Absence of discontinuation symptoms with agomelatine and occurrence of discontinuation symptoms with paroxetine: a randomized, double-blind, placebo-controlled discontinuation study

Effects of discontinuation of serotonergic antidepressants prior to psilocybin therapy versus escitalopram for major depression

BACKGROUND

There is growing evidence for the therapeutic effects of the psychedelic drug psilocybin for major depression. However, due to the lack of safety data on combining psilocybin with selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) and concerns that there may be a negative interaction on efficacy, participants enrolling in psychedelic trials are usually required to discontinue SNRI/SNRIs prior to enrolling.

AIMS

Using data from a recent clinical trial examining the comparative efficacy the psychedelic drug psilocybin (P) combined with approximately 20 h of psychological support to a 6-week (daily) course of the SSRI escitalopram plus matched psychological support for major depressive disorder, we explored the effects of discontinuing SSRI/SNRIs prior to study enrolment on study outcomes.

METHODS

Exploratory post hoc analyses using linear mixed effects model were performed to investigate the discontinuation effect on various validated depression symptom severity scales and well-being. The impact of SSRI/SNRIs discontinuation on the acute psychedelic experience was also explored.

RESULTS/OUTCOMES

In the psilocybin group, there was a reduced treatment effect on all outcome measures for SSRI/SNRIs discontinuers compared with unmedicated patients at trial entry. However, no effects of discontinuation on measures of the acute psychedelic experience were found.

CONCLUSION

Discontinuation of SSRI/SNRIs before psilocybin might diminish response to treatment; however, as we did not test SSRI/SNRI continuation in our trial, we cannot infer such causation. Moreover, the exploratory nature of the analyses makes them hypothesis generating, and not confirmatory. A controlled trial of SSRI/SNRI discontinuation versus continuation prior to psilocybin is urgently required.

Estimating Risk of Antidepressant Withdrawal from a Review of Published Data

Adaptation of the brain to the presence of a drug predicts withdrawal on cessation. The outcome of adaptation is often referred to as 'physical dependence' in pharmacology, as distinct from addiction, although these terms have unfortunately become conflated in some diagnostic guides. Physical dependence to antidepressants may occur in some patients, consistent with the fact that some patients experience withdrawal effects from these medications. It is thought that longer duration of use, higher dose and specific antidepressants affect the risk of antidepressant withdrawal effects as they might cause greater adaptation of the brain. We searched PubMed for relevant systematic reviews and other relevant analyses to summarise existing data on determinants of antidepressant withdrawal incidence, severity and duration. Overall, data were limited. From survey data, increased duration of use was associated with an increased incidence and severity of withdrawal effects, consistent with some evidence from data provided by drug manufacturers. Duration of use may be related to duration of withdrawal effects but data are heterogenous and sparse. Serotonin and noradrenaline reuptake inhibitors and paroxetine are associated with higher risks than other antidepressants, though data for some antidepressants are lacking. Higher doses of antidepressant has some weak association with an increased risk of withdrawal, with some ceiling effects, perhaps reflecting receptor occupancy relationships. Past experience of withdrawal effects is known to predict future risk. Based on these data, we outline a preliminary rubric for determining the risk of withdrawal symptoms for a particular patient, which may have relevance for determining tapering rates. Given the limited scope of the current research, future research should aim to clarify prediction of antidepressant withdrawal risk, especially by examining the risk of withdrawal in long-term users of medication, as well as the severity and duration of effects, to improve the preliminary tool for predictive purposes. Further research into the precise adaptations in long-term antidepressant use may improve the ability to predict withdrawal effects for a particular patient.

SSRI withdrawal syndrome in children and adolescents: a narrative literature review

INTRODUCTION

While there is considerable published evidence regarding the nature and severity of Selective Serotonin Reuptake Inhibitor (SSRI) discontinuation symptoms in the adult population, information relating to the child and adolescent population remains scarce. This narrative review examined the published literature on SSRI withdrawal symptoms in the under-18-year-old age group. MEDLINE and PsycINFO were comprehensively searched from inception to 5 May 2023.

AREAS COVERED

This review highlights the importance of recognizing SSRI withdrawal in children and adolescents and summarizes available literature and guidelines for safe discontinuation.

EXPERT OPINION

Evidence of the presence of SSRI withdrawal phenomenon in children and adolescents mainly originates from case reports and extrapolated adult data. Existing data on SSRI withdrawal syndrome in children and adolescents is therefore limited, and there is a need for formal research in this specific population to establish with more certainty the nature and extent of SSRI withdrawal syndrome. Nevertheless, there is currently enough evidence available for prescribing clinicians to provide psychoeducation to patients and families about the possibility of withdrawal symptoms when SSRI treatment is considered. The need for gradual and planned discontinuation should also be discussed for safe withdrawal.

Agomelatine in the treatment of anhedonia, somatic symptoms, and sexual dysfunction in major depressive disorder

Objective

This study evaluated the treatment outcomes of agomelatine on anhedonic state, anxiety/somatic symptoms, and sexual function in Chinese patients with major depressive disorder (MDD).

Method

In total, 93 adult patients with MDD were enrolled, and 68 of them were included in a prospective, open-label, multicenter clinical study. All patients received agomelatine monotherapy during a 9-week treatment phase. The effectiveness of the treatment was reflected by the improvement of anhedonia and somatic symptoms based on the 17-item Hamilton Depression Rating Scale (HAMD-17). In addition, the Arizona Sexual Dysfunction Scale (ASEX), Sheehan Disability Scale (SDS), and Short Form of Quality-of-Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-SF) were administered to all participants at baseline and at the 3-, 6-, and 9-week follow-ups.

Results

After 9 weeks of treatment with agomelatine, the response and remission rates were 73.5% and 39.7%, respectively. Somatic symptoms significantly improved at week 9 (p < 0.001), and significant effects were also observed on the HAMD anhedonia items (p < 0.001). The patients exhibited lower levels of disease severity (the SDS score dropped from 15.52 ± 4.7 to 7.09 ± 5.62 at week 9; the ASEX score dropped from 21.89 ± 4.06 to 16.19 ± 4.79, p < 0.001) and higher levels of QOL (the Q-LES-Q-SF score dropped from 41.02 ± 5.99 to 50.49 ± 8.57, p < 0.001) during the follow-up. Furthermore, treatment with agomelatine improved depressive symptoms without causing serious adverse events.

Conclusion

These analyses indicate that agomelatine is a treatment option for improving anhedonic status, anxiety/somatic symptoms, and sexual dysfunction in MDD patients.

Distinguishing relapse from antidepressant withdrawal: clinical practice and antidepressant discontinuation studies

We now recognise that withdrawal symptoms from antidepressants are common, and can be severe and long-lasting in some people. Many withdrawal symptoms overlap with symptoms of anxiety or depression, making it difficult to distinguish withdrawal from relapse. We describe how their onset soon after dose reduction, the association of psychological with physical symptoms, their prompt response to reinstatement, and their typical ‘wave’ pattern of onset, peak and resolution can help distinguish withdrawal symptoms from relapse. We also examine evidence that suggests that antidepressant withdrawal symptoms are misdiagnosed as relapse in discontinuation studies aimed at demonstrating the ability of antidepressants to prevent future relapse (relapse prevention properties). In these discontinuation studies people have their antidepressants stopped abruptly, or rapidly, making withdrawal symptoms very likely, and little effort is made to measure withdrawal symptoms or distinguish them from relapse. We conclude that there is currently no robust evidence for the relapse prevention properties of antidepressants, and current guidance might need to be re-evaluated.

Safety and efficacy of agomelatine in children and adolescents with major depressive disorder receiving psychosocial counselling: a double-blind, randomised, controlled, phase 3 trial in nine countries

BACKGROUND

Major depressive disorder is a severe illness that frequently manifests before the age of 18 years, often recurring later in life. Paediatric medical treatment options are scarce. The melatonin receptor agonist and 5-hydroxytryptamine_2C receptor antagonist agomelatine is used to treat adults, and could offer a new therapeutic option for paediatric patients. Therefore, we aimed to investigate the short-term antidepressant efficacy and safety of agomelatine in children and adolescents with major depressive disorder.

METHODS

We performed a 12 week, randomised, double-blind, parallel-group, multicentre, phase 3 trial in 46 specialist psychiatric units or centres in Bulgaria, Finland, Hungary, Poland, Romania, Russia, Serbia, South Africa, and Ukraine. Participants (aged 7-17 years) were eligible if they were unresponsive to psychosocial therapy during the 3-week run-in period (Children's Depression Rating Scale-revised [CDRS-R] score of ≥45). Ethnicity was not recorded. We investigated short-term antidepressant efficacy of agomelatine (10 mg or 25 mg per day) versus placebo with an active control (fluoxetine 10-20 mg depending on symptom severity) after 12 weeks of treatment in children (aged 7-11 years) and adolescents (12-17 years) with major depressive disorder. Patients were randomly assigned (1:1:1:1) to agomelatine 10 mg, agomelatine 25 mg, placebo, or fluoxetine via an interactive response system with permuted-block randomisation. Standardised manualised psychosocial counselling, developed for this trial, was initiated from selection and continued throughout the study, including the open-label extension. All people involved in the conduct of the clinical trial and patients were masked to treatment allocation. Study outcomes were measured using standardised interviews at each study visit. The primary endpoint was change in CDRS-R raw score from baseline to week 12. This study is registered with EudraCT, 2015-002181-23.

