Agomelatine-induced hepatotoxicity

Non-Adherence to Antidepressant Treatment and Related Factors in a Region of Spain: A Population-Based Registry Study

Antidepressants are a commonly prescribed psychotropic medication, and their use has increased in recent years. Medication non-adherence in patients with mental disorders is associated with worse health outcomes. A population-based registry study to assess antidepressant non-adherence during 2021 has been carried out. An indirect method based on the medication possession ratio (MPR) has been utilized. Patients with a MPR under 80% were classified as non-adherent. A multivariate logistic regression to identify non-adherence predictors has been used, considering sociodemographic (age, sex, institutionalization and urbanicity) and health related variables (diagnostics, antidepressant class, multiple prescribers, and polypharmacy). In 2021, 10.6% of the Castile and Leon population used antidepressants. These patients were institutionalized (7.29%), living in urban areas (63.44%), polymedicated with multiple prescribers (57.07%), and using serotonin selective reuptake inhibitors (SSRIs) (54.77%), other antidepressants (46.82%) or tricyclic antidepressants (TCAs) (13.76%). Antidepressants were prescribed mainly for depression (36.73%) and anxiety (29.24%). Non-adherence to antidepressants was more frequent in men (20.56%) than in woman (19.59%) and decreased with increasing age (32% up to 17 years old vs. 13.76% over 80 years old). TCAs were associated with the highest prevalence of non-adherence (23.99%), followed by SSRIs (20.19%) and other antidepressants (18.5%). Predictors of non-adherence in patients on antidepressants were: living in urban areas, using TCAs, and pain occurrence. Non-adherence to antidepressants decreases with aging. Being female, institutionalization, being polymedicated and having depression/anxiety alongside another psychiatric diagnosis are protective factors against non-adherence. The MPR is a robust indicator for the clinician to identify non-adherent patients for monitoring, and adopt any necessary corrective actions.

Novel pharmacological treatments for generalized anxiety disorder: Pediatric considerations

BACKGROUND

Pediatric anxiety disorders such as generalized anxiety disorder (GAD) are common, impairing, and often undertreated. Moreover, many youth do not respond to standard, evidence-based psychosocial or psychopharmacologic treatment. An increased understanding of the gamma-aminobutyric acid (GABA) and glutamate neurotransmitter systems has created opportunities for novel intervention development for pediatric GAD.

METHODS

This narrative review examines potential candidates for pediatric GAD: eszopiclone, riluzole, eglumegad (LY354740), pimavanserin, agomelatine.

RESULTS

The pharmacology, preclinical data, clinical trial findings and known side effects of eszopiclone, riluzole, eglumegad (LY354740), pimavanserin, agomelatine, are reviewed, particularly with regard to their potential therapeutic relevance to pediatric GAD.

CONCLUSION

Notwithstanding numerous challenges, some of these agents represent potential candidate drugs for pediatric GAD. Further treatment development studies of agomelatine, eszopiclone, pimavanserin and riluzole for pediatric GAD also have the prospect of informing the understanding of GABAergic and glutamatergic function across development.

Effects of agomelatine on pentylenetetrazole-induced kindling, kindling-associated oxidative stress, and behavioral despair in mice and modulation of its actions by luzindole and 1-(m-chlorophenyl) piperazine

