Clinical utility of vilazodone for the treatment of adults with major depressive disorder and theoretical implications for future clinical use

The role of new antidepressants in clinical practice in Canada: a brief review of vortioxetine, levomilnacipran ER, and vilazodone

Although many branded and generic antidepressants are approved for the treatment of major depressive disorder (MDD) in Canada, efficacy and tolerability differ among patients, and new treatment options are needed. Symptom types (eg, fatigue, energy/motivation, cognition, and functioning), medication type, treatment duration, and the need for maintenance therapy are factors that may influence treatment effectiveness. Three antidepressants, vortioxetine, levomilnacipran extended-release (ER), and vilazodone have recently become available in Canada. The aim of this review is to contextualize differences in their mechanistic and clinical profiles, thereby providing practitioners with knowledge to support treatment decisions. In trials versus placebo, each drug improved depressive symptoms in adult patients with MDD. The antidepressant effect of vortioxetine may be related to enhanced serotonergic activity via reuptake inhibition and agonism and/or antagonism of various serotonin receptors. Vortioxetine may also improve cognitive functioning in MDD, and has proven efficacious in relapse prevention. Nausea was the most commonly reported adverse event (AE); rates of sexual dysfunction were low and abrupt discontinuation was well tolerated. Levomilnacipran ER, a serotonin norepinephrine reuptake inhibitor, demonstrated greater improvement versus placebo in functional impairment as well as depressive symptoms; in post hoc analyses, improvement in symptoms of motivation and energy were observed. Nausea was the most commonly reported AE; gradual discontinuation is recommended to avoid discontinuation syndrome. Vilazodone is a serotonin reuptake inhibitor and partial serotonergic 5-HT1A receptor agonist. In addition to improvement in depressive symptoms, evidence suggests that vilazodone may be particularly well suited for depressed patients with high anxiety levels. Diarrhea, nausea, and headache were the most common AEs; low rates of sexual dysfunction were reported. The 2016 Canadian Network for Mood and Anxiety Treatments guidelines for MDD includes vortioxetine as a first-line treatment; levomilnacipran ER and vilazodone are considered as second-line treatments due to lack of relapse prevention data at the time of approval.

Crystal structure of vilazodone hydro-chloride methanol monosolvate

In the title compound, C26H28N5O2+·Cl-·CH3OH {systematic name: 4-(2-carbamoyl-1-benzo-furan-5-yl)-1-[4-(5-cyano-1H-indol-3-yl)but-yl]piperazin-1-ium chloride methanol monosolvate}, the protonated piperazine ring adopts a chair conformation. The indole ring plane is nearly perpendicular to the benzo-furan ring system, with a dihedral angle of 85.77 (2)°. In the crystal, the organic cations, Cl- anions and methanol solvent mol-ecules are linked by classical N-H⋯O and N-H⋯Cl hydrogen bonds, and weak C-H⋯O and C-H⋯π inter-actions into a three-dimensional supra-molecular architecture.

The Preclinical and Clinical Effects of Vilazodone for the Treatment of Major Depressive Disorder

INTRODUCTION

Major depressive disorder (MDD) is the leading cause of disability worldwide, and according to the STAR*D trial, only 33% of patients with MDD responded to initial drug therapy. Augmentation of the leading class of antidepressant treatment, selective serotonin reuptake inhibitors (SSRIs), with the 5-HT1A receptor agonist buspirone has been shown to be effective in treating patients that do not respond to initial SSRI therapy. This suggests that newer treatments may improve the clinical picture of MDD. The US Food and Drug Administration (FDA) approved the antidepressant drug vilazodone (EMD 68843), a novel SSRI and 5-HT1A receptor partial agonist. Vilazodone has a half-life between 20-24 hours, reaches peak plasma concentrations at 3.7-5.3 hours, and is primarily metabolized by the hepatic CYP450 3A4 enzyme system.

AREAS COVERED

The authors review the preclinical and clinical profile of vilazodone. The roles of serotonin, the 5-HT1A receptor, and current pharmacotherapy approaches for MDD are briefly reviewed. Next, the preclinical pharmacological, behavioral, and physiological effects of vilazodone are presented, followed by the pharmacokinetic properties and metabolism of vilazodone in humans. Last, a brief summary of the main efficacy, safety, and tolerability outcomes of clinical trials of vilazodone is provided.

EXPERT OPINION

Vilazodone has shown efficacy versus placebo in improving depression symptoms in several double-blind, placebo-controlled trials. The long-term safety and tolerability of vilazodone treatment has also been established. Further studies are needed that directly compare patients treated with an SSRI (both with and without an adjunctive 5-HT1A partial agonist) versus patients treated with vilaozodone.

Major depressive disorder: mechanism-based prescribing for personalized medicine

Individual patients with depression present with unique symptom clusters - before, during, and even after treatment. The prevalence of persistent, unresolved symptoms and their contribution to patient functioning and disease progression emphasize the importance of finding the right treatment choice at the onset and the utility of switching medications based on suboptimal responses. Our primary goal as clinicians is to improve patient function and quality of life. In fact, feelings of well-being and the return to premorbid levels of functioning are frequently rated by patients as being more important than symptom relief. However, functional improvements often lag behind resolution of mood, attributed in large part to persistent and functionally impairing symptoms - namely, fatigue, sleep/wake disturbance, and cognitive dysfunction. Thus, patient outcomes can be optimized by deconstructing each patient's depressive profile to its component symptoms and specifically targeting those domains that differentially limit patient function. This article will provide an evidence-based framework within which clinicians may tailor pharmacotherapy to patient symptomatology for improved treatment outcomes.

8-hydroxy-2-(di-n-propylamino)tetralin intervenes with neural cell apoptosis following diffuse axonal injury

Previous studies have reported a neuroprotective effect of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) against traumatic brain injury. In accordance with the Marmarou method, rat models of diffuse axonal injury were established. 8-OH-DPAT was intraperitoneally injected into model rats. 8-OH-DPAT treated rats maintained at constant temperature served as normal temperature controls. TUNEL results revealed that neural cell swelling, brain tissue necrosis and cell apoptosis occurred around the injured tissue. Moreover, the number of Bax-, Bcl-2- and caspase-3-positive cells increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. However, brain injury was attenuated, the number of apoptotic cells reduced, Bax and caspase-3 expression decreased, and Bcl-2 expression increased at 6, 12, 24, 72 and 168 hours after diffuse axonal injury in normal temperature control and in 8-OH-DPAT-intervention rats. The difference was most significant at 24 hours. All indices in 8-OH-DPAT-intervention rats were better than those in the constant temperature group. These results suggest that 8-OH-DPAT inhibits Bax and caspase-3 expression, increases Bcl-2 expression, and reduces neural cell apoptosis, resulting in neuroprotection against diffuse axonal injury. This effect is associated with a decrease in brain temperature.

Multi-modality: a new approach for the treatment of major depressive disorder

Effective treatment with antidepressants is currently limited by factors that affect treatment compliance, including delay in onset of therapeutic effects and intolerable side-effects. Recent data suggest that use of antidepressant combinations with different mechanisms of action may be a better first-line strategy prior to augmentation with other drug classes. The rationale for this approach is that combining multiple pharmacological actions affecting multiple monoamine targets produces greater efficacy. Several new multi-modal compounds are in development and early results for the most advanced agents indicate shorter onset of therapeutic effects and improved tolerability. By modulating multiple receptors and transmitter systems, it is hoped that these new agents may also treat some of the associated symptoms of major depressive disorder, such as anxiety and cognitive dysfunction.