The use of agomelatine in OCD: effects on the motivational aspects and dysregulated circadian rhythms

Potential biomarkers and therapeutic targets for obsessive compulsive disorder: Evidences from clinical studies

Obsessive compulsive disorder (OCD) is a prevalent behavioral disorder with a complex etiology. However, the underlying pathogenic molecular pathways and the associated risk factors are largely obscure. This has hindered both the identification of relevant prognostic biomarkers and the development of effective treatment strategies. Because of the diverse range of clinical manifestations, not all patients benefit from therapies currently practiced in the clinical setting. Nevertheless, several lines of evidence indicate that neurotrophic, neurotransmitter, and oxidative signaling are involved in the pathophysiology of OCD. Based upon evidences from clinical (and pre-clinical studies), the present review paper sets out to decipher the utilities of three parameters (i.e. brain-derived neurotrophic factor; BDNF, noradrenalin-synthesizing enzyme dopamine beta-hydroxylase; DBH; and oxidative damage marker malondialdehyde; MDA) as diagnostic peripheral biomarkers as well as bio-targets for therapeutic strategies. While the data indicates promising results, there is necessitation for future studies to further confirm and establish these. Further, based again on the available clinical data, we investigated the possibilities of exploiting the etiological links between disruptions in the sleep-wake cycle and insulin signaling, and OCD for the identification of potential anti-OCD ameliorative agents with the ability to elicit multimodal effects, including attenuation of the alterations in BDNF, noradrenergic and redox pathways. In this respect, agomelatine and metformin may represent particularly interesting candidates; however, further clinical studies are warranted to establish these as singular or complementary medications in OCD subjects.

Agomelatine augmentation of sertraline in the treatment of moderate to severe obsessive-compulsive disorder: a randomized double-blinded placebo-controlled clinical trial

BACKGROUND

As 40-60% of the patients with obsessive-compulsive disorder (OCD) do not adequately respond to the first-line treatment, finding an effective second-line treatment is required. Our aim was to assess the efficacy and safety of agomelatine (a selective melatonin receptor agonist and a 5-hydroxytryptamine (HT)2 C antagonist) augmentation of sertraline in the treatment of patients with moderate to severe OCD.

METHODS

In this 12-week randomized, double-blinded, placebo-controlled, parallel-group clinical trial, 65 patients with moderate to severe OCD according to the Diagnostic and Statistical Manual of Mental Disorders-Fifth edition (DSM-5) criteria and a Yale-Brown obsessive compulsive scale (Y-BOCS) score of over 21, were included. They were assigned with sertraline (100 mg/day for the first 4 weeks and 200 mg/day for the next 8 weeks) and either agomelatine (25 mg/day) or placebo. The primary outcome was OCD symptoms measured by the Y-BOCS.

RESULTS

Fifty patients (24 in agomelatine group and 26 in placebo group) completed the trial. The Y-BOCS scores in total (MD (95% CI) = 12.25 (11.00, 13.49) (P < 0.001) vs. MD (95% CI) = 12.46 (6.65, 15.74) (P < 0.001)), the obsession subscale (MD (95% CI) = 5.04 (4.19, 5.88) (P < 0.001) vs. MD (95% CI) = 5.00 (3.84, 6.16) (P = 0.0001)), and compulsion subscale (MD (95% CI) = 7.21 (6.34, 8.07) (P < 0.001) vs. MD (95% CI) = 7.460 (6.50, 8.42) (P < 0.001)) significantly decreased in both groups. Although, at the end of the trial, no significant difference was observed between the scores of the two groups in total (MD (95% CI) = 0.480 (-1.23, 2.19) (P = 0.78)), the obsession subscale (MD (95% CI) = 1.020 (-0.15, 2.19) (P = 0.38)), and the compulsion subscale (MD (95% CI) = 0.540 (-0.34, 1.42) (P = 0.54)). No major adverse effects were recorded, and the frequency of side effects was not significantly different between the groups.

CONCLUSION

Agomelatine in augmentation with sertraline is safe and tolerable in patients with moderate to severe OCD. However, our study does not support its efficacy in improving OCD symptoms, compared to placebo.

TRIAL REGISTRATION

The trial was registered at the Iranian Registry of Clinical Trials on 14/07/2020 ( www.irct.ir ; IRCT ID: IRCT20170123032145N5).

The Psychopharmacology of Obsessive-Compulsive Disorder: A Preclinical Roadmap

This review evaluates current knowledge about obsessive-compulsive disorder (OCD), with the goal of providing a roadmap for future directions in research on the psychopharmacology of the disorder. It first addresses issues in the description and diagnosis of OCD, including the structure, measurement, and appropriate description of the disorder and issues of differential diagnosis. Current pharmacotherapies for OCD are then reviewed, including monotherapy with serotonin reuptake inhibitors and augmentation with antipsychotic medication and with psychologic treatment. Neuromodulatory therapies for OCD are also described, including psychosurgery, deep brain stimulation, and noninvasive brain stimulation. Psychotherapies for OCD are then reviewed, focusing on behavior therapy, including exposure and response prevention and cognitive therapy, and the efficacy of these interventions is discussed, touching on issues such as the timing of sessions, the adjunctive role of pharmacotherapy, and the underlying mechanisms. Next, current research on the neurobiology of OCD is examined, including work probing the role of various neurotransmitters and other endogenous processes and etiology as clues to the neurobiological fault that may underlie OCD. A new perspective on preclinical research is advanced, using the Research Domain Criteria to propose an adaptationist viewpoint that regards OCD as the dysfunction of a normal motivational system. A systems-design approach introduces the security motivation system (SMS) theory of OCD as a framework for research. Finally, a new perspective on psychopharmacological research for OCD is advanced, exploring three approaches: boosting infrastructure facilities of the brain, facilitating psychotherapeutic relearning, and targeting specific pathways of the SMS network to fix deficient SMS shut-down processes. SIGNIFICANCE STATEMENT: A significant proportion of patients with obsessive-compulsive disorder (OCD) do not achieve remission with current treatments, indicating the need for innovations in psychopharmacology for the disorder. OCD may be conceptualized as the dysfunction of a normal, special motivation system that evolved to manage the prospect of potential danger. This perspective, together with a wide-ranging review of the literature, suggests novel directions for psychopharmacological research, including boosting support systems of the brain, facilitating relearning that occurs in psychotherapy, and targeting specific pathways in the brain that provide deficient stopping processes in OCD.

Sleep, Circadian Rhythms, and Anxious Traits

Anxiety is adaptive and plays an important role in keeping us safe. However, when anxiety becomes too extreme, it can cause significant disruptions and distress. Understanding the mechanisms underlying excessive anxiety and how to best treat it is a priority for researchers and clinicians. There is increasing recognition that disruptions in the amount and timing of sleep are associated with anxiety symptoms and characteristics. In the current paper, we explore the intersections between sleep, circadian rhythms, and anxiety. First, we review accumulating evidence that anxiety is associated with disruptions in sleep and circadian rhythms in both clinical and nonclinical samples and across ages. Next, we discuss the data linking sleep disruptions with anxiety-related traits (anxiety sensitivity, neuroticism, and perfectionism) and patterns of cognition and emotion. Finally, potential treatment implications are highlighted. Overall, these data suggest that delineating the role of disruptions in the amount and timing of sleep holds promise for improving the lives of individuals with heightened anxiety.