A review of the clinical efficacy, safety and tolerability of the antidepressants vilazodone, levomilnacipran and vortioxetine

Switching to Vortioxetine in Patients with Poorly Tolerated Antidepressant-Related Sexual Dysfunction in Clinical Practice: A 3-Month Prospective Real-Life Study

Treatment-emergent sexual dysfunction (TESD) is one of the most frequent and persistent adverse effects of antidepressant medication. Sexual dysfunction (SD) secondary to SSRIs occurs in >60% of sexually active patients and >80% of healthy volunteers, with this causing treatment discontinuation in >35% of patients. However, this factor is rarely addressed in routine examinations, and only 15-30% of these events are spontaneously reported. A strategy of switching to a different non-serotonergic antidepressant could involve a risk of relapse or clinical worsening due to a lack of serotonergic activity. Vortioxetine appears to have less impact on sexual function due to its multimodal mechanism of action. No studies have been published on the effectiveness of switching to vortioxetine in patients with poorly tolerated long-term antidepressant-related SD in naturalistic settings.

STUDY OBJECTIVES

To determine the effectiveness of switching to vortioxetine due to SD in a routine clinical practice setting.

METHODOLOGY

observational pragmatic and naturalistic study to determine the effectiveness of the switch to vortioxetine (mean dosage 13.11 ± 4.03) in 74 patients aged 43.1 ± 12.65 (54% males) at risk of discontinuing treatment due to sexual dysfunction. The PRSexDQ*- SALSEX scale (* Psychotropic-Related Sexual Dysfunction Questionnaire) was applied at two moments: baseline visit and after 3 months of follow-up.

RESULTS

global Sexual Dysfunction (SD) measured with the SALSEX scale decreased significantly between the baseline visit (10.32; SD 2.73) and the follow-up visit (3.78; SD 3.68), p < 0.001. There was a significant improvement (p < 0.001) at the endpoint including decreased libido, delay of orgasm, anorgasmia and arousal difficulties in both sexes. After switching to vortioxetine, 83.81% of patients experienced an improvement in sexual function (43.2% felt greatly improved). Most patients (83.3%) who switched to vortioxetine continued treatment after the follow-up visit. A total of 58.1% of patients showed an improvement in depressive symptoms from the baseline visit.

CONCLUSION

switching to vortioxetine is an effective and reliable strategy to treat patients with poorly tolerated previous antidepressant-related sexual dysfunction in real-life clinical settings.

Adverse effects of 21 antidepressants on sleep during acute-phase treatment in major depressive disorder: a systemic review and dose-effect network meta-analysis

STUDY OBJECTIVES

Sleep-related adverse effects during acute treatment with antidepressants undermine adherence and impede remission. We aimed to address subtypes of sleep-related adverse effects and depict the relationship between dose and sleep-related adverse events.

METHODS

We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science for double-blind randomized controlled trials of depression published before April 30th, 2023. Eligible studies reporting sleep-related adverse effects during short-term monotherapy were included. The odds ratios (ORs) for sleep-related adverse effects were addressed with network meta-analysis. A Bayesian approach was used to depict the dose-effect relationship. Heterogeneity among studies was assessed using the τ2 and I2 statistics. Sensitivity analyses were performed without studies featuring high risk of bias.

RESULTS

Studies with 64 696 patients were examined from 216 trials. Compared to placebo, 13 antidepressants showed higher ORs for somnolence, of which fluvoxamine (OR = 6.32; 95% CI: 3.56 to 11.21) ranked the top. Eleven had higher risks for insomnia, reboxetine ranked the top (OR = 3.47; 95% CI: 2.77 to 4.36). The dose-effect relationships curves between somnolence or insomnia and dose included linear shape, inverted U-shape, and other shapes. There was no significant heterogeneity among individual studies. The quality of evidence for results in network meta-analyses was rated as very low to moderate by Grading of Recommendations Assessment, Development, and Evaluation.

CONCLUSIONS

Most antidepressants had higher risks for insomnia or somnolence than placebo. The diverse relationship curves between somnolence or insomnia and dose of antidepressants can guide clinicians to adjust the doses. These findings suggest clinicians pay more attention to sleep-related adverse effects during acute treatment with antidepressants.

