Antidepressant efficacy of agomelatine: meta-analysis of published and unpublished studies

Efficacy and safety of agomelatine versus SSRIs/SNRIs for post-stroke depression: a systematic review and meta-analysis of randomized controlled trials

Agomelatine is effective in the treatment of depression, but its effect for post-stroke depression (PSD) remains unclear. This study was conducted to compare the efficacy and safety of agomelatine versus SSRIs/SNRIs in treating PSD. We systematically searched Embase, PubMed, Cochrane Library, WanFang Data, China National Knowledge Infrastructure, and Cqvip databases for double-blind randomized controlled studies comparing the efficacy and safety of agomelatine versus SSRIs/SNRIs for PSD until December 2022. The primary efficacy endpoint was the Hamilton Depression Rating Scale (HAMD) score, and the primary safety endpoint was the incidence of overall adverse reactions. Nine studies comprising 857 patients with PSD were included. After 6-12 weeks of treatment, the HAMD score ( P  = 0.16) and the overall response rates ( P  = 0.20) in the agomelatine group were comparable to that in the SSRIs/SNRIs group. Participants treated with agomelatine achieved higher Barthel Index scores compared with the SSRIs/SNRIs group ( P  = 0.02). There was a significantly lower incidence of overall adverse reactions ( P  = 0.008) and neurological adverse reactions ( P  < 0.0001) in the agomelatine group. The efficacy of agomelatine for treating PSD is probably comparable to that of SSRIs/SNRIs, and it may improve stroke outcomes with better safety.

The Effects of Fluoxetine and Agomelatine on Neurocognitive Functions and Sleep in Patients with Major Depressive Disorder

Background

We aimed to evaluate the effects of 6 weeks of agomelatine versus fluoxetine treatment on cognition and sleep.

Methods

Agomelatine 25 mg/day and fluoxetine 20 mg/day were administered to major depressive disorder (MDD) patients. Assessments were conducted before the treatment and at the sixth week of treatment via psychometric measures and comprehensive neurocognitive assessments of various functions, including executive skills, attention, memory, verbal fluency, and speed of processing.

Results

They both improved the evaluated neurocognitive test scores (P < .05), except for the scores of the Digit Span Test (P > .05), but only fluoxetine significantly improved the scores of the Controlled Oral Word Association Test (P = .018). Only in relation to the subjective sleep quality part of the Pittsburgh Sleep Quality Index (P = .035) and the Trail Making Test-B (TMT-B) (P = .046) was there an important difference between the study groups, and agomelatine showed better effects than fluoxetine in these measures.

Conclusion

Both drugs improved the neurocognitive functioning in the participants. However, the better effect of agomelatine in improving the TMT-B scores suggests that it is a suitable option for MDD patients with noticeable executive disturbances.

Cool the Inflamed Brain: A Novel Anti-inflammatory Strategy for the Treatment of Major Depressive Disorder

BACKGROUND

Abundant evidence suggests that inflammatory cytokines contribute to the symptoms of major depressive disorder (MDD) by altering neurotransmission, neuroplasticity, and neuroendocrine processes. Given the unsatisfactory response and remission of monoaminergic antidepressants, anti-inflammatory therapy is proposed as a feasible way to augment the antidepressant effect. Recently, there have been emerging studies investigating the efficiency and efficacy of anti-inflammatory agents in the treatment of MDD and depressive symptoms comorbid with somatic diseases.

METHODS

In this narrative review, prospective clinical trials focusing on anti-inflammatory treatment for depression have been comprehensively searched and screened. Based on the included studies, we summarize the rationale for the anti-inflammatory therapy of depression and discuss the utilities and confusions regarding the anti-inflammatory strategy for MDD.

RESULTS

This review included over 45 eligible trials. For ease of discussion, we have grouped them into six categories based on their mechanism of action, and added some other anti-inflammatory modalities, including Chinese herbal medicine and non-drug therapy. Pooled results suggest that anti-inflammatory therapy is effective in improving depressive symptoms, whether used as monotherapy or add-on therapy. However, there remain confusions in the application of anti-inflammatory therapy for MDD.

CONCLUSION

Based on current clinical evidence, anti-inflammatory therapy is a promisingly effective treatment for depression. This study proposes a novel strategy for clinical diagnosis, disease classification, personalized treatment, and prognostic prediction of depression. Inflammatory biomarkers are recommended to be assessed at the first admission of MDD patients, and anti-inflammatory therapy are recommended to be included in the clinical practice guidelines for diagnosis and treatment. Those patients with high levels of baseline inflammation (e.g., CRP > 3 mg/L) may benefit from adjunctive anti-inflammatory therapy.

The multimodal effect of circadian interventions in Parkinson's disease: A narrative review

BACKGROUND

The circadian system and its dysfunction in persons with Parkinson's disease (PwP) has a clear impact on both motor and non-motor symptoms. Examples include circadian patterns in motor disability, with worsening of symptoms throughout the day, but also the existence of similar patterns in non-motor symptoms.

OBJECTIVE

In this narrative review, we discuss the role of the circadian system, we address the role of dopamine in this system, and we summarise the evidence that supports the use of circadian system treatments for motor and non-motor symptoms in PwP.

METHODS

A systematic search in PubMed and Web of Science database was performed and the final search was performed in November 2021. We included articles whose primary aim was to investigate the effect of melatonin, melatonin agonists, and light therapy in PwP.

RESULTS

In total 25 articles were retrieved. Of these, 12 were related to bright light therapy and 13 to melatonin or/and melatonin agonists. Most, but not all, studies showed that melatonin and melatonin agonists and light therapy induced improvements in measures of sleep, depression, motor function, and some also cognitive function and other non-motor symptoms. For some of these outcomes, including daytime sleepiness, depressive symptoms, and some motor symptoms, there is level 2 B evidence for the use of circadian treatments in PwP.

CONCLUSIONS

Treatment with bright light therapy, exogenous melatonin and melatonin agonists seems to have not only positive effects on sleep quality and depression but also on motor function in PwP. Drawbacks in earlier work include the relatively small number of participants and the heterogeneity of outcome measures. Further large and well-designed trials are needed to address these shortcomings and to confirm or refute the possible merits of the circadian system as a treatment target in PwP.

Drugs Used in Circadian Sleep-Wake Rhythm Disturbances

This article focuses on melatonin and other melatonin receptor agonists and summarizes their circadian phase shifting and sleep-enhancing properties, along with their associated possible safety concerns. The circadian system and circadian rhythm sleep-wake disorders are described, along with the latest American Academy of Sleep Medicine recommendations for the use of exogenous melatonin in treating them. In addition, the practical aspects of using exogenous melatonin obtainable over the counter in the United States, consideration of the effects of concomitant light exposure, and assessing treatment response are discussed.

Agomelatine rescues lipopolysaccharide-induced neural injury and depression-like behaviors via suppression of the Gαi-2-PKA-ASK1 signaling pathway

BACKGROUND

Agomelatine has been shown to be effective in the treatment of depression, but the molecular mechanisms underlying its antidepressant effects have yet to be elucidated. Identification of these molecular mechanisms would not only offer new insights into the basis for depression but also provide the foundation for the development of novel treatments for this disorder.

METHODS

Intraperitoneal injection of LPS was used to induce depression-like behaviors in rats. The interactions of the 5-HT2C reporter and Gαi-2 were verified by immunoprecipitation or immunofluorescence assay. Inflammatory related proteins, autophagy related proteins and apoptosis markers were verified by immunoblotting or immunofluorescence assay. Finally, electron microscopy analysis was used to observe the synapse and ultrastructural pathology.