FINDINGS

Between Feb 23, 2016, and Jan 14, 2020, 466 individuals were assessed for eligibility and of 400 included patients, 396 (247 [62%] girls, 149 [38%] boys; mean age 13·7 years [SD 2·7]) were analysed (full analysis set). The primary objective was met; 25 mg/day agomelatine (n=94, with n=102 receiving 10 mg/day) resulted in an improvement versus placebo (n=101) in CDRS-R raw score of 4·22 (95% CI 0·63-7·82; p=0·040) at 12 weeks, with a similar effect for fluoxetine (n=99), establishing assay sensitivity. The overall effect was confirmed in adolescents (n=317), but not in children (n=79). No unexpected safety signals were observed with agomelatine, with no significant weight gain or effect on suicidal behaviours.

INTERPRETATION

This first study in a paediatric population supports the efficacy of 25 mg/day agomelatine, in addition to psychosocial counselling, in treating adolescent patients with major depressive disorder, with no unexpected safety signals. This medication could provide another option in the limited psychopharmaceutical repertoire for management of major depressive disorder.

FUNDING

Servier. VIDEO ABSTRACT.

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.

Acute and Persistent Withdrawal Syndromes Following Discontinuation of Psychotropic Medications

Studies on psychotropic medications decrease, discontinuation, or switch have uncovered withdrawal syndromes. The present overview aimed at analyzing the literature to illustrate withdrawal after decrease, discontinuation, or switch of psychotropic medications based on the drug class (i.e., benzodiazepines, nonbenzodiazepine benzodiazepine receptor agonists, antidepressants, ketamine, antipsychotics, lithium, mood stabilizers) according to the diagnostic criteria of Chouinard and Chouinard [Psychother Psychosom. 2015;84(2):63-71], which encompass new withdrawal symptoms, rebound symptoms, and persistent post-withdrawal disorders. All these drugs may induce withdrawal syndromes and rebound upon discontinuation, even with slow tapering. However, only selective serotonin reuptake inhibitors, serotonin noradrenaline reuptake inhibitors, and antipsychotics were consistently also associated with persistent post-withdrawal disorders and potential high severity of symptoms, including alterations of clinical course, whereas the distress associated with benzodiazepines discontinuation appears to be short-lived. As a result, the common belief that benzodiazepines should be substituted by medications that cause less dependence such as antidepressants and antipsychotics runs counter the available literature. Ketamine, and probably its derivatives, may be classified as at high risk for dependence and addiction. Because of the lag phase that has taken place between the introduction of a drug into the market and the description of withdrawal symptoms, caution is needed with the use of newer antidepressants and antipsychotics. Within medication classes, alprazolam, lorazepam, triazolam, paroxetine, venlafaxine, fluphenazine, perphenazine, clozapine, and quetiapine are more likely to induce withdrawal. The likelihood of withdrawal manifestations that may be severe and persistent should thus be taken into account in clinical practice and also in children and adolescents.

Approaches for discontinuation versus continuation of long-term antidepressant use for depressive and anxiety disorders in adults

BACKGROUND

Depression and anxiety are the most frequent indication for which antidepressants are prescribed. Long-term antidepressant use is driving much of the internationally observed rise in antidepressant consumption. Surveys of antidepressant users suggest that 30% to 50% of long-term antidepressant prescriptions had no evidence-based indication. Unnecessary use of antidepressants puts people at risk of adverse events. However, high-certainty evidence is lacking regarding the effectiveness and safety of approaches to discontinuing long-term antidepressants.

OBJECTIVES

To assess the effectiveness and safety of approaches for discontinuation versus continuation of long-term antidepressant use for depressive and anxiety disorders in adults.

SEARCH METHODS

We searched all databases for randomised controlled trials (RCTs) until January 2020.

SELECTION CRITERIA

We included RCTs comparing approaches to discontinuation with continuation of antidepressants (or usual care) for people with depression or anxiety who are prescribed antidepressants for at least six months. Interventions included discontinuation alone (abrupt or taper), discontinuation with psychological therapy support, and discontinuation with minimal intervention. Primary outcomes were successful discontinuation rate, relapse (as defined by authors of the original study), withdrawal symptoms, and adverse events. Secondary outcomes were depressive symptoms, anxiety symptoms, quality of life, social and occupational functioning, and severity of illness.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included 33 studies involving 4995 participants. Nearly all studies were conducted in a specialist mental healthcare service and included participants with recurrent depression (i.e. two or more episodes of depression prior to discontinuation). All included trials were at high risk of bias. The main limitation of the review is bias due to confounding withdrawal symptoms with symptoms of relapse of depression. Withdrawal symptoms (such as low mood, dizziness) may have an effect on almost every outcome including adverse events, quality of life, social functioning, and severity of illness. Abrupt discontinuation Thirteen studies reported abrupt discontinuation of antidepressant. Very low-certainty evidence suggests that abrupt discontinuation without psychological support may increase risk of relapse (hazard ratio (HR) 2.09, 95% confidence interval (CI) 1.59 to 2.74; 1373 participants, 10 studies) and there is insufficient evidence of its effect on adverse events (odds ratio (OR) 1.11, 95% CI 0.62 to 1.99; 1012 participants, 7 studies; I² = 37%) compared to continuation of antidepressants, without specific assessment of withdrawal symptoms. Evidence about the effects of abrupt discontinuation on withdrawal symptoms (1 study) is very uncertain. None of these studies included successful discontinuation rate as a primary endpoint. Discontinuation by "taper" Eighteen studies examined discontinuation by "tapering" (one week or longer). Most tapering regimens lasted four weeks or less. Very low-certainty evidence suggests that "tapered" discontinuation may lead to higher risk of relapse (HR 2.97, 95% CI 2.24 to 3.93; 1546 participants, 13 studies) with no or little difference in adverse events (OR 1.06, 95% CI 0.82 to 1.38; 1479 participants, 7 studies; I² = 0%) compared to continuation of antidepressants, without specific assessment of withdrawal symptoms. Evidence about the effects of discontinuation on withdrawal symptoms (1 study) is very uncertain. Discontinuation with psychological support Four studies reported discontinuation with psychological support. Very low-certainty evidence suggests that initiation of preventive cognitive therapy (PCT), or MBCT, combined with "tapering" may result in successful discontinuation rates of 40% to 75% in the discontinuation group (690 participants, 3 studies). Data from control groups in these studies were requested but are not yet available. Low-certainty evidence suggests that discontinuation combined with psychological intervention may result in no or little effect on relapse (HR 0.89, 95% CI 0.66 to 1.19; 690 participants, 3 studies) compared to continuation of antidepressants. Withdrawal symptoms were not measured. Pooling data on adverse events was not possible due to insufficient information (3 studies). Discontinuation with minimal intervention Low-certainty evidence from one study suggests that a letter to the general practitioner (GP) to review antidepressant treatment may result in no or little effect on successful discontinuation rate compared to usual care (6% versus 8%; 146 participants, 1 study) or on relapse (relapse rate 26% vs 13%; 146 participants, 1 study). No data on withdrawal symptoms nor adverse events were provided. None of the studies used low-intensity psychological interventions such as online support or a changed pharmaceutical formulation that allows tapering with low doses over several months. Insufficient data were available for the majority of people taking antidepressants in the community (i.e. those with only one or no prior episode of depression), for people aged 65 years and older, and for people taking antidepressants for anxiety.

AUTHORS' CONCLUSIONS

Currently, relatively few studies have focused on approaches to discontinuation of long-term antidepressants. We cannot make any firm conclusions about effects and safety of the approaches studied to date. The true effect and safety are likely to be substantially different from the data presented due to assessment of relapse of depression that is confounded by withdrawal symptoms. All other outcomes are confounded with withdrawal symptoms. Most tapering regimens were limited to four weeks or less. In the studies with rapid tapering schemes the risk of withdrawal symptoms may be similar to studies using abrupt discontinuation which may influence the effectiveness of the interventions. Nearly all data come from people with recurrent depression.   There is an urgent need for trials that adequately address withdrawal confounding bias, and carefully distinguish relapse from withdrawal symptoms. Future studies should report key outcomes such as successful discontinuation rate and should include populations with one or no prior depression episodes in primary care, older people, and people taking antidepressants for anxiety and use tapering schemes longer than 4 weeks.