A phase 3, multicenter, double-blind, randomized, placebo-controlled clinical trial to verify the efficacy and safety of ansofaxine (LY03005) for major depressive disorder

Major depressive disorder (MDD) is the most prevalent form of depression and is becoming a great challenge for public health and medical practice. Although first-line antidepressants offer therapeutic benefits, about 35% of depressed patients are not adequately treated, creating a substantial unmet medical need. A multicenter, double-blind, randomized, placebo-controlled phase 3 clinical trial was conducted in patients with MDD in China to assess the efficacy and safety of ansofaxine (LY03005), a potential triple reuptake inhibitor of serotonin, norepinephrine, and dopamine. Eligible 588 MDD patients were included and randomly assigned (1:1:1) to 8-week treatment with ansofaxine 80 mg/day(n = 187), ansofaxine 160 mg/day(n = 186), or placebo(n = 185). The primary efficacy endpoint was the Montgomery-Åsberg Depression Rating Scale (MADRS) total score change from baseline to the end of the study. Safety indexes included adverse events, vital signs, physical examination, laboratory tests, 12-lead electrocardiogram (ECG), and evaluation of suicide tendency and sexual function. Significant differences were found in mean changes in MADRS total score at week 8 in the two ansofaxine groups (80 mg, -20.0; 160 mg, -19.9) vs. placebo (-14.6; p < 0.0001). All doses of ansofaxine were generally well-tolerated. Treatment-emergent adverse events (TEAEs) were reported by 137 (74.46%) patients in ansofaxine 80 mg group, 144 (78.26%) patients in ansofaxine 160 mg and 125 (67.93%) patients in the placebo group. The incidence of treatment-related adverse events (TRAEs) was 59.2% (109 patients), 65.22% (120 patients) in the 80, 160 mg ansofaxine groups, and 45.11% (83 patients) in the placebo group. The initial results of this trial indicate that ansofaxine at both the 80 mg/day and 160 mg/day was effective and safe in adult patients with MDD. ClinicalTrials.gov Identifier: NCT04853407.

Psychological and Psychopharmacological Interventions in Psychocardiology

Patients with mental disorders have an increased risk to develop cardiovascular disease (CVD), and CVD are frequently comorbid with especially adjustment, anxiety and depressive disorders. Therefore, clinicians need to be aware of effective and safe psychological and pharmacological treatment strategies for patients with comorbid CVD and mental disorders. Cognitive behavioral therapy and third-wave of cognitive-behavioral therapy are effective for patients with CVD and mental disorders. Internet-based psychological treatments may also be considered. In more severe cases, psychopharmacological drugs are frequently used. Although generally well tolerated and efficacious, drug- and dose-dependent side effects require consideration. Among antidepressants, selective serotonin reuptake inhibitors, selective serotonin and noradrenalin reuptake inhibitors, and newer antidepressants, such as mirtazapine, bupropion, agomelatine, and vortioxetine, can be considered, while tricyclic antidepressants should be avoided due to their cardiac side effects. Mood stabilizers have been associated with arrhythmias, and some first- and second-generation antipsychotics can increase QTc and metabolic side effects, although substantial differences exist between drugs. Benzodiazepines are generally safe in patients with CVD when administered short-term, and may mitigate symptoms of acute coronary syndrome. Laboratory and ECG monitoring is always recommended in psychopharmacological drug-treated patients with CVD. Presence of a heart disease should not exclude patients from necessary interventions, but may require careful risk-benefit evaluations. Effectively and safely addressing mental disorders in patients with CVD helps to improve both conditions. Since CVD increase the risk for mental disorders and vice versa, care providers need to screen for these common comorbidities to comprehensively address the patients' needs.

Efficacy, Safety, and Tolerability of Ansofaxine (LY03005) Extended-Release Tablet for Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled, Dose-Finding, Phase 2 Clinical Trial

BACKGROUND

Ansofaxine (LY03005) extended-release tablet is a potential triple reuptake inhibitor of serotonin, norepinephrine, and dopamine. This study assessed the efficacy, safety, and appropriate dosage of ansofaxine for the treatment of major depressive disorder (MDD).

METHODS

A multicenter, randomized, double-blind, placebo-controlled, dose-finding, Phase 2 clinical trial was conducted in China. Eligible patients with MDD (18-65 years) were randomly assigned to receive fixed-dose ansofaxine extended-release tablets (40, 80, 120, or 160 mg/d) or placebo for 6 weeks. The primary outcome measure was a change in the total score on the 17-item Hamilton Depression Rating Scale from baseline to week 6.

RESULTS

A total of 260 patients were recruited from October 2015 to September 2017, and 255 patients received the study drug as follows: 40 mg (n = 52), 80 mg (n = 52), 120 mg (n = 51), and 160 mg (n = 51) ansofaxine and placebo (n = 49). Significant differences were found in mean changes in 17-item Hamilton Depression Rating Scale total scores at week 6 in the 4 ansofaxine groups vs placebo (-12.46; χ2 = -9.71, P = .0447). All doses of ansofaxine were generally well-tolerated. Treatment-related adverse events occurred in 141 patients (303 cases), yielding incidence rates of 51.92%, 65.38%, 56.86%, and 62.75% in the 40-, 80-, 120-, and 160-mg ansofaxine groups and 38.78% in the placebo group.