RESULTS

Here, we found that the capacity for agomelatine to ameliorate depression and anxiety in a lipopolysaccharide (LPS)-induced rat model of depression was associated with an alleviation of neuroinflammation, abnormal autophagy and neuronal apoptosis as well as the promotion of neurogenesis in the hippocampal dentate gyrus (DG) region of these rats. We also found that the 5-HT2C receptor is coupled with G alphai (2) (Gαi-2) protein within hippocampal neurons and, agomelatine, acting as a 5-HT2C receptor antagonist, can up-regulate activity of the Gαi-2-cAMP-PKA pathway. Such events then suppress activation of the apoptosis signal-regulating kinase 1 (ASK1) pathway, a member of the mitogen-activated protein kinase (MAPK) family involved in pathological processes of many diseases.

CONCLUSION

Taken together, these results suggest that agomelatine plays a neuroprotective role in regulating neuroinflammation, autophagy disorder and apoptosis in this LPS-induced rat model of depression, effects which are associated with the display of antidepressant behaviors. These findings provide evidence for some of the potential mechanisms for the antidepressant effects of agomelatine.

The efficacy of psychotherapies and pharmacotherapies for mental disorders in adults: an umbrella review and meta-analytic evaluation of recent meta-analyses

Mental disorders represent a worldwide public health concern. Psychotherapies and pharmacotherapies are recommended as first line treatments. However, evidence has emerged that their efficacy may be overestimated, due to a variety of shortcomings in clinical trials (e.g., publication bias, weak control conditions such as waiting list). We performed an umbrella review of recent meta-analyses of randomized controlled trials (RCTs) of psychotherapies and pharmacotherapies for the main mental disorders in adults. We selected meta-analyses that formally assessed risk of bias or quality of studies, excluded weak comparators, and used effect sizes for target symptoms as primary outcome. We searched PubMed and PsycINFO and individual records of the Cochrane Library for meta-analyses published between January 2014 and March 2021 comparing psychotherapies or pharmacotherapies with placebo or treatment-as-usual (TAU), or psychotherapies vs. pharmacotherapies head-to-head, or the combination of psychotherapy with pharmacotherapy to either monotherapy. One hundred and two meta-analyses, encompassing 3,782 RCTs and 650,514 patients, were included, covering depressive disorders, anxiety disorders, post-traumatic stress disorder, obsessive-compulsive disorder, somatoform disorders, eating disorders, attention-deficit/hyperactivity disorder, substance use disorders, insomnia, schizophrenia spectrum disorders, and bipolar disorder. Across disorders and treatments, the majority of effect sizes for target symptoms were small. A random effect meta-analytic evaluation of the effect sizes reported by the largest meta-analyses per disorder yielded a standardized mean difference (SMD) of 0.34 (95% CI: 0.26-0.42) for psychotherapies and 0.36 (95% CI: 0.32-0.41) for pharmacotherapies compared with placebo or TAU. The SMD for head-to-head comparisons of psychotherapies vs. pharmacotherapies was 0.11 (95% CI: -0.05 to 0.26). The SMD for the combined treatment compared with either monotherapy was 0.31 (95% CI: 0.19-0.44). Risk of bias was often high. After more than half a century of research, thousands of RCTs and millions of invested funds, the effect sizes of psychotherapies and pharmacotherapies for mental disorders are limited, suggesting a ceiling effect for treatment research as presently conducted. A paradigm shift in research seems to be required to achieve further progress.

Agomelatine: An astounding sui-generis antidepressant?

Major depressive disorder (MDD) is one of the foremost causes of disability and premature death worldwide. Although the available antidepressants are effective and well tolerated, they also have many limitations. Therapeutic advances in developing a new drug's ultimate relation between MDD and chronobiology, which targets the circadian rhythm, have led to a renewed focus on psychiatric disorders. In order to provide a critical analysis about antidepressant properties of agomelatine, a detailed PubMed (Medline), Scopus (Embase), Web of Science (Web of Knowledge), Cochrane Library, Google Scholar, and PsycInfo search was performed using the following keywords: melatonin analog, agomelatine, safety, efficacy, adverse effects, pharmacokinetics, pharmacodynamics, circadian rhythm, sleep disorders, neuroplasticity, MDD, bipolar disorder, anhedonia, anxiety, generalized anxiety disorder (GAD), and mood disorders. Agomelatine is a unique melatonin analog with antidepressant properties and a large therapeutic index that improves clinical safety. It is a melatonin receptor agonist (MT1 and MT2) and a 5-HT2C receptor antagonist. The effects on melatonin receptors enable the resynchronization of irregular circadian rhythms with beneficial effects on sleep architectures. In this way, agomelatine is accredited for its unique mode of action, which helps to exert antidepressant effects and resynchronize the sleep-wake cycle. To sum up, an agomelatine has not only antidepressant properties but also has anxiolytic effects.

Antidepressant efficacy of Agomelatine: Meta-analysis of placebo controlled and active comparator studies

Agomelatine is a novel antidepressant that was developed to counter the adverse effects associated with the standard SSRIs and SNRIs that limited their usage. Publication bias was identified in antidepressant trials which can potentially overestimate the treatment efficacy. This meta-analysis was designed to assess the overall antidepressant effect of Agomelatine by pooling all the published and unpublished studies available till date. Studies conducted on adult patients who met with the criteria for MDD that evaluated efficacy of Agomelatine at acute phase (6-12weeks) and at long term phase (24weeks) were included. The primary efficacy measured with SMD of final mean scores of HAM-D and MADRS. Secondary efficacy measures of Response, remission and safety parameters were evaluated with relative risks. RevMan version 5.4 was used for analysis of both continuous (Standardized mean difference) and dichotomous outcomes (response, remission and all cause of discontinuation). Efficacy parameters were presented with 99% confidence intervals while safety parameters were presented with 95% CI. A total of 9233 patients were included from 27 studies. In acute phase placebo controlled studies, Agomelatine had a statistically significant SMD of - 0.24 (-0.39 to -0.09) and response rate of (1.25, 1.07-1.47). In comparison (RR 0.99, 0.92-1.07) Agomelatine is an effective antidepressant having similar efficacy with the currently used antidepressants.

Effect of regulatory interventions on agomelatine use in Spain: A multiple intervention time-series analysis in a nationwide electronic healthcare record database

BACKGROUND

Liver injury is an important identified risk for agomelatine and several measures were put in place to prevent and minimize such risk. The study aims to assess the impact of four interventions on the incidence of agomelatine use, particularly among patients aged ≥75 in Spain between 2011 and 2018.

METHODS

Quasi-experimental interrupted time-series analysis to examine data from a nationwide electronic healthcare record database (BIFAP). Quarterly cumulative incidence of agomelatine use per 100 000 patients was calculated and the impact of four regulatory interventions was quantified.

RESULTS

The incidence of agomelatine use decreased by 85% and 87% from first quarter 2011 to last quarter 2018 in patients below and above 75 years old, respectively. Regulatory actions taken were not associated with an immediate and significant falling level of use or slope. The incidence was less than expected 6 months after the first and third intervention for patients below and above 75 years old, and more than expected after the second and fourth intervention for both populations, though these analyses were underpowered to observe significant results. The downward trend became less pronounced, reaching a residual level of use, which remained stable in the last segment of the study period.

CONCLUSION

New users of agomelatine decreased throughout the study period, starting before interventions took place. The effect of specific interventions might be masked by the progressive decrease tendency, constant over the study period. The effects of external factors that might overlap, unintended consequences, and issues concerning statistical modeling in situations where rates are already falling, should be considered when interpreting the results.