[Pharmacotherapy of anxiety disorders-Guideline-conform treatment and new developments]

Besides cognitive behavioral therapy (CBT), psychopharmacotherapy belongs to the first-line treatment approaches for anxiety disorders according to all national and international guidelines. According to studies and meta-analyses, modern antidepressants in particular have been proven to be effective. Depending on the substance, there are approvals for panic disorder, generalized anxiety disorder and social phobia. There are also approvals for other substance groups, e.g. anticonvulsants for generalized anxiety disorder. Benzodiazepines should be used with caution in view of the risk of dependency. Although effective and well-tolerated medications are available, up to 30% of patients still do not respond or do not respond adequately to treatment. Consequently, research efforts to develop new substances are important. Based on a better understanding of the complex neurobiological mechanisms underlying anxiety disorders, a large number of substances are currently undergoing clinical trials. Modulators of current and new transmitter systems, in particular the glutamatergic and the endocannabinoid systems as well as neuropeptides, are being discussed as innovative substances. Strategies are also being investigated which, in combination with psychotherapy, aim at optimizing fear extinction memory. First studies are also underway on the use of psychedelic agents in combination with psychotherapy for anxiety.

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.

Antidepressant Withdrawal and Rebound Phenomena

BACKGROUND

Antidepressants are among the most commonly prescribed drugs worldwide. They are often discontinued, frequently without the knowledge of the prescribing physician. It is, therefore, important for physicians to be aware of the withdrawal and rebound phenomena that may arise, in order to prevent these phenomena, treat them when necessary, and counsel patients appropriately.

METHODS

This review is based on a comprehensive, structured literature search on antidepressant withdrawal phenomena that we carried out in the CENTRAL, PubMed (Medline), and Embase databases. We classified the relevant publications and reports by their methodological quality.

RESULTS

Out of a total of 2287 hits, there were 40 controlled trials, 38 cohort studies and retrospective analyses, and 271 case reports that met the inclusion criteria. Withdrawal manifestations are usually mild and self-limiting; common ones include dizziness, headache, sleep disturbances, and mood swings. More serious or pro- longed manifestations rarely arise. There is an increased risk with MAO inhibitors, tricyclic antidepressants, venlafaxine, and paroxetine; on the other hand, for agome- latine and fluoxetine, abrupt discontinuation seems to be unproblematic. There is also some evidence of rebound phenomena, i.e., of higher relapse rates or especially severe relapses of depression after the discontinuation of an anti- depressant.

CONCLUSION

A robust evidence base now indicates that there can be acute with- drawal phenomena when antidepressants are discontinued. Putative rebound phenomena have not been adequately studied to date. It is recommended that antidepressants should be tapered off over a period of more than four weeks.

Agomelatine: A novel mechanism of antidepressant action involving the melatonergic and the serotonergic system

The clinical finding that depressive disorders are often associated with desynchronization of internal rhythms has encouraged the idea that resetting normal circadian rhythms may have antidepressant potential. Agomelatine, a naphthalene analog of melatonin, is both an agonist of human cloned melatonergic MT1 and MT2 receptors and a serotonin 5-HT2C receptor antagonist. Agomelatine combines zeitgeber (synchroniser of the circadian system) activity with neurotransmitter augmentation properties (enhances the levels of dopamine and noradrenaline in frontal cortex). The efficacy of agomelatine in treating depression has been shown in three short-term, pivotal, randomized, placebo–controlled studies. These studies have demonstrated agomelatine to be efficacious in Major Depressive Disorder at the standard dose of 25 mg/day, with the possibility of increasing doses to 50 mg/day in those patients with insufficient improvement. The number of adverse events during the treatment period was comparable to placebo. Four studies have shown the positive effect of agomelatine on sleep continuity and quality and shortening of sleep latency. Despite these promising data, further studies are needed to examine agomelatine's efficacy over a longer treatment period.

A systematic review into the incidence, severity and duration of antidepressant withdrawal effects: Are guidelines evidence-based?

INTRODUCTION

The U.K.'s current National Institute for Health and Care Excellence and the American Psychiatric Association's depression guidelines state that withdrawal reactions from antidepressants are 'self-limiting' (i.e. typically resolving between 1 and 2weeks). This systematic review assesses that claim.

METHODS

A systematic literature review was undertaken to ascertain the incidence, severity and duration of antidepressant withdrawal reactions. We identified 24 relevant studies, with diverse methodologies and sample sizes.

RESULTS

Withdrawal incidence rates from 14 studies ranged from 27% to 86% with a weighted average of 56%. Four large studies of severity produced a weighted average of 46% of those experiencing antidepressant withdrawal effects endorsing the most extreme severity rating on offer. Seven of the ten very diverse studies providing data on duration contradict the U.K. and U.S.A. withdrawal guidelines in that they found that a significant proportion of people who experience withdrawal do so for more than two weeks, and that it is not uncommon for people to experience withdrawal for several months. The findings of the only four studies calculating mean duration were, for quite heterogeneous populations, 5days, 10days, 43days and 79weeks.

CONCLUSIONS

We recommend that U.K. and U.S.A. guidelines on antidepressant withdrawal be urgently updated as they are clearly at variance with the evidence on the incidence, severity and duration of antidepressant withdrawal, and are probably leading to the widespread misdiagnosing of withdrawal, the consequent lengthening of antidepressant use, much unnecessary antidepressant prescribing and higher rates of antidepressant prescriptions overall. We also recommend that prescribers fully inform patients about the possibility of withdrawal effects.

Tapering of SSRI treatment to mitigate withdrawal symptoms

All classes of drug that are prescribed to treat depression are associated with withdrawal syndromes. SSRI withdrawal syndrome occurs often and can be severe, and might compel patients to recommence their medication. Although the withdrawal syndrome can be differentiated from recurrence of the underlying disorder, it might also be mistaken for recurrence, leading to long-term unnecessary medication. Guidelines recommend short tapers, of between 2 weeks and 4 weeks, down to therapeutic minimum doses, or half-minimum doses, before complete cessation. Studies have shown that these tapers show minimal benefits over abrupt discontinuation, and are often not tolerated by patients. Tapers over a period of months and down to doses much lower than minimum therapeutic doses have shown greater success in reducing withdrawal symptoms. Other types of medication associated with withdrawal, such as benzodiazepenes, are tapered to reduce their biological effect at receptors by fixed amounts to minimise withdrawal symptoms. These dose reductions are done with exponential tapering programmes that reach very small doses. This method could have relevance for tapering of SSRIs. We examined the PET imaging data of serotonin transporter occupancy by SSRIs and found that hyperbolically reducing doses of SSRIs reduces their effect on serotonin transporter inhibition in a linear manner. We therefore suggest that SSRIs should be tapered hyperbolically and slowly to doses much lower than those of therapeutic minimums, in line with tapering regimens for other medications associated with withdrawal symptoms. Withdrawal symptoms will then be minimised.

Antidepressants, withdrawal, and addiction; where are we now?

Controversy continues with regard to antidepressants and withdrawal. Recent debates have focused on the prevalence and length of withdrawal, and some continue to state that withdrawal from these compounds constitutes 'addiction'. In this editorial we examine the evidence underlying these recent debates. We acknowledge gaps in knowledge, and make suggestions for how the field can progress.

Sub-Acute Oral Toxicity of a Novel Derivative of Agomelatine in Rats in a Sex-Dependent Manner

Agomelatine (AGO) is a new type of antidepressant with demonstrated antidepressant effects and a unique modulating circadian rhythm action. However, AGO has hepatotoxicity, which limits its clinical application. In order to develop new drugs that cause less liver injury than AGO, a series of derivatives were synthesized; compound GW117 was screened from derivatives due to its high receptor affinity. This study will investigate its sub-acute oral toxicity profile in rats in a sex-dependent manner. GW117 and AGO was administrated by gavage (200, 400, or 800 mg/kg/day) for 28 days. Hematological, biochemical tests, organ weights, histopathological examinations were carried out, the results showed that AGO and GW117 had adverse effects on platelet, liver and kidney, and had sex-differences in some indicators. Hematological tests showed that AGO and GW117 reduced the platelet count in male animals but had no effect in females. AGO increased plasma alanine aminotransferase (ALT) and total bilirubin in male animals, and GW117 had no effect on these two indicators. For females, AGO moderately elevated ALT, alkaline phosphatase (ALP), and total bilirubin, while GW117 only elevated ALP slightly. Two drugs could increase liver weight and coefficient, and cause liver pathological injury, including hepatic sinusoidal dilatation, hepatocyte fatty deposition and dotted cell necrosis in two genders. AGO caused mild to moderate hepatocyte and hepatobiliary injury in both genders, while only a mild hepatobiliary injury was caused by GW117 in females. Renal function tests showed that both drugs can increase blood urea nitrogen levels in males, while AGO, but not GW117, can slightly increase blood creatinine and urea nitrogen in females. The kidney weight and coefficient could be significantly increased by two drugs in males, and by AGO medium and GW117 high and low doses in females. The kidney pathological damage was mainly characterized by tubule dilatation, a thinning of the renal cortex. Kidney damage caused by GW117 was less than that of AGO, and there was no sex-difference. In summary, GW117 can cause mild liver and kidney damage in both genders, as well as mild platelets reduction in males, while degree of damage is less severe than AGO. Therefore, as an excellent derivative, GW117 deserves further development as an antidepressant.

