A double-blind, randomized, placebo-controlled, fixed-dose phase III study of vilazodone in patients with generalized anxiety disorder

Meta-analysis of the comparative efficacy of benzodiazepines and antidepressants for psychic versus somatic symptoms of generalized anxiety disorder

BACKGROUND

Benzodiazepines and antidepressants are effective agents for the treatment of generalized anxiety disorder (GAD), with the HAM-A frequently used as a primary outcome measure. The GAD literature is inconsistent regarding which medications are more effective for somatic versus psychic symptoms of GAD, and treatment guidelines do not advocate for prescribing based on subtype. This meta-analysis aimed to determine whether benzodiazepines and antidepressants have a differential impact on the somatic versus psychic subscales of the HAM-A in GAD.

METHODS

An electronic search was undertaken for randomized controlled trials of either benzodiazepines or antidepressants for GAD that reported treatment response using the HAM-A subscales. Data were extracted by independent reviewers. A random effects assessment of weighted mean difference with 95% confidence intervals and subgroup difference was applied. All analysis was done on SPSS 26. An assessment of bias, and of quality of evidence was performed.

RESULTS

24 randomized controlled trials met the inclusion criteria: 18 antidepressant trials, 5 benzodiazepine trials and 1 of both. 14 studies were assessed as having between some and high risk of bias, while 10 were assessed as having low risk of bias. Benzodiazepines (WMD of 1.81 [CI 1.03, 2.58]) were significantly more effective than antidepressants (WMD of 0.83 [CI 0.64, 1.02]) for reducing somatic symptoms of GAD (Chi2 = 5.81, p = 0.02), and were also more effective (WMD of 2.46 [CI 1.83, 3.09]) in reducing psychic symptoms than antidepressants (WMD of 1.83 [CI 1.55, 2.10]), although this comparison did not reach statistical significance (Chi2 = 3.31, p = 0.07).

CONCLUSION

The finding that benzodiazepines were significantly more effective than antidepressants for somatic symptoms needs to be weighed up against potential benefits of antidepressants over benzodiazepines. It may be useful for future treatment guidelines for GAD to explicitly consider symptom subtype.

Quantitative investigation of drug-drug interaction between bergenin and vilazodone in rats through UPLC-MS/MS assay

In this study, we firstly established and verified a method by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for the analysis of vilazodone and its metabolite M10 in rat plasma, then this method was used to explore the pharmacokinetics of vilazodone and M10 present or absence of 80 mg/kg bergenin in rats. Protein precipitation with acetonitrile was used to prepare the samples in this research. The mobile phase for liquid chromatography was consisted of 0.1% formic acid aqueous solution and acetonitrile. Brexpiprazole was used as the internal standard (IS), and the multiple reaction monitoring (MRM) mode was used for detection. The verification items required by the US Food and Drug Administration (FDA) guidelines such as selectivity, sensitivity, linearity, stability, recovery and matrix effect of this method were all met the standards. Besides, rats were used to explore the drug-drug interaction between vilazodone and bergenin, which were divided into two groups, and separately gavaged with the same-volume of carboxymethyl cellulose sodium (CMC-Na) solution and 80 mg/kg bergenin, respectively. The results showed that bergenin significantly affected the metabolism of vilazodone. It suggested that there was a potential drug-drug interaction between bergenin and vilazodone in rats. In clinical application, we should pay attention to the dose of vilazodone when in combination with bergenin.

Vilazodone for Major Depression in Adults: Pharmacological Profile and an Updated Review for Clinical Practice

This article provides an updated review of the pharmacological profile and available efficacy and tolerability/safety data for vilazodone, one of the most recent antidepressant drugs to be approved in the USA for the treatment of major depressive disorder (MDD) in adults. The efficacy of vilazodone for MDD in adults is supported by four positive short-term (8-10 weeks), randomized, placebo-controlled trials. Beyond these pivotal trials, we review updated research findings pertaining to the clinical effects of vilazodone for MDD including the results of switch studies, small comparative efficacy trials, key pooled and secondary data analyses focused on important depressive subtypes (anxious depression) and predictors of treatment outcome, and safety studies including direct studies of sexual side-effects. Despite these additional research efforts and use for over a decade, important gaps in the clinical evidence base remain with vilazodone. Hypothesized differences in efficacy and adverse effects between other antidepressants and vilazodone based on its multimodal mechanism of action (combining serotonin reuptake inhibition with serotonin 5-HT1A partial agonist effects) have not been comprehensively demonstrated in clinical studies and its effectiveness as a continuation- or maintenance-phase therapeutic is not yet established. Questions remain regarding its reproductive and lactational safety profiles and its efficacy as a potential next-step therapeutic for patients with MDD who do not respond to first-line antidepressants such as selective serotonin reuptake inhibitors. Suggestions for clinical use of vilazodone and discussion of its place among the broad range of pharmacotherapies for adults with MDD are provided.