Agomelatine might be more appropriate for elderly, depressed, type 2 diabetes mellitus patients than paroxetine/fluoxetine

Agomelatine was a novel and melatonergic antidepressant. The present study was conducted to find out whether age was an important factor for agomelatine in treating depressed type 2 diabetes mellitus (T2DM) patients. In total, 193 depressed T2DM patients were included. There were 84 patients ranged from 27 years old to 49 years old (age phase I) (n = 44 receiving agomelatine, n = 40 receiving paroxetine or fluoxetine), and 109 patients ranged from 50 years old to 70 years old (age phase II) (n = 56 receiving agomelatine, n = 53 receiving paroxetine or fluoxetine). The Hamilton Depression Rating Scale (HDRS) score, Hamilton Anxiety Rating Scale (HARS) score, fasting plasma glucose (FPG), hemoglobin A1c (HbA1c) level and body mass index (BMI) were assessed after 12 weeks treatment. After treatment, we found that among patients in age phase I, there were no significant differences in final average HDRS score, HARS score, FPG, HbA1c level, BMI, response rate and remission rate between the two groups. However, among patients in age phase II, compared to patients receiving paroxetine or fluoxetine, patients receiving agomelatine had the significantly lower average HDRS score, HARS score, HbA1c level and BMI, and significantly higher response rate and remission rate. The incidence of treatment-related adverse events was similar between the two groups in both age phases. These results suggested that age was an important factor for agomelatine in treating depressed T2DM patients. Compared to paroxetine/fluoxetine, agomelatine might be more appropriate for elderly depressed T2DM patients.

Gut Hormones as Potential Therapeutic Targets or Biomarkers of Response in Depression: The Case of Motilin

Recent research has identified the gut–brain axis as a key mechanistic pathway and potential therapeutic target in depression. In this paper, the potential role of gut hormones as potential treatments or predictors of response in depression is examined, with specific reference to the peptide hormone motilin. This possibility is explored through two methods: (1) a conceptual review of the possible links between motilin and depression, including evidence from animal and human research as well as clinical trials, based on a literature search of three scientific databases, and (2) an analysis of the relationship between a functional polymorphism (rs2281820) of the motilin (MLN) gene and cross-national variations in the prevalence of depression based on allele frequency data after correction for potential confounders. It was observed that (1) there are several plausible mechanisms, including interactions with diet, monoamine, and neuroendocrine pathways, to suggest that motilin may be relevant to the pathophysiology and treatment of depression, and (2) there was a significant correlation between rs2281820 allele frequencies and the prevalence of depression after correcting for multiple confounding factors. These results suggest that further evaluation of the utility of motilin and related gut peptides as markers of antidepressant response is required and that these molecular pathways represent potential future mechanisms for antidepressant drug development.

Drug use evaluation: A two-year retrospective review of the effectiveness and tolerability of agomelatine versus mirtazapine in patients with depressive disorder

OBJECTIVE

To compare the effectiveness and tolerability of agomelatine with mirtazapine in patients with depressive disorder. To illustrate the prescribing pattern of agomelatine and identify factors that affect the pattern of treatment result and therapeutic outcome of it.

METHODS

The clinical data of patients using agomelatine or mirtazapine, 93 patients in each group, were included and reviewed in this retrospective study. Background characteristics, adverse events, therapeutic outcomes (discontinued or continued), reason of discontinuation, and the presence of positive pattern of treatment result were assessed. Positive pattern of treatment result was defined as either recovery or improvement of depressive disorder after therapy.

RESULTS

Patients using agomelatine were associated with higher starting dose and higher dose titrated than mirtazapine. More patients started agomelatine due to intolerability, and less due to ineffectiveness of the previous antidepressant. More patients started agomelatine before the use of at least two selective serotonin reuptake inhibitor (SSRI)/serotonin-noradrenaline reuptake inhibitor (SNRI). Patients using agomelatine were associated with less discontinuation due to intolerability, and less experience of adverse events within 90 days of initiation or dose increase, but more discontinuation due to ineffectiveness versus mirtazapine. The use of 50 mg resulted in less discontinuation. The use of at least two SSRI(s)/SNRI(s) before and more concomitant medications are independently associated with more discontinuation due to intolerability. The use of at least two SSRI(s)/SNRI(s) before was also associated with more adverse events. Using agomelatine as an augmentation to other antidepressant(s) and at a higher dose were independently associated with the experience of positive pattern of treatment result.

CONCLUSION

Agomelatine was more tolerable than mirtazapine, but could result in more discontinuation due to ineffectiveness. The use of higher dose and as an augmentation to other antidepressant(s) could improve the desired treatment result of agomelatine.

Agomelatine Softens Depressive-Like Behavior through the Regulation of Autophagy and Apoptosis

Depression is a common and disabling mental disorder with high recurrence rate. Searching for more effective treatments for depression is a long-standing primary objective in neuroscience. Agomelatine (AGO) was reported as an antidepressant with unique pharmacological effects. However, its effects and the underlying mechanism are still unclear. In this study, we sought to evaluate the antidepressant effects of AGO on the chronic restraint stress (CRS) mouse model and preliminarily investigate its effects on the gut microbial metabolites. The CRS model mice were established in 28 days with AGO (60 mg/kg/day, by oral) or fluoxetine (15 mg/kg/day, by oral) administration. The number of behavioral tests was conducted to evaluate the effect of AGO on depression-like behavior alleviation. Meanwhile, the expression of the BDNF/TrkB/pERK signaling pathway, apoptosis, autophagy, and inflammatory protein markers were assessed using western blot and immunofluorescence. Our findings show that AGO can attenuate the depressive-like behavior that significantly appeared in both sucrose preference and forced swimming tests. Additionally, a noticeable upregulation of autophagy including Beclin1 and LC3II, microglial activity marker Iba-1, and BDNF/TrkB/pERK signaling pathways are indicated. An obvious decreased expression of NF-κB, iNOS, and nNOS as well as apoptosis including Bax is observed in AGO administration mice. On the other hand, we found that AGO impacted the rebalancing of short-chain fatty acids (SCFAs) in mouse feces. Altogether, these findings suggest that AGO can exert antidepressant effects in a different molecular mechanism.

Circadian depression: A mood disorder phenotype

Major mood syndromes are among the most common and disabling mental disorders. However, a lack of clear delineation of their underlying pathophysiological mechanisms is a major barrier to prevention and optimised treatments. Dysfunction of the 24-h circadian system is a candidate mechanism that has genetic, behavioural, and neurobiological links to mood syndromes. Here, we outline evidence for a new clinical phenotype, which we have called 'circadian depression'. We propose that key clinical characteristics of circadian depression include disrupted 24-h sleep-wake cycles, reduced motor activity, low subjective energy, and weight gain. The illness course includes early age-of-onset, phenomena suggestive of bipolarity (defined by bidirectional associations between objective motor and subjective energy/mood states), poor response to conventional antidepressant medications, and concurrent cardiometabolic and inflammatory disturbances. Identifying this phenotype could be clinically valuable, as circadian-targeted strategies show promise for reducing depressive symptoms and stabilising illness course. Further investigation of underlying circadian disturbances in mood syndromes is needed to evaluate the clinical utility of this phenotype and guide the optimal use of circadian-targeted interventions.

New agents and perspectives in the pharmacological treatment of major depressive disorder

Despite the important advances in the understanding of the pathophysiology of MDD, a large proportion of depressed patients do not respond well to currently available pharmacological agents. The present review focuses on new targets and future directions in the pharmacological treatment of MDD. Novel agents and their efficacy in the treatment of depression are discussed, with a focus on the respectively target pathophysiological pathways and the level of available evidence. Although it is expected that classic antidepressants will remain the cornerstone of MDD treatment, at least for the near future, a large number of novel compounds is currently under investigation as for their efficacy in the treatment of MDD, many of which with promising results.

Efficacy of Agomelatine 25-50 mg for the Treatment of Anxious Symptoms and Functional Impairment in Generalized Anxiety Disorder: A Meta-Analysis of Three Placebo-Controlled Studies

Introduction

The purpose of this study is to investigate the effects of agomelatine on anxious symptoms and functional impairment in a pooled dataset from randomized placebo-controlled trials for generalized anxiety disorder (GAD).