[Antidepressants: the goals and possibilities of therapy]

Antidepressants are among the most commonly prescribed drugs due to their effectivenes in treating depression and anxiety disorders. One of the reasons for early discontinuation of taking antidepressants are side-effects. Agomelatine is a relatively novel antidepressant with high efficacy and good tolerance. Clinical effects of agomelatine include a reduction in symptoms of depression, anti-anxiety and hypnotic effects, as well as the rapid elimination of anhedonia, which determines high adherence to therapy, restoration of normal social functioning, and complete remission of disease.

Managing Antidepressant Discontinuation: A Systematic Review

PURPOSE

We aimed to determine the effectiveness of interventions to manage antidepressant discontinuation, and the outcomes for patients.

METHODS

We conducted a systematic review with narrative synthesis and meta-analysis of studies published to March 2017. Studies were eligible for inclusion if they were randomized controlled trials, quasi-experimental studies, or observational studies assessing interventions to facilitate discontinuation of antidepressants for depression in adults. Our primary outcomes were antidepressant discontinuation and discontinuation symptoms. Secondary outcomes were relapse/recurrence; quality of life; antidepressant reduction; and sexual, social, and occupational function.

RESULTS

Of 15 included studies, 12 studies (8 randomized controlled trials, 2 single-arm trials, 2 retrospective cohort studies) were included in the synthesis. None were rated as having high risk for selection or detection bias. Two studies prompting primary care clinician discontinuation with antidepressant tapering guidance found 6% and 7% of patients discontinued, vs 8% for usual care. Six studies of psychological or psychiatric treatment plus tapering reported cessation rates of 40% to 95%. Two studies reported a higher risk of discontinuation symptoms with abrupt termination. At 2 years, risk of relapse/recurrence was lower with cognitive behavioral therapy plus taper vs clinical management plus taper (15% to 25% vs 35% to 80%: risk ratio = 0.34; 95% CI, 0.18-0.67; 2 studies). Relapse/recurrence rates were similar for mindfulness-based cognitive therapy with tapering and maintenance antidepressants (44% to 48% vs 47% to 60%; 2 studies).

CONCLUSIONS

Cognitive behavioral therapy or mindfulness-based cognitive therapy can help patients discontinue antidepressants without increasing the risk of relapse/recurrence, but are resource intensive. More scalable interventions incorporating psychological support are needed.

12-week double-blind randomized multicenter study of efficacy and safety of agomelatine (25-50 mg/day) versus escitalopram (10-20 mg/day) in out-patients with severe generalized anxiety disorder

Treatment of severely symptomatic patients with generalized anxiety disorder (GAD) raises particular concerns for clinicians. This 12-week double-blind study evaluated the efficacy of agomelatine (25-50 mg/day) in the treatment of patients with severe GAD, using escitalopram (10-20 mg) as active comparator. The primary outcome measure was the change from baseline of the total score on the Hamilton Anxiety scale (HAM-A) at week 12. Secondary outcome measures included rate of response to treatment (at least 50% score reduction from baseline) in the HAM-A psychic and somatic anxiety sub-scores, Clinical Global Impression severity and change scores, the Toronto Hospital Alertness Test, the Snaith-Hamilton Pleasure Scale, and the Leeds Sleep Evaluation Questionnaire Scores. Sixty one clinical centers (Australia, Canada, Czech Republic, Finland, Germany, Hungary, Poland, Russia, Slovakia) participated from April 2013 to February 2015. Patient characteristics and demographic data were comparable between treatment groups. Both treatments were associated with a clinically significant decrease in HAM-A total score at week 12; the non-inferiority of agomelatine versus escitalopram was not demonstrated (E(SE) = -0.91(0.69), 95%CI = [-2.26, 0.44], p = 0.195). At week 12, the response rate was 60.9% in the agomelatine group, and 64.8% in the escitalopram group. In both treatment arms, HAM-A psychic and somatic anxiety scores decreased, alertness and sleep parameters improved, and ability to experience pleasure increased. In these secondary outcome measures, there were no significant differences between the treatment groups. Agomelatine was well-tolerated, with a lower incidence of adverse events than escitalopram. Agomelatine and escitalopram are efficacious in treating GAD patients with severe symptoms.

Treatment of anxiety disorders

Anxiety disorders (generalized anxiety disorder, panic disorder/agoraphobia, social anxiety disorder, and others) are the most prevalent psychiatric disorders, and are associated with a high burden of illness. Anxiety disorders are often underrecognized and undertreated in primary care. Treatment is indicated when a patient shows marked distress or suffers from complications resulting from the disorder. The treatment recommendations given in this article are based on guidelines, meta-analyses, and systematic reviews of randomized controlled studies. Anxiety disorders should be treated with psychological therapy, pharmacotherapy, or a combination of both. Cognitive behavioral therapy can be regarded as the psychotherapy with the highest level of evidence. First-line drugs are the selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors. Benzodiazepines are not recommended for routine use. Other treatment options include pregabalin, tricyclic antidepressants, buspirone, moclobemide, and others. After remission, medications should be continued for 6 to 12 months. When developing a treatment plan, efficacy, adverse effects, interactions, costs, and the preference of the patient should be considered.

Long-term chamomile (Matricaria chamomilla L.) treatment for generalized anxiety disorder: A randomized clinical trial

BACKGROUND

Generalized Anxiety Disorder (GAD) is one of the most common anxiety disorders treated in primary care, yet current therapies have limited efficacy and substantial side effects.

PURPOSE

To evaluate long-term chamomile (Matricaria chamomilla L.) use for prevention of GAD symptom relapse.

METHODS

Outpatients from primary care practices and local communities with a primary diagnosis of moderate-to-severe GAD were enrolled for this two-phase study at a large US academic medical center. During Phase 1, eligible participants received 12 weeks of open-label therapy with chamomile pharmaceutical grade extract 1500mg (500mg capsule 3 times daily). During Phase 2, treatment responders were randomized to either 26 weeks of continuation chamomile therapy or placebo in a double-blinded, placebo-substitution design. The primary outcome was time to relapse during continuation therapy, analyzed using Cox proportional hazards. Secondary outcomes included the proportion who relapsed, treatment-emergent adverse events, and vital sign changes. This study is registered at ClinicalTrials.gov, identifier NCT01072344.

RESULTS

Between March 1, 2010, and June 30, 2015, we enrolled 179 participants. Of those, 93 (51.9%) were responders and agreed to continue in the double-blind randomized controlled trial. A numerically greater number of placebo-switched (n=12/47; 25.5%) versus chamomile-continuation (n = 7/46; 15.2%) participants relapsed during follow-up. Mean time to relapse was 11.4 ± 8.4 weeks for chamomile and 6.3 ± 3.9 weeks for placebo. Hazard of relapse was non-significantly lower for chamomile (hazard ratio, 0.52; 95% CI, 0.20-1.33; P = 0.16). During follow-up, chamomile participants maintained significantly lower GAD symptoms than placebo (P = 0.0032), with significant reductions in body weight (P = 0.046) and mean arterial blood pressure (P = 0.0063). Both treatments had similar low adverse event rates.

CONCLUSIONS

Long-term chamomile was safe and significantly reduced moderate-to-severe GAD symptoms, but did not significantly reduce rate of relapse. Our limited sample size and lower than expected rate of placebo group relapse likely contributed to the non-significant primary outcome finding. Possible chamomile superiority over placebo requires further examination in large-scale studies.

Characterisation of Agomelatine-Induced Increase in Liver Enzymes: Frequency and Risk Factors Determined from a Pooled Analysis of 7605 Treated Patients

BACKGROUND

Antidepressant-induced liver injury is a major concern and a liver monitoring scheme has been recommended by the European Medicines Agency for agomelatine.

OBJECTIVE

The objective of this study was to assess the liver safety and identify the characteristics of patients who developed a significant increase in transaminases whilst taking agomelatine.

METHOD

A retrospective pooled analysis of changes in transaminase levels in 9234 patients treated with agomelatine (25 or 50 mg/day; n = 7605) or placebo (n = 1629) from 49 phase II and III studies was undertaken. A significant increase in transaminase levels was defined as an increase to >3 times the upper limit of normal (ULN) (>3 × ULN). Final causality was determined in a case-by-case review by five academic experts.

RESULTS

Serum transaminases increased to >3 × ULN in 1.3 and 2.5 % of patients treated with 25 and 50 mg of agomelatine, respectively, compared with 0.5 % for placebo. The onset of increased transaminases occurred before 12 weeks in 64 % of patients. The median time to recovery (to ≤2 × ULN) was 14 days following treatment withdrawal. Liver function tests recovered in 36.1 % of patients despite continuation of agomelatine, suggesting the presence of a liver adaptive mechanism. No cases of acute liver failure or fatal outcome occurred. Patients with elevated transaminases at baseline, secondary to obesity/fatty liver disease, had an equally increased risk of developing further elevations of transaminases with agomelatine and placebo.