CONCLUSION

Active doses (40, 80, 120, and 160 mg/d) of ansofaxine in a controlled setting were safe, tolerated, and effective in improving depression symptoms in MDD patients.

Major depressive disorder: Validated treatments and future challenges

Depression is a prevalent psychiatric disorder that often leads to poor quality of life and impaired functioning. Treatment during the acute phase of a major depressive episode aims to help the patient reach a remission state and eventually return to their baseline level of functioning. Pharmacotherapy, especially selective serotonin reuptake inhibitors antidepressants, remains the most frequent option for treating depression during the acute phase, while other promising pharmacological options are still competing for the attention of practitioners. Depression-focused psychotherapy is the second most common option for helping patients overcome the acute phase, maintain remission, and prevent relapses. Electroconvulsive therapy is the most effective somatic therapy for depression in some specific situations; meanwhile, other methods have limits, and their specific indications are still being studied. Combining medications, psychotherapy, and somatic therapies remains the most effective way to manage resistant forms of depression.

5-HT Receptors and the Development of New Antidepressants

Serotonin modulates several physiological and cognitive pathways throughout the human body that affect emotions, memory, sleep, and thermal regulation. The complex nature of the serotonergic system and interactions with other neurochemical systems indicate that the development of depression may be mediated by various pathomechanisms, the common denominator of which is undoubtedly the disturbed transmission in central 5-HT synapses. Therefore, the deliberate pharmacological modulation of serotonergic transmission in the brain seems to be one of the most appropriate strategies for the search for new antidepressants. As discussed in this review, the serotonergic system offers great potential for the development of new antidepressant therapies based on the combination of SERT inhibition with different pharmacological activity towards the 5-HT system. The aim of this article is to summarize the search for new antidepressants in recent years, focusing primarily on the possibility of benefiting from interactions with various 5-HT receptors in the pharmacotherapy of depression.

Identification and characterization of forced degradation products of vortioxetine by LC/MS/MS and NMR

Vortioxetine (VTX) is a novel multimodal antidepressant drug that affects the serotoninergic and noradrenergic systems. In this work, the forced degradation of VTX was studied according to (ICH) Q1A (R2) guidelines. The study revealed that VTX was stable under thermal stress conditions and hydrolytic stress conditions i.e., acidic, basic and neutral conditions. In contrast, six degradation products (DPs) were formed under photolytic and oxidative stress conditions. The DPs were identified and characterized by high-resolution LC/MS and LC/MS/MS. The structures of major DPs were further confirmed by the synthesis and characterization by ¹H and ¹³C NMR data. A possible mechanism for the formation of the VTX DPs via photolytic/oxidative stress degradation pathway was proposed.

Analysis of Time-Course, Dose-Effect, and Influencing Factors of Antidepressants in the Treatment of Acute Adult Patients With Major Depression

OBJECTIVE

Model-based meta-analysis was used to describe the time-course and dose-effect relationships of antidepressants and also simultaneously investigate the impact of various factors on drug efficacy.

METHODS

This study is a reanalysis of a published network meta-analysis. Only placebo-controlled trials were included in this study. The change rate in depression rating scale scores from baseline was used as an efficacy indicator because a continuous variable is more likely to reflect subtle differences in efficacy between drugs.

RESULTS

A total 230 studies containing 64 346 patients were included in the analysis. The results showed that the number of study sites (single or multi-center) and the type of setting (inpatient or noninpatient) are important factors affecting the efficacy of antidepressants. After deducting the placebo effect, the maximum pure drug efficacy value of inpatients was 18.4% higher than that of noninpatients, and maximum pure drug efficacy value of single-center trials was 10.2% higher than that of multi-central trials. Amitriptyline showed the highest drug efficacy. The remaining 18 antidepressants were comparable or had little difference. Within the approved dose range, no significant dose-response relationship was observed. However, the time-course relationship is obvious for all antidepressants. In terms of safety, with the exception of amitriptyline, the dropout rate due to adverse events of other drugs was not more than 10% higher than that of the placebo group.

CONCLUSION

The number of study sites and the type of setting are significant impact factors for the efficacy of antidepressants. Except for amitriptyline, the other 18 antidepressants have little difference in efficacy and safety.

Kappa opioid receptor antagonism: Are opioids the answer for treatment resistant depression?

