine, esketamine). Both approaches, although via different entrance mechanism, exhibit a fast onset but also long-lasting antidepressant effect far beyond the biological presence of the drug in the body, strongly indicating that downstream mechanisms activated by signaling cascades in the brain are involved. The present chapter describes the clinical development of psilocybin and esketamine for TRD and discusses the problems involved in the use of a proper placebo because of the psychotomimetic (psilocybin) or dissociative (ketamine) effects that interfere with performing "blind" studies. Nevertheless, intranasal esketamine was developed and approved for TRD, whereas psilocybin has shown positive results. Adverse effects and tolerability of both drugs in the dose ranges used are generally acceptable. The emergence of anti-TRD medicines for treatment of a very severe disease is a breakthrough in psychiatry.

[Targeting NMDAR/AMPAR: a promising pharmacotherapeutic approach for depressive disorders]

Depression is a leading cause of disability and reduced work capacity worldwide. The monoamine theory of the pathogenesis of depression has remained dominant for many decades, however, drugs developed on its basis have limited efficacy. Exploring alternative mechanisms underlying this pathology could illuminate new avenues for pharmacological intervention. Targeting glutamatergic pathways in the CNS, particularly through modulation of NMDA and AMPA receptors, demonstrates promising results. This review presents some existing drugs with glutamatergic activity and novel developments based on it to enhance the efficacy of pharmacotherapy for depressive disorders.

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.