CONCLUSION

Incidence of abnormal transaminases was low and dose dependent. No specific population was identified regarding potential risk factors. Withdrawal of agomelatine led to rapid recovery, and some patients exhibited an adaptive phenomenon. Overall, in clinical trials, the liver profile of agomelatine seems safe when serum transaminases are monitored.

Characterizing novel metabolic pathways of melatonin receptor agonist agomelatine using metabolomic approaches

Agomelatine (AGM), an analog of melatonin, is a potential agonist at melatonin receptors 1/2 and a selective antagonist at 5-hydroxytryptamine 2C receptors. AGM is widely used for the treatment of major depressive episodes in adults. However, multiple adverse effects associated with AGM have been reported in clinical practice. It is little known about AGM metabolism in vitro and in vivo, although metabolism plays a pivotal role in its efficacy and safety. To elucidate metabolic pathways of AGM, we systemically investigated AGM metabolism and its bioactivation in human liver microsomes (HLM) and mice using metabolomic approaches. We identified thirty-eight AGM metabolites and adducts, among which thirty-two are novel. In HLM, we uncovered five GSH-trapped adducts and two semicarbazide-trapped aldehydes. Moreover, we characterized three N-acetyl cysteine conjugated-AGM adducts in mouse urine and feces, which were formed from the degradation of AGM_GSH adducts. Using recombinant CYP450 isoenzymes and chemical inhibitors, we demonstrated that CYP1A2 and CYP3A4 are primary enzymes contributing to the formation of AGM_GSH adducts and AGM_hydrazones. This study provided a global view of AGM metabolism and identified the novel pathways of AGM bioactivation, which could be utilized for further understanding the mechanism of adverse effects related to AGM and possible drug-drug interactions.

A review of the management of antidepressant discontinuation symptoms

Strong evidence supports the existence of a discontinuation syndrome following the withdrawal of antidepressant medication, particularly second-generation antidepressants. The syndrome is a common phenomenon and guidance as to best avoid the symptoms is essential for both practitioners and patients. The current study reviewed the available literature on the best methods of discontinuation for antidepressants in order to avoid or prevent the occurrence of any unpleasant side effects associated with antidepressant withdrawal. Accordingly, an electronic search of the PubMed/MedLine database and Google Scholar was conducted to find relevant literature published within the last 10 years. From this, 18 related articles were identified; five clinical studies, one case series, one consensus panel's recommendations and 11 literature reviews. Of the articles reviewed there is a general consensus as to tapering the drug slowly over a period of weeks or months. Also, in those patients who experience severe symptoms the drug should be reinstated and discontinued more gradually. The discontinuation syndrome does not occur as frequently or severely with longer-acting agents such as fluoxetine and therefore it is recommended that switching to this drug prior to withdrawal may be advisable. The articles reviewed also emphasize the need for patient education and reassurance throughout the discontinuation process. One in particular adds that cognitive behavioural therapy may be a useful tool in easing the patients' distress. However, this review highlights the lack of controlled data to support the available guidelines. Furthermore, the guidance which is available is somewhat conflicting. Research approaches should address this issue as well as develop appropriate methods of withdrawal for specific drugs.

Withdrawal Symptoms after Selective Serotonin Reuptake Inhibitor Discontinuation: A Systematic Review

Background: Selective serotonin reuptake inhibitors (SSRI) are widely used in medical practice. They have been associated with a broad range of symptoms, whose clinical meaning has not been fully appreciated. Methods: The PRISMA guidelines were followed to conduct a systematic review of the literature. Titles, abstracts, and topics were searched using the following terms: 'withdrawal symptoms' OR 'withdrawal syndrome' OR 'discontinuation syndrome' OR 'discontinuation symptoms', AND 'SSRI' OR 'serotonin' OR 'antidepressant' OR 'paroxetine' OR 'fluoxetine' OR 'sertraline' OR 'fluvoxamine' OR 'citalopram' OR 'escitalopram'. The electronic research literature databases included CINAHL, the Cochrane Library, PubMed and Web-of-Science from inception of each database to July 2014. Results: There were 15 randomized controlled studies, 4 open trials, 4 retrospective investigations, and 38 case reports. The prevalence of the syndrome was variable, and its estimation was hindered by a lack of case identification in many studies. Symptoms typically occur within a few days from drug discontinuation and last a few weeks, also with gradual tapering. However, many variations are possible, including late onset and/or longer persistence of disturbances. Symptoms may be easily misidentified as signs of impending relapse. Conclusions: Clinicians need to add SSRI to the list of drugs potentially inducing withdrawal symptoms upon discontinuation, together with benzodiazepines, barbiturates, and other psychotropic drugs. The term 'discontinuation syndrome' that is currently used minimizes the potential vulnerabilities induced by SSRI and should be replaced by 'withdrawal syndrome'. © 2015 S. Karger AG, Basel.

Incidence and Timing of Taper/Posttherapy-Emergent Adverse Events Following Discontinuation of Desvenlafaxine 50 mg/d in Patients With Major Depressive Disorder

OBJECTIVE

The purpose of this post hoc analysis was to evaluate the incidence and timing of taper/posttherapy-emergent adverse events (TPAEs) following discontinuation of long-term treatment with desvenlafaxine (administered as desvenlafaxine succinate).

METHOD

This was a phase 4, randomized, double-blind, placebo-controlled study conducted at 38 research centers within the United States between March 2010 and February 2011. Adult outpatients with major depressive disorder (MDD; DSM-IV-TR criteria) who completed 24 weeks of open-label treatment with desvenlafaxine 50 mg/d were randomly assigned to 1 of 3 groups for the double-blind taper phase: desvenlafaxine 50 mg/d for 4 weeks (no discontinuation), desvenlafaxine 25 mg/d for 1 week followed by placebo for 3 weeks (taper), or placebo for 4 weeks (abrupt discontinuation). The primary endpoint, Discontinuation-Emergent Signs and Symptoms Scale (DESS) score over the first 2 weeks of the taper phase, was described previously. Secondary assessments included incidence and timing of TPAEs (any adverse event that started or increased in severity during the double-blind phase) and the percentage of patients who could not continue the taper phase due to discontinuation symptoms. The Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR16) assessed MDD status.

RESULTS

A total of 480 patients enrolled in the open-label phase; the full analysis set included 357 patients (taper, n = 139; abrupt discontinuation, n = 146; no discontinuation, n = 72). TPAEs occurred in all groups through week 4. The incidence of any TPAE was lower for taper versus abrupt discontinuation at week 1 (P < .001), similar at week 2, and lower for taper versus abrupt discontinuation at weeks 3 and 4 (P ≤ .034). The most common TPAEs (incidence ≥ 3%) in the taper group were nausea and headache (3% each) at week 1 and dizziness (5%) and headache (4%) at week 2. The most common TPAEs in the abrupt discontinuation group were dizziness (8%), headache (8%), nausea (4%), irritability (3%), and diarrhea (3%) at week 1 and headache (3%) at weeks 2 and 3. The most common TPAE in the no discontinuation group was nausea (6%) at week 2.

CONCLUSION

The overall incidence of any TPAE was lower in the taper versus abrupt discontinuation groups.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01056289.

How to switch to agomelatine after an unsuccessful try with paroxetine or venlafaxine

OBJECTIVE/INTRODUCTION

The present trial informs clinicians about switching conditions with the antidepressant agomelatine after the failure of a treatment with either paroxetine or venlafaxine.

METHODS

The total number of discontinuation-emergent symptoms, according to the Discontinuation-Emergent Signs and Symptoms checklist, was compared in double-blind conditions after 3 switching options: immediate substitution or initiation of agomelatine (25 mg/day p.o.) with either a short- or long-tapering of the previous drug. Secondary objectives included tolerability and safety assessments and the early clinical benefit after the switch.

RESULTS

For all switching options, a withdrawal syndrome was observed 1 week after cessation of the selective serotonin reuptake inhibitor (SSRI)/serotonin-norepinephrine reuptake inhibitor (SNRI) treatment. Psychic symptoms were the most frequently reported, and somatic symptoms were comparatively few. Early discontinuation symptoms after cessation of SSRI/SNRI treatment did not prejudice the antidepressant benefits of agomelatine over 8 weeks.

CONCLUSIONS

Both abrupt and start-taper switching with agomelatine are options in everyday practice for those patients who have not responded to either paroxetine or venlafaxine. However, regardless of the switching strategy, the present double-blind study shows that early discontinuation symptoms that arise upon cessation of SSRI/SNRI can alter the patients' perception of the clinical benefit of the new antidepressant. Both practitioners and patients must be warned about these early discontinuation symptoms to prevent the symptoms from being confounded with a lack of therapeutic benefit of the new treatment.