Introduction:

Past trials of buprenorphine (BUP) in the treatment of major depressive disorder (MDD) have displayed favorable results, although its clinical utility was limited by the risk of abuse or physical dependence. By combining BUP with samidorphan (SAM), the euphoric high is negated by an opposing mechanism, which theoretically reduces addictive-like properties while allowing the antidepressant properties to remain. As such, the objective of this article is to analyze the results of BUP/SAM premarketing clinical trials as adjunctive treatment for treatment-resistant MDD.

Methods:

A comprehensive PubMed/MEDLINE search was conducted through November 9, 2017, using the following search terms: depression, samidorphan, buprenorphine, ALKS-5461. Additional data were obtained from Clinicaltrials.gov and resources included in the present study. All English-language clinical trials evaluating the combination of BUP/SAM in the treatment of MDD were included.

Results:

A few premarketing studies have evaluated the efficacy and safety of BUP/SAM combination as adjunctive treatment in patients with treatment-resistant MDD. The FORWARD-1 through FORWARD-5 trials concluded (1) the most effective dosing ratio of BUP/SAM to reduce abuse potential was 1:1; (2) statistically significant changes in scores from baseline on the Montgomery-Asberg Depression Rating Scale were noted for the 2 mg/2 mg dose compared with placebo; and (3) the most commonly reported adverse effects were nausea, dizziness, and fatigue.

Discussion:

Buprenorphine/samidorphan has shown favorable results for efficacy and tolerability in premarketing studies evaluating its use as adjunctive therapy for treatment-resistant MDD. Its novel mechanism targeting the opioid pathway may serve as a promising antidepressant devoid of abuse potential.

Efficacy and safety of levomilnacipran, vilazodone and vortioxetine compared with other second-generation antidepressants for major depressive disorder in adults: A systematic review and network meta-analysis

BACKGROUND

Second-generation antidepressants dominate the medical management of major depressive disorder (MDD). Levomilnacipran, vilazodone and vortioxetine are the latest therapeutic options approved for the treatment of MDD. This systematic review aims to compare the benefits and harms of vilazodone, levomilnacipran, and vortioxetine with one another and other second-generation antidepressants.

METHODS

We searched electronic databases up to September 2017 and reviewed reference lists and pharmaceutical dossiers to detect published and unpublished studies. Two reviewers independently screened abstracts and full text articles, and rated the risk of bias of included studies. Randomized controlled trials (RCTs) and controlled observational studies including adult outpatients with MDD were eligible for inclusion. We conducted network meta-analyses on response to treatment using frequentist multivariate meta-analyses models. Placebo- and active-controlled trials were eligible for network meta-analyses.

RESULTS

Twenty-four studies met our inclusion criteria. Direct comparisons were limited to vilazodone versus citalopram, and vortioxetine versus duloxetine, paroxetine, or venlafaxine XR (extended release). Results of head-to-head trials and network meta-analyses, overall, indicated similar efficacy among levomilnacipran, vilazodone, or vortioxetine and other second-generation antidepressants. Although rates of overall adverse events and discontinuation due to adverse events were similar, RCTs reported several differences in specific adverse events. For most outcomes the strength of evidence was low.

LIMITATIONS

Limitations are the focus of literature searches on studies published in English, possible reporting biases, and general methodological limitations of network meta-analyses.

CONCLUSIONS

Overall, the available evidence does not indicate greater benefits or fewer harms of levomilnacipran, vilazodone, and vortioxetine compared with other second-generation antidepressants.

Assessment and management of sexual dysfunction in the context of depression

Sexual dysfunction (SD) is pervasive and underreported, and its effects on quality of life are underestimated. Due in part to its bidirectional relationship with depression, SD can be difficult to diagnose; it is also a common side effect of many antidepressants, leading to treatment noncompliance. While physicians often count on patients to spontaneously report SD, treatment is optimized when the clinician instead performs a thorough assessment of sexual functioning before and during drug therapy using a standardized questionnaire such as the Arizona Sexual Experiences Scale (ASEX). Separating the effects of the disorder from those of medications is challenging; we present a concise, evidence-based schematic to assist physicians in minimizing treatment-emergent sexual dysfunction (TESD) while treating depression. Vascular, hormonal, neurogenic, and pharmacological factors should be considered when a patient presents with SD. We also recommend that physicians obtain patient information about baseline and historical sexual functioning before prescribing a drug that may lead to SD and follow up accordingly. When the goal is to treat depression while attenuating the risk of sexual symptoms, physicians may wish to consider agomelatine, bupropion, desvenlafaxine, moclobemide, trazodone, vilazodone, and vortioxetine.