Methods

Data from three randomized, placebo-controlled trials that evaluated the efficacy of agomelatine 25–50 mg were pooled. The short-term (12 weeks) efficacy of agomelatine was assessed in regards to (1) anxious symptoms using the Hamilton Anxiety Scale (HAM-A), and (2) functional impairment using the Sheehan Disability Scale (SDS). Meta-analysis using a random effect model was used to assess differences between groups. Remission and response rates for the HAM-A and SDS were calculated, and analyses were repeated in participants with more severe anxiety symptoms.

Results

In total, 669 patients (340 on agomelatine; 329 on placebo) were included in the analyses. Compared to placebo, the agomelatine group had a significant reduction in HAM-A total score at week 12 (between group difference: 6.30 ± 2.51, p = 0.012). Significant effects were also found for symptom response on the HAM-A (67.1% of patients on agomelatine vs. 32.5% on placebo) and symptom remission (38.8% of patients on agomelatine vs. 17.3% on placebo). Compared to placebo, there was a significant difference in favour of the agomelatine group at week 12 on the SDS total score (5.11 ± 1.81, p = 0.005). Significant effects were also found for functional response on the SDS (79.1% of patients on agomelatine vs. 43.2% of placebo) and functional remission (55.2% of patients on agomelatine vs. 25.4% on placebo). All findings for anxious symptoms and functional impairment were confirmed in the subset of more severely anxious patients. Agomelatine was well tolerated by patients.

Conclusion

This meta-analysis confirms that agomelatine reduces anxiety symptoms and improves the global functioning of GAD patients.

Supplementary Information

The online version of this article (10.1007/s12325-020-01583-9) contains supplementary material, which is available to authorized users.

Agomelatine, A Potential Multi-Target Treatment Alternative for Insomnia, Depression, and Osteoporosis in Postmenopausal Women: A Hypothetical Model

Insomnia, which is associated with menopausal depression, is a common symptom of menopause. Both symptoms have a common etiology, and can affect each other significantly. Pharmacological interventions, including hypnotics and antidepressants, and non-pharmacological therapies are generally administered in clinical practice for insomnia treatment. As another menopausal disorder, osteoporosis is described as a disease of low bone mineral density (BMD), affecting nearly 200 million women worldwide. Postmenopausal osteoporosis is common among middle-aged women. Since postmenopausal osteoporosis mainly results from low estrogen levels, menopausal hormone therapy (HT) is considered the first-line option for the prevention of osteoporosis during the menopausal period. However, almost no study has evaluated novel treatments for the combined prevention of insomnia, depression, and osteoporosis. Hence, it is necessary to develop new multi-target strategies for the treatment of these disorders to improve the quality of life during this vulnerable period. Melatonin is the major regulator of sleep, and it has been suggested to be safe and effective for bone loss therapy by MT-2 receptor activity. As a result, we hypothesize that agomelatine, an MT-1 and MT-2 receptor agonist and 5-HT_2C receptor antagonist, holds promise in the combined treatment of insomnia, depression, and osteoporosis in middle-aged women during menopause.

The safety of agomelatine in standard medical practice in depressed patients: A 26-week international multicentre cohort study

OBJECTIVE

The present observational cohort study documented the safety of agomelatine in current medical practice in out-patients suffering from major depressive disorder.

METHOD

The 6-month evolution of agomelatine-treated patients was assessed with a focus on safety (emergent adverse events, liver acceptability), severity of depression using the Clinical Global Impression Severity (CGI-S) score, and functioning measured by the Sheehan Disability Scale (SDS).

RESULTS

A total of 8453 depressed patients from 761 centres in 6 countries were analysed (female: 67.7%; mean age: 49.1 ± 14.8 years). Adverse events reported were in accordance with the known safety profile of agomelatine. Cutaneous events were reported in 1.7% of the patients and increased hepatic transaminases values were reported in 0.9 % of the patients. The incidence of events related to suicide/self-injury was 1.0%. Two completed suicides, not related to the study drug, were reported. CGI-S total scores and SDS sub-scores improved and numbers of days lost or underproductive decreased over the treatment period.

CONCLUSIONS

In standard medical practice, agomelatine treatment was associated with a low incidence of side effects. No unexpected events were reported. A decrease in the severity of the depressive episode and improved functioning were observed.

TRIAL REGISTRATION NAME

Observational cohort study to evaluate the safety of agomelatine in standard medical practice in depressed patients. A prospective, observational (non-interventional), international, multicentre cohort study.

TRIAL REGISTRATION NUMBER

ISRCTN53570733.

Agomelatine in Standard Medical Practice in Depressed Patients: Results of a 1-Year Multicentre Observational Study In France

Background and Objectives

Non-interventional studies are a valuable source of evidence that is complementary to traditional randomised, blinded and controlled clinical trials, for evaluating antidepressants in a real-world setting. The aim of the present study was to document the use of agomelatine in current medical practice and evaluate its effectiveness and safety in outpatients prescribed agomelatine to treat their current depressive episode.

Methods

This 12-month observational French study included patients initiating agomelatine treatment. The intensity and severity of depression were assessed using the 17-item Hamilton Depression Rating Scale (HAM-D17) total score and the Clinical Global Impression-Severity of Illness (CGI-S) scale. Patients’ quality of life and functioning were measured using the Quality of Life in Depression Scale and the Sheehan Disability Scale, respectively. The safety measures included emergent adverse events and biological samplings, with a focus on liver acceptability.

Results

A total of 1484 patients (70% of women; 49.6 ± 15.4 years of age) were enrolled in the study. Most patients (62.3%) were treated with agomelatine for at least 6 months and 28.8% were treated for at least 1 year. Mean HAM-D17 total score and mean CGI-S scores decreased by 13.6 ± 8.1 and 2.1 ± 1.5 points, respectively, from baseline to last visit on agomelatine. Rates of responders (i.e. with a decrease in HAM-D17 total score by at least 50%) and remitters (HAM-D total score < 7) at the last visit were 90.7% and 56.0%, respectively. The mean HAM-D total score decreased after agomelatine withdrawal (− 4.1 ± 6.7) until the last visit. The quality of life and daily functioning of patients improved, while the numbers of days lost and underproductive days decreased over the follow-up period. Safety findings were in accordance with the known information regarding agomelatine.

Conclusion

In the current medical practice, this study confirms the effectiveness and good tolerability of agomelatine administered for a treatment period in agreement with guideline recommendations.

Trial registration number

ISRCTN53570733 on 27 August 2010.

Drugs Used in Circadian Sleep-Wake Rhythm Disturbances

This article focuses on melatonin and other melatonin receptor agonists, and specifically their circadian phase shifting and sleep-enhancing properties. The circadian system and circadian rhythm sleep-wake disorders are briefly reviewed, followed by a summary of the circadian phase shifting, sleep-enhancing properties, and possible safety concerns associated with melatonin and other melatonin receptor agonists. The recommended use of melatonin, including dose and timing, in the latest American Academy of Sleep Medicine Clinical Practice Guidelines for the treatment of intrinsic circadian rhythm disorders is also reviewed. Lastly, the practical aspects of treatment and consideration of clinical treatment outcomes are discussed.

Agomelatine for the Treatment of Generalized Anxiety Disorder: A Meta-Analysis

Objective

Despite multiple drugs available, a large proportion of patients with generalized anxiety disorder (GAD) do not show adequate response and remission. Thus, additional novel pharmacological agents are needed to increase treatment option for GAD. We aimed to investigate efficacy and safety of agomelatine in the treatment of GAD by conducting a meta-analysis.