Agomelatine beyond borders: current evidences of its efficacy in disorders other than major depression

Agomelatine, a melatonergic antidepressant with a rapid onset of action, is one of the most recent drugs in the antidepressant category. Agomelatine's antidepressant actions are attributed to its sleep-promoting and chronobiotic actions mediated by MT1 and MT2 receptors present in the suprachiasmatic nucleus, as well as to its effects on the blockade of 5-HT2c receptors. Blockade of 5-HT2c receptors causes release of both noradrenaline and dopamine at the fronto-cortical dopaminergic and noradrenergic pathways. The combined actions of agomelatine on MT1/MT2 and 5-HT2c receptors facilitate the resynchronization of altered circadian rhythms and abnormal sleep patterns. Agomelatine appeared to be effective in treating major depression. Moreover, evidence exists that points out a possible efficacy of such drug in the treatment of bipolar depression, anxiety disorders, alcohol dependence, migraines etc. Thus, the aim of this narrative review was to elucidate current evidences on the role of agomelatine in disorders other than major depression.

Agomelatine in the treatment of major depressive disorder: an assessment of benefits and risks

Agomelatine (AGM) was approved for the treatment of major depressive disorder (MDD) in adults by the European Medicines Agency (EMA) in February 2009. It is an analogue of melatonin and features a unique pharmacodynamic profile with agonism on both types of melatonergic receptors (MT1/MT2) and antagonism at serotonergic 5-HT2C receptors. There is, however, an ongoing debate regarding the efficacy and safety of this novel antidepressant agent, originally evoked by claims of a significant publication bias underlying the assessment of AGM being an effective antidepressant. Indeed, two recent comprehensive metaanalyses of published and unpublished clinical trials found evidence for a relevant publication bias. However, due to its statistically significant advantage over placebo based on the results of these metaanalyses AGM must be referred to as an effective antidepressant agent in the acute phase of MDD. However, the effect sizes of AGM in the treatment of MDD were evaluated as being small in comparison to other antidepressant agents. In addition, there is insufficient evidence for the efficacy of AGM in relapse prevention of MDD. Apart from efficacy issues, AGM appears to have the potential to exhibit severe hepatotoxicity (the EMA has identified AGM-associated “hepatotoxic reactions” as a new safety concern in September 2013) that is currently poorly understood. Considering these aspects, it seems inappropriate to evaluate AGM as an antidepressant agent of first choice. Nevertheless, its unique mechanism of action with particular sleep modulating effects may represent a specific treatment strategy for patients with particular characteristics; further studies with thorough characterization of patients are needed to test this hypothesis.

Long-Term Chamomile Therapy of Generalized Anxiety Disorder: A Study Protocol for a Randomized, Double-Blind, Placebo- Controlled Trial

BACKGROUND

Anxiety symptoms are among the most common reasons for consumers to use Complementary and Alternative Medicine (CAM) therapy. Although many botanicals have been proposed as putative remedies for anxiety symptoms, there has been a paucity of controlled trials of these remedies. A preliminary study of the anxiolytic effect of Chamomile (Matricaria recutita) in humans suggests that chamomile may have anxiolytic and antidepressant activity. We now seek to conduct a 5-year randomized, double-blind, placebo-substitution study to examine the short and long-term safety and efficacy of chamomile extract in Generalized Anxiety Disorder (GAD).

METHODS/DESIGN

180 subjects with moderate to severe GAD will receive initial open-label pharmaceutical-grade chamomile extract 500-1,500 mg daily for 8 weeks. Responders to treatment who remain well for an additional 4 weeks of consolidation therapy, will be randomized to double-blind continuation therapy with either chamomile extract 500-1,500 mg daily or placebo for an additional 26 weeks. The primary outcome will be the time to relapse during study continuation therapy in each treatment condition. Secondary outcomes will include the proportion of subjects in each treatment condition who relapse, as well as the proportion of subjects with treatment-emergent adverse events. Quality of life ratings will also be compared between treatment conditions during short and long-term therapy.

DISCUSSION

Many individuals with mental disorders decline conventional therapy and seek CAM therapies for their symptoms. Thus, the identification of effective CAM therapy is of relevance to reducing the burden of mental illness. This study builds upon our prior findings of significant superiority of chamomile versus placebo in reducing GAD symptoms. We now extend these preliminary findings by conducting a randomized long-term safety and efficacy study of chamomile in GAD.

A randomised, double-blind study in adults with major depressive disorder with an inadequate response to a single course of selective serotonin reuptake inhibitor or serotonin-noradrenaline reuptake inhibitor treatment switched to vortioxetine or agomelatine

OBJECTIVE

This randomised, double-blind, 12-week study compared efficacy and tolerability of flexible-dose treatment with vortioxetine(10-20 mg/day) versus agomelatine (25-50 mg/day) in major depressive disorder patients with inadequate response to selective serotonin reuptake inhibitor (SSRI)/serotonin-noradrenaline reuptake inhibitor (SNRI) monotherapy.

METHODS

Patients were switched directly from SSRI/SNRI to vortioxetine or agomelatine. Primary endpoint was change from baseline to week 8 in the Montgomery-Åsberg Depression Rating Scale (MADRS) total score analysed by mixed model for repeated measurements, using a noninferiority test followed by a superiority test. Secondary endpoints included response and remission rates, anxiety symptoms(Hamilton Anxiety Rating Scale), Clinical Global Impression, overall functioning (Sheehan Disability Scale), health-related quality of life(EuroQol 5 Dimensions), productivity (work limitation questionnaire) and family functioning (Depression and Family Functioning Scale).

RESULTS

Primary endpoint noninferiority was established and vortioxetine (n = 252) was superior to agomelatine (n = 241) by 2.2 MADRS points (p<0.01). Vortioxetine was also significantly superior in response and remission rates at weeks 8 and 12; MADRS, Hamilton Anxiety Rating Scale, Clinical Global Impression, Sheehan Disability Scale and EuroQol 5 Dimensions scores at week 4 onwards; work limitation questionnaire at week 8 and Depression and Family Functioning Scale at weeks 8 and 12. Fewer patients withdrew because of adverse events with vortioxetine (5.9% vs 9.5%). Adverse events (incidence ≥5%) were nausea, headache, dizziness and somnolence.

CONCLUSIONS

Vortioxetine was noninferior and significantly superior to agomelatine in major depressive disorder patients with previous inadequate response to a single course of SSRI/SNRI monotherapy. Vortioxetine was safe and well tolerated.

Agomelatine: mechanism of action and pharmacological profile in relation to antidepressant properties

Agomelatine behaves both as a potent agonist at melatonin MT1 and MT2 receptors and as a neutral antagonist at 5-HT2C receptors. Accumulating evidence in a broad range of experimental procedures supports the notion that the psychotropic effects of agomelatine are due to the synergy between its melatonergic and 5-hydroxytryptaminergic effects. The recent demonstration of the existence of heteromeric complexes of MT1 and MT2 with 5-HT2C receptors at the cellular level may explain how these two properties of agomelatine translate into a synergistic action that, for example, leads to increases in hippocampal proliferation, maturation and survival through modulation of multiple cellular pathways (increase in trophic factors, synaptic remodelling, glutamate signalling) and key targets (early genes, kinases). The present review focuses on the pharmacological properties of this novel antidepressant. Its mechanism of action, strikingly different from that of conventional classes of antidepressants, opens perspectives towards a better understanding of the physiopathological bases underlying depression.

Comparison of agomelatine and selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitors in major depressive disorder: A meta-analysis of head-to-head randomized clinical trials

OBJECTIVE

Agomelatine is a new antidepressant with unique melatonin receptor type 1A (MTNR1A) and 1B ( MTNR1B) agonism and serotonergic receptor 5-hydroxytryptamine receptor 2C (5-HT-2C) antagonism. Several studies of patients with major depressive disorder (MDD) have confirmed the superior efficacy and safety of agomelatine in comparison with established treatments, such as selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs). This meta-analysis comprehensively shows the efficacy, acceptability, and safety of agomelatine in comparison with SSRIs and SNRIs used as antidepressants in MDD.

METHOD

Comprehensive electronic database searches were performed to identify reports of head-to-head randomized controlled trials that have compared agomelatine with SSRIs or SNRIs in terms of efficacy/effectiveness in treating MDD. Response and remission rates at both acute (6-12 weeks) and follow-up (24 weeks) phases, Clinical Global Impression-Improvement Scale response and remission rates, changes in depression scale scores, improvements in subjective sleep, dropout rates, and side effect rates were extracted and analysed.

RESULTS

The meta-analysis included six head-to-head trials involving 1871 patients. In the acute phase, agomelatine had higher response rates (relative risk (RR) 1.08, 95% confidence interval (CI) 1.02-1.15) compared to SSRIs and SNRIs. In the remission analysis, only acute remission rates (RR 1.12, 95% CI 1.01-1.24) significantly differed. The action of agomelatine was superior on the Leeds Sleep Evaluation Questionnaire-Quality of Sleep score (mean difference 4.05, 95% CI 0.61-7.49). Discontinuation due to inefficacy did not differ between agomelatine and SSRIs/SNRIs (RR 0.74, 95% CI 0.42-1.28). Compared to SSRIs and SNRIs, however, agomelatine revealed a lower rate of discontinuation due to side effects (RR 0.38, 95% CI 0.25-0.57).