Selective Serotonin Reuptake Inhibitors

The first antidepressants were created by chance but brought the idea that central serotonin agonism produced an antidepressant effect. SSRIs were the first class of psychotropic medications to be rationally designed, meaning that researchers intended to utilize a specific mechanism of action while avoiding adverse effects. In this way, SSRIs were created to be safer and more tolerable than previous antidepressants. SSRIs share many similarities, but differ in terms of pharmacokinetics and effects on CYP450 enzymes, which is detailed in this chapter. Further information will be provided regarding safety, clinical indications/uses, and dosing recommendations.

Efficacy and tolerability of different doses of three new antidepressants for treating major depressive disorder: A PRISMA-compliant meta-analysis

In last decade, the US FDA has approved three new antidepressants: vortioxetine, levomilnacipran, and vilazodone. Many studies have researched the effects of these antidepressants on major depressive disorder (MDD), but they have not determined the optimum dosage. This meta-analysis investigated the efficacies of these three drugs at different dosages in the treatment of MDD. The PubMed, Embase, Cochrane Library, psycINFO, and ClinicalTrials.gov databases were searched to identify relevant literature. The primary outcomes were efficacy [quantified as the change from baseline in total score on the Montgomery-Asberg Depression Rating Scale (MADRS)] and tolerability (discontinuations due to adverse events). The effect size was quantified as the weighted mean difference for continuous data and the risk ratio (RR) for dichotomous data. Overall 22 studies were included. The changes in the MADRS total score were significantly higher for vortioxetine at 5, 10, 20, and 10-20 mg/day than for placebo. The tolerability was significantly worse for 20 mg/day vortioxetine than for placebo (RR = 1.84, 95% confidence interval = 1.13 to 3.02). In addition, increasing the dosage improved the efficacy of vortioxetine but worsened the tolerability. Levomilnacipran and vilazodone at any dosage produced a significantly higher mean change from baseline in the MADRS total score and a worse tolerability than for placebo. In conclusion, considering both efficacy and tolerability, 10 mg/day vortioxetine might be optimal for the treatment of MDD. The long-term efficacy and safety of vortioxetine needed to be investigated, and more studies of levomilnacipran and vilazodone are needed to define their optimal dosages.

Shortened Spadin Analogs Display Better TREK-1 Inhibition, In Vivo Stability and Antidepressant Activity

Depression is a devastating mental disorder that affects 20% of the population worldwide. Despite their proven efficacy, antidepressants present a delayed onset of action and serious adverse effects. Seven years ago, we described spadin (PE 12-28) as a promising endogenous peptide with antidepressant activity. Spadin specifically blocks the TREK-1 channel. Previously, we showed in vivo that, spadin activity disappeared beyond 7 h after administration. In order to improve in vivo spadin stability and bioavailability, we screened spadin analogs and derivatives. From the study of spadin blood degradation products, we designed a 7 amino-acid peptide, PE 22-28. In vitro studies on hTREK-1/HEK cells by using patch-clamp technique, showed that PE 22-28 displayed a better specificity and affinity for TREK-1 channel compared to spadin, IC₅₀ of 0.12 nM vs. 40–60 nM for spadin. In the same conditions, we also pointed out that different modifications of its N or C-terminal ends maintained or abolished TREK-1 channel activity without affecting PE 22-28 affinity. In vivo, the antidepressant properties of PE 22-28 and its derivatives were demonstrated in behavioral models of depression, such as the forced swimming test. Mice treated with spadin-analogs showed a significant reduction of the immobility time. Moreover, in the novelty suppressed feeding test after a 4-day sub-chronic treatment PE 22-28 reduced significantly the latency to eat the food pellet. PE 22-28 and its analogs were able to induce neurogenesis after only a 4-day treatment with a prominent effect of the G/A-PE 22-28. On mouse cortical neurons, PE 22-28 and its derivatives enhanced synaptogenesis measured by the increase of PSD-95 expression level. Finally, the action duration of PE 22-28 and its analogs was largely improved in comparison with that of spadin, up to 23 h instead of 7 h. Taken together, our results demonstrated that PE 22-28 and its derivatives represent other promising molecules that could be an alternative to spadin in the treatment of depression.

Suppressive Effect of Ginsenoside Rg3 against Lipopolysaccharide-Induced Depression-Like Behavior and Neuroinflammation in Mice

Ginsenoside Rg3 (Rg3), a major active ingredient enriched in red ginseng, possesses well-confirmed immunoregulatory effects. Immune disturbance is a common trigger and aggravating factor of depression. The aim of this study was to explore the effects of Rg3 on lipopolysaccharide (LPS)-induced depression-like behavior in mice and the involvement of immune regulation. Pretreatment with Rg3 (i.g., 20 and 40 mg/kg) effectively ameliorated LPS (i.p., 0.83 mg/kg) induced body weight loss, anorexia, and immobility time in both the tail suspension test and the forced swimming test. Rg3 attenuated the disturbed turnover of tryptophan and serotonin in the hippocampus, accompanied by decreased mRNA expression of pro-inflammatory cytokines and indoleamine-2,3-dioxygenase (IDO). These central benefits were partially linked to the regulation of microglia activation and nuclear factor kappa B (NF-κB) pathway. In addition, Rg3 significantly reduced LPS-induced elevation of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in plasma, and restored the systemic balance of tryptophan-kynurenine metabolism. Taken together, our results demonstrated that Rg3 was effective in ameliorating depressive-like behavior induced by immune activation, adding new evidence to support its health benefits by immunoregulation.