Methods

An extensive search of multiple databases and clinical trial registries were conducted. Mean change in total scores on Hamilton Anxiety Rating Scale (HAM-A) from baseline to endpoint was our primary outcome measure. Secondary efficacy measures included response and remission rates, as defined by a 50% or greater reduction in HAM-A total scores and a score of 7 or less in HAM-A total scores at study endpoint respectively.

Results

Four published double blinded, randomized, placebo-controlled trials were included in this meta-analysis. Agomelatine more significantly (standardized mean difference = −0.56, p = 0.004) improved HAM-A total scores than placebo. The odds ratios (ORs) of agomelatine over placebo for response and remission rates were 3.75 (p < 0.00001) and 2.74 (p < 0.00001), respectively. Agomelatine was generally well tolerated with insignificance in dropout rate, somnolence, headache, nasopharyngitis, and dizziness compared with placebo. However, agomelatine showed significantly higher incidence of liver function increment (OR = 3.13, p = 0.01) and nausea (OR = 3.27, p = 0.02).

Conclusion

We showed that agomelatine may be another treatment option in patients with GAD. However, the results should be interpreted and translated into clinical practice with caution because the meta-analysis was based on limited numbers of clinical trials.

The preclinical discovery and development of agomelatine for the treatment of depression

INTRODUCTION

Under the treatment of commonly used antidepressants, many patients with major depressive disorder (MDD) do not achieve remission. All previous first-line treatments for depression have focused on the enhancement of monoaminergic activity. Agomelatine was the first antidepressant with a mechanism of action extending beyond monoaminergic neurotransmission.

AREAS COVERED

The aim of this case history is to describe the discovery strategy and development of agomelatine. The pharmacodynamic profile of the drug is briefly presented. The article summarizes (a) the preclinical behavioral data on agomelatine's effects on depressive-like behavior, anxiety, and circadian rhythmicity disruptions, and (b) the results of early preclinical studies on safety, efficacy in MDD, and the risk-benefit pharmacological profile. Furthermore, the article examines findings of post-marketing research on safety, efficacy, and cost-effectiveness of the drug.

EXPERT OPINION

There is now evidence supporting the clinical efficacy and safety profile of agomelatine in the acute-phase treatment of MDD. Agomelatine may be more effective in specific subgroups of MDD patients, those with severe anxiety symptoms or disturbed circadian profiles. Its antidepressant and anxiolytic activities are due to synergy between its melatonergic and 5-hydroxytryptaminergic effects. Since its discovery, novel compounds acting on the melatonergic system have been under investigation for the treatment of MDD.

Comparative efficacy and tolerability of pharmacological treatments for the treatment of acute bipolar depression: A systematic review and network meta-analysis

OBJECTIVE

We investigated the comparative efficacy and tolerability of pharmacological treatment strategies for the treatment of acute bipolar depression.

DATA SOURCES

A systematic review and network meta-analysis was conducted by searching eight registries for published and unpublished, double-blind, randomized controlled trials of pharmacotherapies for the acute treatment of bipolar depression.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines were used for abstracting data, while the Cochrane Risk of Bias Tool was used to assess data quality. Data extraction was done independently by two reviewers, with discrepancies resolved by consensus. Data were pooled using a random-effects model.

MAIN OUTCOMES AND MEASURES

Primary outcomes were efficacy (response and remission rate) and acceptability (completion of treatment and dropouts due to adverse events). Summary odds ratios (ORs) were estimated using pairwise and network meta-analysis with random effects.

RESULTS

Identified citations (4,404) included 50 trials comprising 11,448 participants. Escitalopram, phenelzine, moclobemide, carbamazepine, sertraline, lithium, paroxetine, aripiprazole, gabapentin and ziprasidone appear to be ineffective as compared to placebo in treatment of bipolar depression. Divalproex, olanzapine/fluoxetine, olanzapine, quetiapine, cariprazine, and lamotrigine, appear to be effective as compared to placebo in treatment of bipolar depression according to the network meta-analysis. Aripiprazole showed higher discontinuation rates versus placebo due to the appearance of any adverse event. Quetiapine was better than placebo at reducing treatment-emergent affective switches. For Bipolar I Disorder, cariprazine, fluoxetine, imipramine, lamotrigine, lurasidone, olanzapine-fluoxetine, and olanzapine were significantly better than placebo at response, while fluoxetine, imipramine, cariprazine, lurasidone, olanzapine-fluoxetine, and olanzapine were significantly better than placebo at remission.

CONCLUSIONS AND RELEVANCE

These results could serve evidence-based practice and inform patients, physicians, guideline developers, and policymakers on the relative benefits of the different antidepressants, antipsychotics, and mood-stabilizing agents for the treatment of bipolar depression.

REGISTRATION

PROSPERO (CRD42019122172).

Role of biological rhythm dysfunction in the development and management of bipolar disorders: a review

Disturbance of biological rhythms contributes to the onset of bipolar disorders and is an important clinical feature of the condition. To further explore the role of biological rhythms in bipolar disorders, 95 English articles published between 1968 and 2019 were retrieved from the PubMed database and analysed. We herein review the outcomes of studies on biological rhythm disturbance in bipolar disorders, including the epidemiology, aetiology, clinical features (eg, sleep, feeding and eating disorders) and treatment of the condition evaluated by patients’ self-report and biological indicators such as melatonin. Our report supports the characterisation of biological rhythm disturbance as a significant clinical feature affecting the onset and development of bipolar disorders and reviews classical and novel treatments, such as chronotherapy, that can be applied in the clinical practice. Our analysis indicates that a more comprehensive study of the pathophysiology, clinical phenomenology and treatment of biological rhythm disturbance is required.

Publication bias in diagnostic imaging: conference abstracts with positive conclusions are more likely to be published

OBJECTIVE

To evaluate whether imaging diagnostic test accuracy conference abstracts with positive conclusions or titles are more likely to reach full-text publication than those with negative (or neutral) conclusions or titles.

METHODS

Diagnostic accuracy research abstracts were included if they were presented at the 2011 or 2012 Radiological Society of North America conference. Full-text publication status at 5 years post conference abstract submission was determined. Conclusion and title positivity of conference abstracts were extracted, as well as potential confounding factors. The associations of conclusion and title positivity with publication status at 5 years post conference abstract submission were assessed using a multivariable logistic regression model. Conditional odds ratios were calculated to express the strength of associations, adjusting for the confounders.

RESULTS

In total, 282/400 (71%) of included conference abstracts reached full-text publication. A total of 246 out of 337 (74%) conference abstracts with positive conclusions resulted in full-text publications, compared with 26/48 (54%) with neutral conclusions and 5/15 (33%) with negative conclusions. In multivariable logistic regression, conclusion positivity was significantly associated with full-text publication (odds ratio 3.6; 95% CI 1.9-6.7 for conference abstracts with positive conclusions, compared with those with non-positive conclusions); this did not apply to title positivity (odds ratio 1.2; 95% CI 0.47-3.0).

CONCLUSION

Imaging conference abstracts with positive conclusions were more likely to be published as full-text articles. Title positivity was not associated with publication. This preferential publication pattern may lead to an overrepresentation of positive studies in the literature. An overrepresentation of positive studies may contribute to inflated estimates of test accuracy and has the potential to adversely influence patient care.

KEY POINTS

• Imaging diagnostic test accuracy conference abstracts with positive conclusions were more likely to be reported as full-text articles than those with non-positive conclusions. • The majority (75%) of imaging diagnostic test accuracy conference abstracts with positive conclusions were published, compared with only 53% and 33% with neutral and negative conclusions, respectively. • Conclusion positivity remained associated with the full-text publication of conference abstracts when controlling for multiple potential confounding variables.