In view of well-evidenced antiepileptic effects of melatonin and few reports of anticonvulsant action of agomelatine, the present study investigated whether agomelatine protects against pentylenetetrazole (PTZ)-induced kindling in mice and kindling-associated oxidative stress, depression, and impairment of spatial memory. In order to explore whether effects are mediated by melatonergic or serotonergic mechanisms, 1-(m-chlorophenyl) piperazine (mCPP), selective 5HT2c receptor agonist and luzindole, melatonergic receptor antagonist, were taken as pharmacological tools. In view of few hepatotoxic reports on agomelatine, the study evaluated effects on hepatic enzyme levels. Swiss strain albino mice were injected with PTZ (25mg/kg, i.p.) once every two days for 5weeks to induce kindling. The effects of agomelatine (10mg/kg, p.o.) alone and in combination with luzindole (2.5mg/kg, i.p.) or mCPP (7mg/kg, i.p.) on seizure severity during induction and % incidence of animals kindled at the end of 5weeks were recorded. Modified forced swim test was used for studying depression-like behavior while spontaneous alternation behavior was used for studying effects on spatial memory. Serum AST and ALT concentrations, cortical and hippocampal malondialdehyde, and reduced glutathione were measured. Agomelatine 10mg/kg, p.o. effectively delayed development of kindling, reduced seizure severity, and decreased % incidence. Luzindole reversed the protective effects of agomelatine while mCPP failed to show such a reversal, indicating melatonergic (and not serotonergic) mechanisms in the observed effects. Agomelatine also showed antioxidant effects that can partially contribute to its anticonvulsant action. In addition, it alleviated PTZ-kindling-associated behavioral despair and favorably modulated liver enzymes. Its effects on improvement of kindling-associated spatial memory could possibly be related to its effects on locomotor activity. Agomelatine, thus, could be explored as an adjunct to antiepileptic drugs for seizure control and for alleviating epilepsy-associated depression.

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.

Moclobemide as add-on therapy to agomelatine in a patient with treatment-resistant major depressive disorder: a psychopharmacological case

OBJECTIVE

Treatment-resistant depression is a major depressive disorder that does not respond to adequate treatment of at least two antidepressants and is one of the major clinical challenges for clinicians and clinical pharmacists. One treatment option is to switch the patient to a different medication. Another option is to add a medication to the patient's current pharmacotherapy. This article presents an improvement of symptoms induced by a combination of moclobemide (MOC) and agomelatine (AG) treatment in a 48-year-old Caucasian woman with treatment-resistant major depressive disorder (MDD). The patient had been treated with numerous antidepressants in the last 2 years that had not been effective or had caused serious adverse effects. When MOC 300 mg daily was added to AG 25 mg daily, the patient recovered progressively without any adverse effects. Her functional status also appeared stable. No other drugs known to interact with AG were administered. The MOC dose was subsequently increased to 600 mg daily and was taken with AG 25 mg daily and zolpidem 5 mg daily.

DISCUSSION

The positive effects of AG or MOC on MDD have been widely reported, but there have not been reports of a combined treatment with MOG and AG improving symptoms of treatment-resistant MDD. The exact mechanism of this effect on the central nervous system is unknown. The additive activity could have been caused by a broader spectrum activity of AG and MOC.

CONCLUSION

In this report, we identified a case with positive evidence of this antidepressant combination relieving the symptoms of treatment-resistant MDD, which is otherwise difficult to manage. This case report may serve to help clinicians and clinical pharmacists as a new treatment option for treatment-resistant MDD, although further research is needed to confirm this practice.

A systematic review of agomelatine-induced liver injury

Agomelatine is an antidepressant with a unique mechanism of action. Since its marketing in 2009, concerns have been raised regarding its potential to induce liver injury. The authors therefore address the need to comprehensively evaluate the potential risk posed by agomelatine of inducing liver injury by reviewing data from published and unpublished clinical trials in both the pre- and postmarketing settings, as well as data from non-interventional studies, pharmacovigilance database reviews and one case report. Recommendations for clinicians are also provided.

In this review, agomelatine was found to be associated with higher rates of liver injury than both placebo and the four active comparator antidepressants used in the clinical trials for agomelatine, with rates as high as 4.6% for agomelatine compared to 2.1% for placebo, 1.4% for escitalopram, 0.6% for paroxetine, 0.4% for fluoxetine, and 0% for sertraline. The review also provides evidence for the existence of a positive relationship between agomelatine dose and liver injury. Furthermore, rates of liver injury were found to be lower in non-interventional studies. Findings from pharmacovigilance database reviews and one case report also highlight the risk of agomelatine-induced liver injury.