CONCLUSIONS

Agomelatine has significantly higher efficacy and potential acceptability compared to SSRIs and SNRIs when treating MDD. However, the difference in efficacy is not considered clinically relevant. Because of its unique chronobiotic effects, agomelatine may be useful for the management of some MDD patients with circadian disturbance.

Evidence-based pharmacological treatment of anxiety disorders, post-traumatic stress disorder and obsessive-compulsive disorder: a revision of the 2005 guidelines from the British Association for Psychopharmacology

This revision of the 2005 British Association for Psychopharmacology guidelines for the evidence-based pharmacological treatment of anxiety disorders provides an update on key steps in diagnosis and clinical management, including recognition, acute treatment, longer-term treatment, combination treatment, and further approaches for patients who have not responded to first-line interventions. A consensus meeting involving international experts in anxiety disorders reviewed the main subject areas and considered the strength of supporting evidence and its clinical implications. The guidelines are based on available evidence, were constructed after extensive feedback from participants, and are presented as recommendations to aid clinical decision-making in primary, secondary and tertiary medical care. They may also serve as a source of information for patients, their carers, and medicines management and formulary committees.

Paroxetine versus other anti-depressive agents for depression

BACKGROUND

Paroxetine is the most potent inhibitor of the reuptake of serotonin of all selective serotonin reuptake inhibitors (SSRIs) and has been studied in many randomised controlled trials (RCTs). However, these comparative studies provided contrasting findings and systematic reviews of RCTs have always considered the SSRIs as a group, and evidence applicable to this group of drugs might not be applicable to paroxetine alone. The present systematic review assessed the efficacy and tolerability profile of paroxetine in comparison with tricyclics (TCAs), SSRIs and newer or non-conventional agents.

OBJECTIVES

1. To determine the efficacy of paroxetine in comparison with other anti-depressive agents in alleviating the acute symptoms of Major Depressive Disorder.2. To review acceptability of treatment with paroxetine in comparison with other anti-depressive agents.3. To investigate the adverse effects of paroxetine in comparison with other anti-depressive agents.

SEARCH METHODS

We searched the Cochrane Depression, Anxiety and Neurosis Review Group's Specialized Register (CCDANCTR, to 30 September 2012), which includes relevant randomised controlled trials from the following bibliographic databases: The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). Reference lists of relevant papers and previous systematic reviews were handsearched. Pharmaceutical companies marketing paroxetine and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

All randomised controlled trials allocating participants with major depression to paroxetine versus any other antidepressants (ADs), both conventional (such as TCAs, SSRIs) and newer or non-conventional (such as hypericum). For trials which had a cross-over design, only results from the first randomisation period were considered.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked eligibility and extracted data using a standard form. Data were then entered in RevMan 5.2 with a double-entry procedure. Information extracted included study and participant characteristics, intervention details, settings and efficacy, acceptability and tolerability measures.

MAIN RESULTS

A total of 115 randomised controlled trials (26,134 participants) were included. In 54 studies paroxetine was compared with older ADs, in 21 studies with another SSRI, and in 40 studies with a newer or non-conventional antidepressant other than SSRIs. For the primary outcome (patients who responded to treatment), paroxetine was more effective than reboxetine at increasing patients who responded early to treatment (Odds Ratio (OR): 0.66, 95% Confidence Interval (CI) 0.50 to 0.87, number needed to treat to provide benefit (NNTb) = 16, 95% CI 10 to 50, at one to four weeks, 3 RCTs, 1375 participants, moderate quality of evidence), and less effective than mirtazapine (OR: 2.39, 95% CI 1.42 to 4.02, NNTb = 8, 95% CI 5 to 14, at one to four weeks, 3 RCTs, 726 participants, moderate quality of evidence). Paroxetine was less effective than citalopram in improving response to treatment (OR: 1.54, 95% CI 1.04 to 2.28, NNTb = 9, 95% CI 5 to 102, at six to 12 weeks, 1 RCT, 406 participants, moderate quality of evidence). We found no clear evidence that paroxetine was more or less effective compared with other antidepressants at increasing response to treatment at acute (six to 12 weeks), early (one to four weeks), or longer term follow-up (four to six months). Paroxetine was associated with a lower rate of adverse events than amitriptyline, imipramine and older ADs as a class, but was less well tolerated than agomelatine and hypericum. Included studies were generally at unclear or high risk of bias due to poor reporting of allocation concealment and blinding of outcome assessment, and incomplete reporting of outcomes.

AUTHORS' CONCLUSIONS

Some possibly clinically meaningful differences between paroxetine and other ADs exist, but no definitive conclusions can be drawn from these findings. In terms of response, there was a moderate quality of evidence that citalopram was better than paroxetine in the acute phase (six to 12 weeks), although only one study contributed data. In terms of early response to treatment (one to four weeks) there was moderate quality of evidence that mirtazapine was better than paroxetine and that paroxetine was better than reboxetine. However there was no clear evidence that paroxetine was better or worse compared with other antidepressants at increasing response to treatment at any time point. Even if some differences were identified, the findings from this review are better thought as hypothesis forming rather than hypothesis testing and it would be reassuring to see the conclusions replicated in future trials. Finally, most of included studies were at unclear or high risk of bias, and were sponsored by the drug industry. The potential for overestimation of treatment effect due to sponsorship bias should be borne in mind.

Comparable efficacy and safety of 8 weeks treatment with agomelatine 25-50mg or fluoxetine 20-40mg in Asian out-patients with major depressive disorder

OBJECTIVE

This randomized, double-blind study evaluates the efficacy and tolerability of agomelatine, using fluoxetine as an active comparator, in Asian patients suffering from moderate to severe major depressive disorder (MDD).

METHOD

Patients were randomly assigned to receive either agomelatine (25-50mg/day, n=314) or fluoxetine (20-40mg/day, n=314) during an 8-week treatment period. The main outcome measure was the change in Hamilton Depression Rating Scale 17 items (HAM-D17) scores. Secondary efficacy criteria included scores on Clinical Global Impression Severity of illness (CGI-S) and Improvement of illness (CGI-I), patient sleeping improvement using the self-rating Leeds Sleep Evaluation Questionnaire (LSEQ) and anxiety using the Hamilton Anxiety Rating Scale (HAM-A) scores. Tolerability and safety evaluations were based on emergent adverse events.

RESULTS

Agomelatine and fluoxetine exert a comparable antidepressant efficacy in the Asian population. Mean changes over 8 weeks were clinically relevant and similar in both groups (-14.8±7.3 and -15.0±8.1 on HAM-D17 scale in agomelatine and fluoxetine groups, respectively). The between-group difference reached statistical significance on non-inferiority test (p=0.015). Clinically relevant decreases in CGI-S and CGI-I scores were observed over the treatment period in both groups. The two treatments were equally effective on the symptoms of both anxiety and sleep. The good tolerability profile and safety of both doses of agomelatine was confirmed in the Asian population.

CONCLUSIONS

Agomelatine and fluoxetine are equally effective in the treatment of MDD-associated symptoms in Asian depressed patients.

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

OBJECTIVE

To systematically review published and unpublished efficacy studies of agomelatine in people with depression.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Literature search (Pubmed, Embase, Medline), Cochrane Central Register of Controlled Trials, European Medicines Agency (EMA) regulatory file for agomelatine, manufacturers of agomelatine (Servier).

ELIGIBILITY CRITERIA

Double blind randomised placebo and comparator controlled trials of agomelatine in depression with standard depression rating scales.

DATA SYNTHESIS

Studies were pooled by using a random effects model with DerSimonian and Laird weights for comparisons with placebo and comparator antidepressant. The primary efficacy measure (change in rating scale score) was summarised with standardised mean difference (SMD; a measure of effect size) and secondary outcome measures with relative risks. All results were presented with 95% confidence intervals. Statistical heterogeneity was explored by visual inspection of funnel plots and by the I(2) statistic. Moderators of effect were explored by meta-regression.

RESULTS

We identified 20 trials with 7460 participants meeting inclusion criteria (11 in the published literature, four from the European Medicines Agency file, and five from the manufacturer). Almost all studies used the 17 item Hamilton depression rating scale (score 0-50). Agomelatine was significantly more effective than placebo with an effect size (SMD) of 0.24 (95% confidence interval 0.12 to 0.35) and relative risk of response 1.25 (1.11 to 1.4). Compared with other antidepressants, agomelatine showed equal efficacy (SMD 0.00, -0.09 to 0.10). Significant heterogeneity was uncovered in most analyses, though risk of bias was low. Published studies were more likely than unpublished studies to have results that suggested advantages for agomelatine.

CONCLUSIONS

Agomelatine is an effective antidepressant with similar efficacy to standard antidepressants. Published trials generally had more favourable results than unpublished studies.