Advances in antidepressants for treating post-stroke depression

INTRODUCTION

Post-stroke depression (PSD) is a common and serious complication after stroke, occurring in nearly one third of stroke survivors, and affecting mortality rate, functional outcome, rehabilitation results and quality of life. However, in the common clinical practice only a minority of patients are properly treated. A relatively small number of scientific reports are available on clinical usefulness and safety of antidepressants (ADs) in PSD. Areas covered: This report provides an updated review about pharmacological state of art of PSD, including efficacy and safety of different drugs and their role on prevention, treatment and functional outcome. Expert opinion: Even if currently an antidepressant treatment can improve depressive symptoms, neither the optimal drug nor the optimal lengths of treatment, have been identified. Serotonergic drugs are preferable because of their better safety profile, but in the recent years there has been an important debate on possible association between selective serotonin reuptake inhibitor use and increased mortality. Another issue is the potential role of ADs for improving functional recovery. Newer ADs have interesting properties, in particular vortioxetine, due to its properties of enhancing cognitive functions, but further research is needed to clarify its/their role in treatment of PSD.

How do antidepressants work? New perspectives for refining future treatment approaches

Most currently available antidepressants target monoamine neurotransmitter function. However, a purely neurotransmitter-based explanation for antidepressant drug action is challenged by the delayed clinical onset of most agents and the need to explain how neurochemical changes reverse the many different symptoms of depression. Novel approaches to understanding of antidepressant drug action include a focus on early changes in emotional and social processing and the role of neural plasticity. In this Review, we discuss the ways in which these two different theories reflect different or complementary approaches, and how they might be integrated to offer novel solutions for people with depression. We consider the predictions made by these mechanistic approaches for the stratification and development of new therapeutics for depression, and the next steps that need to be made to facilitate this translation of science to the clinic.

The Role of Levomilnacipran in the Management of Major Depressive Disorder: A Comprehensive Review

Levomilnacipran, the more active enantiomer of the serotonin and norepinephrine reuptake inhibitor (SNRI) milnacipran, was recently approved in the US for the treatment of major depressive disorder (MDD). The drug was developed as an extended release (ER) capsule formulation to allow for once-daily administration, thereby improving patient adherence. This agent differs from other available SNRIs in having a greater potency for inhibition of norepinephrine relative to serotonin reuptake. The efficacy of levomilnacipran ER has been evaluated in seven randomised, double-blind clinical trials (one Phase II and four Phase III trials, and two long-term efficacy studies). These studies documented that levomilnacipran is generally more effective than placebo for the treatment of MDD in the short-term, whereas no firm evidence exists on long-term efficacy for relapse prevention. Preliminary evidence suggests that levomilnacipran ER may be effective in improving not only depressive symptoms but also symptoms related to functioning (social life, work, and family life). Short-and longer-term studies found that the rate of withdrawal from levomilnacipran therapy due to adverse events was rather low. Moreover the drug appeared to be generally well tolerated. The most common adverse effects included nausea, hyperhidrosis, constipation, tachycardia, palpitations, erectile dysfunction and ejaculation disorder. As hypertension or orthostatic hypotension may occur in a few patients, the cardiovascular safety of levomilnacipran needs to be more extensively investigated especially on long-term treatment. Additional active comparator trials evaluating efficacy, tolerability and cost-effectiveness are required to better define the role of levomilnacipran ER in the treatment of MDD in relation to currently available antidepressants including other SNRIs.