Application of Item Response Theory to Model Disease Progression and Agomelatine Effect in Patients with Major Depressive Disorder

INTRODUCTION

In this paper, we studied the effect over time of agomelatine, an antidepressant drug administered in patient with major depressive disorder, through item response theory (IRT), taking into account a strong placebo effect and missing not at random. We also assessed the informativeness of the HAMD-17 scale's item.

MATERIALS AND METHODS

The data includes five phase III clinical trials sponsored by Servier Institute, totalling 1549 patients followed during a maximum of 1 year. At each observation, individual scores for the 17 items of the HAMD scale were recorded. The probability for each score was modelled with IRT. A non-linear mixed effects model was used to describe the evolution of the disease and was coupled with a time to event model to predict dropout. Clinical trial simulations were then used to compare placebo and active treatment. Informativeness of each item was evaluated using the Fisher information theory.

RESULTS

The best model combined an IRT model, a longitudinal model for underlying depression which describes the remission and then a possible relapse, and a hazard model for dropout depending on the evolution from baseline. The drug effect was best modelled as an effect on the remission and the relapse phases. The median predicted drop in HAMD between baseline and 6 weeks was 8.8 (90% PI, 8.3-9.2) when on placebo and 13.1 (90% PI, 12.8-13.4) when treated. Nine items were found to be the most informative.

CONCLUSION

The IRT framework allowed to characterise the evolution of depression with time and estimate the effect of agomelatine, as well as the link between symptoms and disease.

A model of human endogenous retrovirus (HERV) activation in mental health and illness

Despite strong evidence for the heritability of major depressive disorder (MDD), efforts to identify causal genes have been disappointing. Furthermore, although there is strong support for life stress as a major predictor of MDD, there are also considerable individual differences in susceptibility and resilience that remain poorly understood. Efforts to identify specific gene-by-environment risk factors produced results that were initially encouraging, but that were not supported by later large-scale studies. Here I propose a novel mechanism that could address the "missing heritability" of MDD, the role of environmental risk factors, and individual differences in susceptibility and resilience. This mechanism focuses on a class of transposable elements, Human Endogenous Retroviruses (HERVs), which make up approximately 8% of the human genome as the result of ancient retroviral infections that entered mammalian germ lines throughout the course of evolution. My primary hypothesis is that exposure to either exogenous viruses or traumatic experiences can activate HERVs in the brain to cause depressive (and possibly other psychiatric) symptoms. My secondary hypothesis is that individual differences in vulnerability or resilience result from the balance of activated HERVs with pathogenic versus protective functions in the brain. Future research can test these hypotheses by analysis of postmortem human brain tissue from donors with known viral or trauma histories; animal studies manipulating HERV expression; cell culture studies examining regulatory mechanisms of HERV expression; and from brain imaging studies of individuals with known HERV-expression. Such research may reveal novel functions of HERVs in neural tissue and may lead to a new generation of psychiatric interventions designed to target aberrant HERV activation.

Reactive Depression: Lost in Translation!

The old classification of depression as reactive and endogenous, which are still observed in clinical practice, both cannot be accommodated under the current rubric of major depression. This is because psychiatric nosology under the Diagnostic and Statistical Manual of Mental Disorders (DSM) and its latest fifth edition (DSM-V) is still descriptive and not etiologic. The aim of this review was to revisit reactive and endogenous categories of depression from the perspective of today's understanding of etiological pathways. From an epigenetic perspective, the old dichotomy of reactive versus endogenous is interrelated through the impact of the environment (e.g., stress). This includes familial or prenatal depression, where the environmental impact is before birth, or childhood depression, where the early life stress is the precipitating factor to genetic susceptibility. In conclusion, searching for both environmental impact (e.g., stressors) and genetic predispositions in depression, even at a clinical level, could help clinicians with better therapeutic decisions.

Dopaminergic impact of cART and anti-depressants on HIV neuropathogenesis in older adults

The success of combination antiretroviral therapy (cART) has transformed HIV infection into a chronic condition, resulting in an increase in the number of older, cART-treated adults living with HIV. This has increased the incidence of age-related, non-AIDS comorbidities in this population. One of the most common comorbidities is depression, which is also associated with cognitive impairment and a number of neuropathologies. In older people living with HIV, treating these overlapping disorders is complex, often creating pill burden or adverse drug-drug interactions that can exacerbate these neurologic disorders. Depression, NeuroHIV and many of the neuropsychiatric therapeutics used to treat them impact the dopaminergic system, suggesting that dopaminergic dysfunction may be a common factor in the development of these disorders. Further, changes in dopamine can influence the development of inflammation and the regulation of immune function, which are also implicated in the progression of NeuroHIV and depression. Little is known about the optimal clinical management of drug-drug interactions between cART drugs and antidepressants, particularly in regard to dopamine in older people living with HIV. This review will discuss those interactions, first examining the etiology of NeuroHIV and depression in older adults, then discussing the interrelated effects of dopamine and inflammation on these disorders, and finally reviewing the activity and interactions of cART drugs and antidepressants on each of these factors. Developing better strategies to manage these comorbidities is critical to the health of the aging, HIV-infected population, as the older population may be particularly vulnerable to drug-drug interactions affecting dopamine.

Effect of Melatonin and Its Analogs on Tear Secretion

Melatonin has been shown to enhance tear secretion associated with dinucleotide diadenosine tetraphosphate. This study investigated the isolated action of melatonin and its analogs, agomelatine, N-butanoyl-2-(2-methoxy-6H-isoindolo[2,1-a]indol-11-yl) ethanamine (IIK7), and 5-methoxycarbonylamino-N-cetyltryptamine (5-MCA-NAT) (10 µl at 100 µM), on tear secretion when applied topically in the rabbit cornea and its relationship with the melatonin MT1, MT2, and MT3/quinone reductase QR2 receptors. The results showed a significant increase in tear secretion, with a maximal effect at 60 minutes for the agonists (138.9% ± 6.5%, 128.9% ± 6.4%, and 120.0% ± 5.2%, respectively; P < 0.05; 100% control) but not for melatonin (101.6% ± 7.9%; P > 0.05). Agonist action was tested combined with the antagonists DH97 (MT2 selective), prazosin (MT3/QR2 inhibitor), and luzindole (nonselective MT membrane receptor) (10 µl at 100 µM). DH97 reversed the effect of agomelatine, IIK7, and 5-MCA-NAT up to 30.85% ± 7.6%,108% ± 7.2%, and 87.01% ± 7.6%, respectively (P < 0.05; 100% control). Luzindole antagonized agomelatine and 5-MCA-NAT up to 67.35% ± 7.6% and 92.12% ± 8%, respectively (P < 0.05). Prazosin only reversed 5-MCA-NAT action up to 84.2% ± 7.7% (P < 0.05). These results suggest different pathways for the agonists to act through MT membrane receptors. Therefore, agomelatine, IIK7, and 5-MCA-NAT act through MT membrane receptors as secretagogues of tear secretion, and these analogs could be considered excellent therapeutic candidates for dry eye treatment. SIGNIFICANCE STATEMENT: Currently, dry eye with aqueous deficit is treated by adding artificial tears palliatively. This study shows that topical installation of three melatonin analogs (agomelatine, IIK7, and 5-MCA-NAT), but not melatonin, in therapeutic doses in the rabbit cornea significantly increases tear production, acting through different melatonin membrane receptor subtypes. Therefore, this study suggests that melatoninergic compounds could be considered excellent therapeutic candidates for dry eye treatment and ocular surface diseases occurring with a reduction in tear production.

Agomelatine for depression: expanding the horizons?