As agomelatine does pose a risk of liver injury, clinicians must carefully monitor liver function throughout treatment. However, agomelatine’s unique mechanism of action and favourable safety profile render it a valuable treatment option.

A quantitative analysis of agomelatine-induced liver injury is lacking in the literature and would be welcomed.

Agomelatine-induced liver injury in a patient with choledocholithiasis

OBJECTIVE

A case of agomelatine-induced hepatotoxicity is described in a 47-year female patient who has received the drug, 25 mg/day, for 4 months, for the treatment of depression.

METHODS

The patient was admitted to the Department of Gastroenterology because of fatigue and nausea, with concomitant elevation of alanine aminotransferase (ALT), 550 U/L, and asparagine aminotransferase (AST), 300 U/L.

RESULTS

Liver biopsy showed diffuse lymphocyte infiltration in the dilated portal spaces without lesion of hepatic lobules. Several weeks after stopping agomelatine, the liver enzymes returned to normal. Subsequently, small gallstones in common bile duct were detected and removed by the endoscopic sphincterotomy.

CONCLUSIONS

It is hypothesized that choledocholithiasis could theoretically increase a risk of developing agomelatine-induced hepatotoxicity in this patient. Any pre-existing liver disease should be a contraindication for treatment with agomelatine.

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.

Pharmacokinetic evaluation of agomelatine for the treatment of generalised anxiety disorder

INTRODUCTION

Preliminary data indicate agomelatine as a promising molecule for both acute and long-term treatment of generalised anxiety disorder (GAD).

AREAS COVERED

The present review illustrates the pharmacokinetic properties of agomelatine and their implications for the management of GAD patients. A search of the main database sources (Medline, Isi Web of Knowledge and Medscape) was performed in order to obtain a complete and balanced evaluation of agomelatine pharmacokinetics for the treatment of GAD. The word 'agomelatine' was associated with 'pharmacokinetics', 'GAD', 'anxiety' and 'tolerability'. No restriction criteria were established in relation to methodology or year of publication. Only English-language articles were included.

EXPERT OPINION

Short half-life and 1-day administration make agomelatine an interesting molecule for GAD treatment. However, potential interactions with a number of compounds necessitate caution when prescribing and using agomelatine in patients with psychiatric (e.g., alcohol abuse) or medical comorbidities. Further data are necessary to define a precise risk/benefit ratio in special populations such as elderly patients suffering from GAD.

Synthesis and evaluation of amide side-chain modified Agomelatine analogues as potential antidepressant-like agents

In this work, nineteen analogues of Agomelatine were readily synthesized through structural modification of the acetamide side-chain starting from the key common intermediate 2-(7-methoxynaphthalen-1-yl) ethanamine (3), which was prepared from commercially available compound 2-(7-methoxynaphthalen-1-yl) acetonitrile (2) in two steps. Corticosterone-induced PC12 pheochromocytoma cells phenotypic in vitro model was utilized to evaluate their potential antidepression activities. Imide compound 4a and acylamino carboxylic acid analogue 5b showed good protective effects on traumatic PC12 cells with protection rates of 34.2% and 23.2%, respectively. Further in vivo assessments in C57 mice FST (forced swim test) model demonstrated that compound 4a significantly reduced the immobility time of the tested subjects, indicating antidepressant-like activity. Preliminary toxicity assays conducted on human normal liver L02 cells and embryonic kidney 293 cells suggested a relatively low safety risk for compound 4a compared with the marketed drugs Agomelatine and Fluoxetine. The promising antidepressant-like efficacy of compound 4a, together with the relatively low toxicity to the normal tested cells and high liability of diffusion through the blood-brain barrier (BBB), presents us insights of exploration of me-better drug candidates of Agomelatine.