Raising the Minimum Effective Dose of Serotonin Reuptake Inhibitor Antidepressants: Adverse Drug Events

This review focuses on the dose-response of serotonin reuptake inhibitor (SRI) antidepressants for efficacy and for adverse drug events (ADEs). Dose-response is identified by placebo-controlled, double-blind, fixed-dose clinical trials comparing various doses for efficacy and for ADEs. Reports from the great majority of clinical trials have consistently found that the minimum SRI effective dose is usually optimal for efficacy in the treatment of depression disorders, even though most American medical practitioners raise the dose when early antidepressant treatment results are negative or partial. To better understand this issue, the medical literature was comprehensively reviewed to ascertain the degree to which SRI medications resulted in a flat dose response for efficacy and then to identify specific ADEs that are dose-dependent. Strong evidence from fixed-dose trial data for the efficacy of nonascendant, minimum effective doses of SRIs was found for the treatment of both major depression and anxiety disorders. Particularly important was the finding that most SRI ADEs have an ascending dose-response curve. These ADEs include sexual dysfunction, hypertension, cardiac conduction risks, hyperglycemia, decreased bone density, sweating, withdrawal symptoms, and agitation. Thus, routinely raising the SRI dose above the minimum effective dose for efficacy can be counter-productive.

Current Problems in the Research and Development of more Effective Antidepressants

This commentary was stimulated by discussions held at the First China Antidepressants Research and Development Summit held in Beijing in October 2015. Hosted by the Chinese Psychiatrist Psychopharmacology Commission and including leading clinicians, neuroscientists, and representatives of the pharmaceutical industry, the summit focused on the major problems that are limiting the development of more effective antidepressant medications. In the absence of clear biomarkers of depression, clinicians must base treatment decisions on clinical phenomenology; the lack of clear biological targets results in currently available antidepressants that take a long time to be effective, have low rates of full remission, and high rates of relapse. Basic research on depression by neuroscientists in China is internationally recognized, but the vast proportion of candidate chemical compounds Chinese researchers propose as potential treatments for depression fail when tested clinically. This high failure rate of proposed agents has rapidly increased the cost of bringing new drugs to market, so pharmaceutical firms prefer to ‘tweak’ currently approved medications rather than take the financial risk of supporting the development of novel antidepressants. Thus, the development of new, more effective treatments for depression is at a stalemate. Given the huge impact of depression on the economic development of China and other countries, it is essential to actively solicit the support of governments and communities in the efforts of clinicians, researchers, and the pharmaceutical industry to overcome this stalemate.

Personalizing supportive care in oncology patients using pharmacogenetic-driven treatment pathways

Cancer patients frequently suffer from disease- and treatment-related pain, nausea and depression, which severely reduces patients' quality of life. It is critical that clinicians are aware of drug-gene interactions and recognize the utility of applying pharmacogenetic information to personalize and improve supportive care. Pharmacogenetic-based algorithms may enhance clinical outcomes by allowing the clinician to select the 'least genetically vulnerable' drug. This review summarizes clinically relevant drug-gene interactions and presents pharmacogenetic-driven treatment pathways for depression, nausea/vomiting and pain. Ideally, this review provides a resource for clinicians to consult when selecting pharmacotherapy for a patient who presents with limited pharmacogenetic test results, with the hope of better controlling burdensome symptoms and improving the quality of life for cancer patients.

The serotonergic system in the neurobiology of depression: Relevance for novel antidepressants

The monoamine hypothesis of depression posits that an imbalance in monoaminergic neurotransmission is causally related to the clinical features of depression. Antidepressants influencing serotonin mainly aim at raising serotonin concentrations, thereby increasing serotonergic transmission at the level of the synapse, for example by inhibiting the serotonin transporter. However, the serotonin system is multifaceted. Different serotonin receptor subtypes turn the serotonergic system into a complex neurochemical arrangement that influences diverse neurotransmitters in various brain regions. Classical antidepressants as well as other psychopharmacological agents have various crucial effects on serotonin receptors. We aim at providing a clinically useful characterization of serotonin receptor subtypes in the treatment of depression. Clarifying the mode of action and the interplay of serotonin receptors with pharmacological agents should help antidepressant mechanisms and typical side effects to be better understood. Against this background, we feature the novel antidepressants vortioxetine, vilazodone and milnacipran/levomilnacipran with regard to their serotonin receptor targets such as the 5-HT1A, 5-HT3 and 5-HT7 which may account for their specific effects on certain symptoms of depression (e.g. cognition and anxiety) as well as a characteristic side-effect profile.