Could agomelatine be the ideal antidepressant?

Depressive disorders are a common cause of chronic and recurrent psychiatric dysfunction, constituting the fourth leading cause of global diseases. Depression is associated with a high rate of morbidity and mortality, and is a leading cause of global disability. Despite the effectiveness of most currently available antidepressants, many of them have a number of undesirable side effects. Agomelatine is the first melatonin (MT)(1)/MT(2) agonist having 5-hydroxytryptamine (5-HT)(2C) and 5-HT(2B) antagonist properties and antidepressant activity. Agomelatine is effective in several animal models of depression and anxiety. In addition, three large, multicenter, multinational, placebo-controlled studies and several double-blind, placebo-controlled trials of agomelatine have demonstrated that it is a clinically effective and well-tolerated antidepressant in acute trials. Since currently available antidepressants are not always adequate to cause complete remission of symptoms in severely depressed patients, the superior rate of response achieved with agomelatine in this group of patients underlines its future for clinical use in depressive disorders. In summary, the clinical advantage of agomelatine is attributed to its novel mechanism of action, which helps not only to exert antidepressant action, but also to regulate the sleep-wake rhythm.

Emerging treatments for major depression

Antidepressant drugs were introduced into clinical practice in the mid-20th Century. While for the most part they have proven effective for the amelioration of depressive symptoms, they are associated with significant deficiencies. These well-recognized shortcomings have given impetus to the pursuit of new molecules that seek to improve on the efficacy, tolerability and safety of existing medications. The following article reviews several new compounds that may have antidepressant potential. Some are more advanced in development, having undergone clinical trials, whereas the clinical potential of others is yet to be explored. For this latter group of compounds, the antidepressant potential relies on their activity in validated animal models. Agomelatine and duloxetine are in the first category, having shown antidepressant efficacy in clinical trials. The blockade of cortisol secretion continues to be a focus of attention for the development of new antidepressants. Thus, synthesis inhibitors, nonpeptide antagonists of corticotropin-releasing factor and glucocorticoid receptor antagonists show some promise in clinical and preclinical tests. Antagonists of the neuropeptide substance P, vasopressin and neuropeptide Y represent a departure of approach from traditional monoamine receptor-based mechanisms. While the clinical results with one substance P antagonist have led to the cessation of further trials, other molecules are in development. Approaches to treatment based on glutamatergic transmission arose from observations in animal models. The clinical evaluation of such compounds awaits further development. The extent to which new agents can be judged to have met the goals of efficacy, tolerability and safety rely not only acute treatment trials but also on longer-term outcomes and postmarketing surveillance. Whether any of the new agents canvassed here prove to be significantly better than existing agents is clearly a judgement for the future.

Agomelatine in the treatment of depressive disorders in clinical practice: multicenter observational CHRONOS study

BACKGROUND

CHRONOS was a large naturalistic study designed to evaluate the effectiveness and safety of agomelatine in the management of patients with major depression in routine clinical practice.

METHODS

Patients (n=6,276) with a moderate or severe major depressive episode without psychotic symptoms were treated initially as outpatients (80.2%) or in psychiatric facilities (19.8%) in 54 regions of the Russian Federation. Patients received a flexible-dosing regimen of agomelatine 25 mg or 50 mg once daily for 8 weeks, with frequent study visits (weeks 1, 2, 3, 4, 6, and 8).

RESULTS

Patients (mean age 44 years, 72.6% female) showed progressive improvement on the 17-item Hamilton Rating Scale for Depression (HAMD-17) total score from 22±6.9 at baseline to 4.7±4.7 at week 8 (P<0.0001). The proportion of responders (HAMD-17 decrease of ≥50%) was 90.1% and the proportion of remitters (HAMD-17 <7) was 79.1% at week 8. All individual HAMD-17 item scores improved rapidly, and the change relative to baseline was significant (P<0.0001) at week 1 and at each subsequent visit in all cases. There were corresponding rapid improvements in Clinical Global Impression Severity and Improvement scores. In the subgroup of patients with more severe illness (HAMD-17 ≥21 at baseline; n=3,478), the proportions of responders and remitters were 92.4% and 72.8%, respectively, at week 8.

CONCLUSION

Agomelatine was effective and well tolerated in a large sample of depressed patients in an observational treatment setting, and showed a rapid onset of benefit across all HAMD-17 items.

Agomelatine versus other antidepressive agents for major depression

BACKGROUND

Major depressive disorder (MDD), or depression, is a syndrome characterised by a number of behavioural, cognitive and emotional features. It is most commonly associated with a sad or depressed mood, a reduced capacity to feel pleasure, feelings of hopelessness, loss of energy, altered sleep patterns, weight fluctuations, difficulty in concentrating and suicidal ideation. There is a need for more effective and better tolerated antidepressants to combat this condition. Agomelatine was recently added to the list of available antidepressant drugs; it is a novel antidepressant that works on melatonergic (MT1 and MT2), 5-HT 2B and 5-HT2C receptors. Because the mechanism of action is claimed to be novel, it may provide a useful, alternative pharmacological strategy to existing antidepressant drugs.

OBJECTIVES

The objective of this review was 1) to determine the efficacy of agomelatine in alleviating acute symptoms of major depressive disorder in comparison with other antidepressants, 2) to review the acceptability of agomelatine in comparison with other antidepressant drugs, and, 3) to investigate the adverse effects of agomelatine, including the general prevalence of side effects in adults.

SEARCH METHODS

We searched the Cochrane Collaboration's Depression, Anxiety and Neurosis Review Group's Specialised Register (CCDANCTR) to 31 July 2013. The CCDANCTR includes relevant randomised controlled trials from the following bibliographic databases: CENTRAL (the Cochrane Central Register of Controlled Trials) (all years), EMBASE (1974 onwards), MEDLINE (1950 onwards) and PsycINFO (1967 onwards). We checked reference lists of relevant studies together with reviews and regulatory agency reports. No restrictions on date, language or publication status were applied to the search. Servier Laboratories (developers of agomelatine) and other experts in the field were contacted for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating adult participants with major depression to agomelatine versus any other antidepressive agent.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and a double-entry procedure was employed. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy, acceptability and tolerability.

MAIN RESULTS

A total of 13 studies (4495 participants) were included in this review. Agomelatine was compared to selective serotonin reuptake inhibitors (SSRIs), namely paroxetine, fluoxetine, sertraline, escitalopram, and to the serotonin-norepinephrine reuptake inhibitor (SNRI), venlafaxine. Participants were followed up for six to 12 weeks. Agomelatine did not show any advantage or disadvantage over the other antidepressants for our primary outcome, response to treatment (risk ratio (RR) 1.01, 95% confidence interval (CI) 0.95 to 1.08, P value 0.75 compared to SSRIs, and RR 1.06; 95% CI 0.98 to 1.16, P value 0.16 compared to venlafaxine). Also, agomelatine showed no advantage or disadvantage over other antidepressants for remission (RR 0.83; 95% CI 0.68 to 1.01, P value 0.07 compared to SSRIs, and RR 1.08; 95% CI 0.94 to 1.24, P value 0.73 compared to venlafaxine). Overall, agomelatine appeared to be better tolerated than venlafaxine in terms of lower rates of drop outs (RR 0.40; 95% CI 0.24 to 0.67, P value 0.0005), and showed the same level of tolerability as SSRIs (RR 0.95; 95% CI 0.83 to 1.09, P value 0.44). Agomelatine induced a lower rate of dizziness than venlafaxine (RR 0.19, 95% CI 0.06 to 0.64, P value 0.007).With regard to the quality of the body of evidence, there was a moderate risk of bias for all outcomes, due to the number of included unpublished studies. There was some heterogeneity, particularly between published and unpublished studies. The included studies were conducted in inpatient and outpatient settings, thus limiting the generalisability of the results to primary care settings. With regard to precision, the efficacy outcomes were precise, but the tolerability outcomes were mostly imprecise. Publication bias was variable and depended on the outcome of the trial. Our review included unpublished studies, and we think that this reduced the impact of publication bias. The overall methodological quality of the studies was not very good. Almost all of the studies were sponsored by the pharmaceutical company that manufactures agomelatine (Servier), and some of these were unpublished. Attempts to contact the pharmaceutical company Servier for additional information on all unpublished studies were unsuccessful.

AUTHORS' CONCLUSIONS

Agomelatine did not seem to provide a significant advantage in efficacy over other antidepressive agents for the acute-phase treatment of major depression. Agomelatine was better tolerated than paroxetine and venlafaxine in terms of overall side effects, and fewer participants treated with agomelatine dropped out of the trials due to side effects compared to sertraline and venlafaxine, but data were limited because the number of included studies was small. We found evidence that compared agomelatine with only a small number of other active antidepressive agents, and there were only a few trials for each comparison, which limits the generalisability of the results. Moreover, the overall methodological quality of the studies was low, and, therefore, no firm conclusions can be drawn concerning the efficacy and tolerability of agomelatine.