INTRODUCTION

Agomelatine is an antidepressant with unique pharmacological actions; it is both a melatonin agonist and selective serotonin antagonist. Both actions combined are necessary for antidepressant efficacy. Effects on melatonin receptors enable resynchronisation of disrupted circadian rhythms with beneficial effects on sleep patterns. Areas covered: The issue of use of an antidepressant for depression co-morbid with somatic disorders is covered by the authors. A review of the literature from 2000 to August 2018 was undertaken using Scopus and Web of Science with the key words: agomelatine, depression, medical illness. Depression in Parkinson's disease, cardiovascular illness and type II diabetes is reviewed with evidence of efficacy. Bipolar depression and seasonal affective disorder may also react favourably. Agomelatine may have specific efficacy on symptoms of anhedonia. Expert opinion: Despite approval in some major jurisdictions, the drug has failed to gain registration in the United States. A defining issue may be questions about longer term efficacy: unequivocal effectiveness in placebo-controlled relapse prevention studies has not always been demonstrated. Continuation studies suggest maintenance of clinical responsiveness. A major disadvantage of the drug is its' potential hepatotoxicity and the need for repeated clinical laboratory tests.

What combinations of agomelatine with other antidepressants could be successful during the treatment of major depressive disorder or anxiety disorders in clinical practice?

Even with many antidepressant and anxiolytic drugs available on the market, there are still patients who do not respond well to the standard first or second line treatments for affective or anxiety disorders. The antidepressant agomelatine has been used in Europe for several years. Agomelatine, an agonist at melatonin receptors and an antagonist at serotonin receptors, can be particularly useful in patients suffering from a major depressive disorder associated with insomnia. Some clinical data have shown a limited effect for agomelatine in a subset of patients with major depression. A number of case reports published in 2011-2016 describe the effect of agomelatine in combination with an established antidepressant, such as escitalopram, venlafaxine, duloxetine, moclobemide or bupropion. A successful combination of agomelatine was reported after adjunctive use of agomelatine combined with clomipramine, escitalopram, and venlafaxine in patients with major depression or obsessive-compulsive disorder. Moreover, bupropion or moclobemide augmentation with agomelatine in patients with major depressive disorder led to a significant improvement. Other supportive data have been published, such as analysis of the VIVALDI study, although it should be noted that the study was supported by the manufacturer of agomelatine. In this study, agomelatine in combination with other antidepressants was shown to be effective and well tolerated in practice, although the most effective antidepressant treatment in the study consisted of agomelatine alone and not in combination with other antidepressants. There have also been two published case reports about the concomitant use of duloxetine and agomelatine which were not efficacious. The positive results of agomelatine augmentation with other antidepressants should be confirmed through randomized, double-blind clinical trials.

Clocks in the clinic: circadian rhythms in health and disease

Circadian rhythms are endogenously generated recurring patterns of around 24 hours with well-established roles in physiology and behaviour. These circadian clocks are important in both the aetiology and treatment of various psychiatric and metabolic diseases. To maintain physiological homeostasis and optimal functioning, living life synchronised to these clocks is desirable; modern society, however, promotes a '24/7' lifestyle where activity often occurs during the body's 'biological night', resulting in mistimed sleep and circadian misalignment. This circadian desynchrony can increase the risk of disease and can also influence treatment response. Clinicians should be aware of the influence that circadian desynchrony can have on health and disease, in order to potentially develop new therapeutic strategies and to incorporate chronotherapeutics into current treatment strategies to enhance their utility.

Animal models of addiction

In recent years, animal models in psychiatric research have been criticized for their limited translational value to the clinical situation. Failures in clinical trials have thus often been attributed to the lack of predictive power of preclinical animal models. Here, I argue that animal models of voluntary drug intake—under nonoperant and operant conditions—and addiction models based on the Diagnostic and Statistical Manual of Mental Disorders are crucial and informative tools for the identification of pathological mechanisms, target identification, and drug development. These models provide excellent face validity, and it is assumed that the neurochemical and neuroanatomical substrates involved in drug-intake behavior are similar in laboratory rodents and humans. Consequently, animal models of drug consumption and addiction provide predictive validity. This predictive power is best illustrated in alcohol research, in which three approved medications—acamprosate, naltrexone, and nalmefene—were developed by means of animal models and then successfully translated into the clinical situation.

Drugs Used in Circadian Sleep-Wake Rhythm Disturbances

This article focuses on melatonin and other melatonin receptor agonists, and specifically their circadian phase shifting and sleep-enhancing properties. The circadian system and circadian rhythm sleep-wake disorders are briefly reviewed, followed by a summary of the circadian phase shifting, sleep-enhancing properties, and possible safety concerns associated with melatonin and other melatonin receptor agonists. The recommended use of melatonin, including dose and timing, in the latest American Academy of Sleep Medicine Clinical Practice Guidelines for the treatment of intrinsic circadian rhythm disorders is also reviewed. Lastly, the practical aspects of treatment and consideration of clinical treatment outcomes are discussed.

Efficacy and Safety of Agomelatine vs Paroxetine Hydrochloride in Chinese Han Patients with Major Depressive Disorder: A Multicentre, Double-Blind, Noninferiority, Randomized Controlled Trial

PURPOSE

The purpose of this study is to investigate the efficacy, safety, and tolerability of agomelatine and paroxetine in Chinese Han patients with major depressive disorder (MDD).

METHODS

A 8-week, double-blind, randomized, parallel study was conducted in 14 medical centers in mainland China from December 2011 to September 2012. A total of 264 subjects with a primary Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of MDD were randomly assigned to receive agomelatine 25-50 mg/d (n = 132) or paroxetine 20-40 mg/d (n = 132). The primary efficacy was evaluated by the decrease of Hamilton Depression Rating Scale (HAM-D17) scores. The secondary measurements of efficacy included Hamilton Anxiety Rating Scale, Montgomery-Asberg Depression Rating Scale, Sheehan Disability Scale, Clinical Global Impressions-Severity, and Clinical Global Impressions-Improvement. The laboratory test abnormity, and observed and self-reported adverse events were all assessed as the measurements of safety and tolerability.

RESULTS

Both the agomelatine and paroxetine groups showed significant improvement from baseline to the end point (P < 0.05) without between-group differences (P > 0.05). The mean decrease of HAM-D17 of agomelatine group was not inferior to the paroxetine group over the 8-week treatment (agomelatine 15.26 ± 6.44 vs paroxetine 14.87 ± 5.89, δ = 2.0; μA-μB 95% confidence interval, -1.13 to 1.91). The percentage of responders at the last postbaseline assessment was similar in the 2 groups on both HAM-D17 (agomelatine 66.15% vs paroxetine 63.49%) and Clinical Global Impressions-Improvement (agomelatine 79.09% vs paroxetine 80.36%). The anxiety (Hamilton Anxiety Rating Scale) and sleep symptoms (sleep items of HAM-D17) of the patients were improved significantly in the 2 groups at week 8 without between-group differences (P > 0.05). The incidence of overall adverse events was similar in the 2 groups (agomelatine 49.62% vs paroxetine 56.15%, P > 0.05). The incidence of adverse events in skin and subcutaneous tissue was higher in the paroxetine group than in the agomelatine group (none in agomelatine and 4.62% in paroxetine, P = 0.0144).

CONCLUSIONS

Agomelatine showed equivalent antidepressant efficacy to paroxetine in treating MDD patients after 8 weeks of treatment with an acceptable safety.

Mitochondrial Agents for Bipolar Disorder

Background

Bipolar disorder is a chronic and often debilitating illness. Current treatment options (both pharmaco- and psychotherapy) have shown efficacy, but for many leave a shortfall in recovery. Advances in the understanding of the pathophysiology of bipolar disorder suggest that interventions that target mitochondrial dysfunction may provide a therapeutic benefit.