The noradrenergic paradox: implications in the management of depression and anxiety

Both major depressive disorder and the anxiety disorders are major causes of disability and markedly contribute to a significant global burden of the disease worldwide. In part because of the significant socioeconomic burden associated with these disorders, theories have been developed to specifically build clinical treatment approaches. One such theory, the monoaminergic hypothesis, has led to the development of several generations of selective and nonselective inhibitors of transporters of serotonin and norepinephrine, with the goal of augmenting monoaminergic transmission. These efforts have led to considerable success in the development of antidepressant therapeutics. However, there is a strong correlation between enhanced noradrenergic activity and fear and anxiety. Consequently, some physicians have expressed concerns that the same enhanced noradrenergic activity that alleviates depression could also promote anxiety. The fact that the serotonergic and noradrenergic reuptake inhibitors are successfully used in the treatment of anxiety and panic disorders seems paradoxical. This review was undertaken to determine if any clinical evidence exists to show that serotonergic and noradrenergic reuptake inhibitors can cause anxiety. The PubMed, EMBASE, and Cochrane Library databases were searched, and the results limited to randomized, double-blind, placebo-controlled studies performed in nongeriatric adults and with clear outcome measures were reported. Based on these criteria, a total of 52 studies were examined. Patients in these studies suffered from depression or anxiety disorders (generalized and social anxiety disorders, panic disorder, and posttraumatic stress disorder). The large majority of these studies employed venlafaxine or duloxetine, and the remainder used tri-cyclic antidepressants, atomoxetine, or reboxetine. All the studies reported clinically significant alleviation of depressive and/or anxious symptoms by these therapeutics. In none of these studies was anxiety a treatment-emergent adverse effect. This review argues against the impression that enhanced generalized noradrenergic activity promotes the emergence of anxiety.

Sexual side-effects of antidepressant and antipsychotic drugs

PURPOSE OF REVIEW

Psychotropic-related sexual dysfunction is a quite frequent issue in clinical practice, mainly in chronic treatments affecting both quality of life and compliance.

RECENT FINDINGS

In the last decade fortunately antidepressants and antipsychotic compounds have been deeply screened in order to identify sexual adverse events that were commonly underdiagnosed and previously underestimated by clinicians and perhaps by pharmaceutical companies as well. Some differences in the mechanism of action are the nucleus of this poorly tolerated adverse event. All antidepressants with serotonergic activity can cause mild to severe sexual dysfunction such as decreased libido and delayed orgasm frequently (>60%) or anorgasmia and arousal difficulties sometimes (30%). In contrast, noradrenergic, dopaminergic, or melatonergic antidepressants do not cause sexual dysfunction but perhaps the clinical profile of patients receiving these compounds could be different. Antipsychotics that highly increase prolactin levels and strongly block dopamine receptors could be related to sexual dysfunction as well. Unfortunately, these dysfunctions are present during the long term after the antipsychotic onset to provide continued symptom control and enable recovery. Young patients suffering psychosis and concomitant sexual dysfunction (erectile and/or orgasmic difficulties) tend to show poor compliance in chronic treatments affecting the outcomes.

SUMMARY

The implications of psychotropic-related sexual dysfunction in clinical practice are relevant mainly in patients under long-term treatment with previous satisfactory sexual life. Implications for future research about sexual dysfunction in all new treatments should be strongly taken into account.

Health resource use and costs of vilazodone and other selective serotonin re-uptake inhibitors in treating major depressive disorder

OBJECTIVE

Selective serotonin re-uptake inhibitors (SSRIs) are widely prescribed antidepressants. This claims database study compared healthcare resource use and costs among patients with major depressive disorder (MDD) treated with vilazodone vs other SSRIs.

METHODS

Adults with an MDD diagnosis and ≥ 1 prescription fill for vilazodone, citalopram, escitalopram, fluoxetine, paroxetine, or sertraline were identified from administrative claims data (2010-2012). Patients who concomitantly used adjunctive medication, either a second-generation antidepressant or antipsychotic, were excluded. All-cause and MDD-related healthcare resource use and costs (in 2012 USD) were compared between patients treated with vilazodone vs other SSRIs over a 6-month follow-up period using unadjusted and multivariable analyses.

RESULTS

The study cohort included 49 861 patients (mean age = 44.0 years; 70% female). Compared with the vilazodone cohort (n = 3527), patients in the citalopram (n = 12 187), escitalopram (n = 8275), fluoxetine (n = 10 142), paroxetine (n = 3146), and sertraline (n = 12 584) cohorts had significantly more all-cause inpatient hospital visits, longer hospital stays and more frequent emergency department visits, following the index date, after adjusting for baseline characteristics. All-cause medical service costs (inpatient + outpatient + emergency department visits) were significantly higher across all other SSRI cohorts vs vilazodone by $758-$1165 (p < 0.05). Similarly, all-cause total costs, were significantly or numerically (non-significantly) higher across all SSRI cohorts vs vilazodone by $351-$780.

LIMITATIONS

The was no clinical measurement of disease severity, partial coverage of the Medicare-eligible population, and short follow-up.

CONCLUSION

MDD treatment with vilazodone was associated with significantly lower rates of inpatient and emergency services, and with significantly lower all-cause medical service costs and numerically (non-significantly) lower total costs to payers than with the other SSRIs included in this study.