Methods

This review explores the current and growing theoretical rationale as well as existing preclinical and clinical data for those therapies aiming to target the mitochondrion in bipolar disorder. A Clinicaltrials.gov and ANZCTR search was conducted for complete and ongoing trials on mitochondrial agents used in psychiatric disorders. A PubMed search was also conducted for literature published between January 1981 and July 2017. Systematic reviews, randomized controlled trials, observational studies, case series, and animal studies with an emphasis on agents affecting mitochondrial function and its role in bipolar disorder were included. The search was augmented by manually searching the references of key papers and related literature. The results were presented as a narrative review.

Results

Mitochondrial agents offer new horizons in mood disorder treatment. While some negative effects have been reported, most compounds are overall well tolerated and have generally benign side-effect profiles.

Conclusions

The study of neuroinflammation, neurodegeneration, and mitochondrial function has contributed the understanding of bipolar disorder's pathophysiology. Agents targeting these pathways could be a potential therapeutic strategy. Future directions include identification of novel candidate mitochondrial modulators as well as rigorous and well-powered clinical trials.

Defending psychiatry or defending the trivial effects of therapeutic interventions? A citation content analysis of an influential paper

AIMS

Leucht et al. in 2012 described an overview of meta-analyses of the efficacy of medication in psychiatry and general medicine, concluding that psychiatric drugs were not less efficacious than other drugs. Our goal was to explore the dissemination of this highly cited paper, which combined a thought provoking message with a series of caveats.

METHODS

We conducted a prospectively registered citation content analysis. All papers published before June 1st citing the target paper were independently rated by two investigators. The primary outcome coded dichotomously was whether the citation was used to justify a small or modest effect observed for a given treatment. Secondary outcomes regarded mentioning any caveats when citing the target paper, the point the citation was making (treatment effectiveness in psychiatry closely resembles that in general medicine, others), the type of condition (psychiatric, medical or both), specific disease, treatment category and specific type. We also extracted information about the type of citing paper, financial conflict of interest (COI) declared and any industry support. The primary analysis was descriptive by tabulating the extracted variables, with numbers and percentages where appropriate. Co-authorship networks were constructed to identify possible clusters of citing authors. An exploratory univariate logistic regression was used to explore the relationship between each of a subset of pre-specified secondary outcomes and the primary outcome.

RESULTS

We identified 135 records and retrieved and analysed 120. Sixty-three (53%) quoted Leucht et al.'s paper to justify a small or modest effect observed for a given therapy, and 113 (94%) did not mention any caveats. Seventy-two (60%) used the citation to claim that treatment effectiveness in psychiatry closely resembles that in general medicine; 110 (91%) paper were about psychiatric conditions. Forty-one (34%) papers quoted it without pointing towards any specific treatment category, 28 (23%) were about antidepressants, 18 (15%) about antipsychotics. Forty (33%) of the citing papers included data. COIs were reported in 55 papers (46%). Univariate and multivariate regressions showed an association between a quote justifying small or modest effects and the point that treatment effectiveness in psychiatry closely resembles that in general medicine.

CONCLUSIONS

Our evaluation revealed an overwhelmingly uncritical reception and seemed to indicate that beyond defending psychiatry as a discipline, the paper by Leucht et al. served to lend support and credibility to a therapeutic myth: trivial effects of mental health interventions, most often drugs, are to be expected and therefore accepted.Protocol registration: https://osf.io/9dqat/.

Disturbances of diurnal phase markers, behavior, and clock genes in a rat model of depression; modulatory effects of agomelatine treatment

Major depressive disorder (MDD) is a growing problem worldwide. Though, the etiology remains unresolved, circadian rhythm disturbances are frequently observed in MDD and thus is speculated to play a key role herein. The present study focuses on circadian rhythm disturbances in the chronic mild stress (CMS) animal model of depression and examined whether the atypical antidepressant, agomelatine, which is mediating its action via melatonergic and serotonergic receptors, is capable of resynchronizing the perturbed rhythm. Melatonin is often used as a marker of the circadian phase, but the functional and behavioral output is dictated on a cellular level by the molecular clock, driven by the clock genes. We applied in situ hybridization histochemistry to measure the expression levels of the core clock genes, period (Per) 1 and 2 and bone and muscle ARNT-like protein 1 (Bmal1), in multiple brain regions believed to be implicated in depression. Agomelatine showed an antidepressant-like effect in the sucrose consumption test and an anxiolytic-like profile in the elevated zero maze. We found that CMS increased nighttime melatonin release in rats and that agomelatine attenuated this effect. Stress was shown to have a time and region-specific effect on clock gene expression in the brain. Treatment with agomelatine failed to normalize clock gene expression, and the observed modifying effect on gene expression did not associate with the antidepressant-like effect. This suggests that the antidepressant actions of agomelatine are mainly independent of circadian rhythm synchronization and, in this regard, not superior to traditional antidepressants tested in our model.

Depressive disorders: Processes leading to neurogeneration and potential novel treatments

Mood disorders are wide spread with estimates that one in seven of the population are affected at some time in their life (Kessler et al., 2012). Many of those affected with severe depressive disorders have cognitive deficits which may progress to frank neurodegeneration. There are several peripheral markers shown by patients who have cognitive deficits that could represent causative factors and could potentially serve as guides to the prevention or even treatment of neurodegeneration. Circadian rhythm misalignment, immune dysfunction and oxidative stress are key pathologic processes implicated in neurodegeneration and cognitive dysfunction in depressive disorders. Novel treatments targeting these pathways may therefore potentially improve patient outcomes whereby the primary mechanism of action is outside of the monoaminergic system. Moreover, targeting immune dysfunction, oxidative stress and circadian rhythm misalignment (rather than primarily the monoaminergic system) may hold promise for truly disease modifying treatments that may prevent neurodegeneration rather than simply alleviating symptoms with no curative intent. Further research is required to more comprehensively understand the contributions of these pathways to the pathophysiology of depressive disorders to allow for disease modifying treatments to be discovered.

Parallel Changes in Mood and Melatonin Rhythm Following an Adjunctive Multimodal Chronobiological Intervention With Agomelatine in People With Depression: A Proof of Concept Open Label Study

Background: Agomelatine is a melatonin agonist and 5HT antagonist developed for the treatment of major depressive disorder which also has some effects on the circadian system. Since circadian dysfunctions are thought to play a role in the pathophysiology of depression, some of the mechanism of action of this drug may relate to improvements in circadian rhythms. Objective: This proof of concept open-label study sought to determine if improvements in depressive symptoms following an adjunctive multimodal intervention including agomelatine intake are associated with the magnitude of circadian realignment. This was investigated in young people with depression, a subgroup known to have high rates of delayed circadian rhythms. Methods: Young people with depression received a psychoeducation session about sleep and circadian rhythms, were asked to progressively phase advance their wake up time, and completed an 8 weeks course of agomelatine (25-50 mg). Participants underwent semi-structured psychological assessments, ambulatory sleep-wake monitoring and measurement of melatonin circadian phase before and after the intervention. Results: Twenty-four young adults with depression (17-28 years old; 58% females) completed the study. After the intervention, depressive symptoms were significantly reduced [t ₍₂₃₎ = 6.9, p < 0.001] and, on average, the timing of dim light melatonin onset (DLMO) shifted 3.6 h earlier [t ₍₁₈₎ = 4.4, p < 0.001]. On average, sleep onset was phase shifted 28 min earlier [t ₍₁₉₎ = 2.1, p = 0.047] and total sleep time increased by 24 min [t ₍₁₉₎ = -2.6, p = 0.018]. There was no significant change in wake-up times. A strong correlation (r = 0.69, p = 0.001) was found between the relative improvements in depression severity and the degree of phase shift in DLMO. Conclusion: Although this needs to be replicated in larger randomized controlled trials, these findings suggest that the degree of antidepressant response to a multimodal intervention including psychoeducation and agomelatine intake may be associated with the degree of change in evening melatonin release in young people with depression. This offers promising avenues for targeted treatment based on the prior identification of objective individual characteristics.