The binding mode of vilazodone in the human serotonin transporter elucidated by ligand docking and molecular dynamics simulations

Vilazodone is a novel antidepressant used for the treatment of major depressive disorder (MDD) with a primary action mechanism of inhibiting the human serotonin reuptake transporter (hSERT) and acting as a 5-HT_1A receptor partial agonist. The interaction between vilazodone and the 5-HT_1A receptor has been reported, however, the binding mode of vilazodone in the hSERT remains elusive. In the current study, to elucidate the molecular mechanism of vilazodone binding in the hSERT, the drug and its five analogs were docked into the hSERT crystal structure as initial conformations and were sampled by 400 ns molecular dynamics (MD) simulations. Through the analysis of the profiles of protein-ligand binding free energies, interaction fingerprints, and conformational rearrangements, the binding mode of vilazodone in the hSERT was revealed. As a result, unlike the classical antidepressants located in the S1 site of the hSERT, vilazodone adopted a linear pose in the binding pocket. Its arylpiperazine fragment occupies the central site (S1) and interacts with Y95, D98, I172, Y176, F335, F341, S438, and T439, while the indole fragment extends to the allosteric site (S2) via interacting with the ionic switch (R104/E403) between the two sites. The new insights obtained are not only helpful in understanding the binding mode of vilazodone in the hSERT, but also provide valuable guidance to the discovery of novel antidepressant drugs.

Current and Novel Psychopharmacological Drugs for Anxiety Disorders

Anxiety disorders, including panic disorder/agoraphobia (PDA), generalized anxiety disorder (GAD), social anxiety disorder (SAD), and others, are the most prevalent mental disorders. In this paper, recommendations are given for the psychopharmacological treatment of these disorders which are based on comprehensive treatment guidelines, meta-analyses, and systematic reviews of available randomized controlled studies. Anxiety disorders can effectively be treated with psychotherapy, pharmacotherapy, or a combination of both. First-line drugs are the selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). Benzodiazepines are not recommended for routine use due to their possible addiction potential. Other treatment options include the calcium modulator pregabalin, tricyclic antidepressants, buspirone, moclobemide, and others. Drug treatment can be combined with psychological treatments. Novel treatment strategies include medications that act on GABA, glutamate, and other neurotransmitter systems. After remission, medications should be continued for 6 to 12 months.

Pharmacological and psychological interventions for generalized anxiety disorder in adults: A network meta-analysis

Generalized anxiety disorder (GAD) is a significant and common mental illness with a lifetime prevalence of 3.7%. Regardless of the complexity of treatment decisions for GAD, few studies have conducted systematic comparisons of the efficacies of varying interventions. Thus, this study performed a valid network meta-analysis (NMA) of randomized controlled trials (RCTs) to synthesize direct and indirect evidence for alternative interventions for GAD. We searched four major bibliographic databases, the Cochrane Central Register of Controlled Trials, Embase, PsycINFO, and PubMed, for published RCTs of adult patients with a diagnosis of GAD and allowed for all comorbidities. A total of 91 articles (14,812 participants) were identified in the final NMA. The results showed that all pharmacological treatments except for serotonin modulators and second-generation antipsychotics had greater effects than placebo: norepinephrine-dopamine reuptake inhibitors (standardized mean difference (SMD) -1.84, 95% credible interval -3.05 to -0.62), noradrenergic and specific serotonergic antidepressants (-0.91, -1.62 to -0.20), melatonergic receptor agonists (-0.68, -1.15 to -0.21), selective serotonin reuptake inhibitors (SSRIs; -0.67, -0.90 to -0.43), azapirones (-0.58, -1.00 to -0.17), anticonvulsants (-0.56, -0.85 to -0.28), serotonin-norepinephrine reuptake inhibitors (SNRIs; -0.54, -0.79 to -0.30), and benzodiazepines (BZDs; -0.40, -0.65 to -0.15). Most psychological and self-help interventions exerted greater effects than the waitlist group. However, no psychological interventions had greater effects compared with the psychological placebo. Overall, most pharmacological interventions had larger effect sizes than psychological interventions, and most psychological interventions showed larger effect sizes than self-help interventions.

Interleukin-4 signalling pathway underlies the anxiolytic effect induced by 3-deoxyadenosine

RATIONALE

Converging evidence suggests that neuroimmunity plays an important role in the pathophysiology of anxiety. Interleukin (IL)-4 is a key cytokine regulating neuroimmune functions in the central nervous system. More efficient anxiolytics with neuro-immune mechanisms are urgently needed.

OBJECTIVE

To determine whether 3'-deoxyadenosine (3'-dA) exerts an anxiolytic effect and to examine the role of IL-4 in the anxiolytic effect of 3'-dA in mice.

METHODS

We investigated the effects of 3'-dA on anxiety-like behaviors using elevated plus maze (EPM) or light-dark box (LDB) tests after 45 min or 5 days of treatment. Expression of IL-4, IL-10, IL-1β, TNF-α, and IL-6 in the prefrontal cortex (PFC) was detected by Western blot and/or double immunostaining. Intracerebroventricular injection of RIL-4Rα (an IL-4-specific inhibitor) and intraperitoneal injection of 3'-dA or imipramine were co-administered, followed by EPM test.

RESULTS

3'-dA exhibited a stronger and faster anxiolytic effect than imipramine in behavioral tests. Furthermore, 3'-dA enhanced IL-4 expression after 45 min or 5 days, TNF-α and IL-1β expression decreased significantly after a 5-day treatment with 3'-dA, and IL-10 expression increased after a 5-day treatment with 3'-dA or imipramine in the PFC. IL-4 was expressed in neurons and in some astrocytes and microglia. IL-4 expression showed a strong positive correlation with reduced anxiety behaviors. RIL-4Rα completely blocked the anxiolytic effects induced by 3'-dA and imipramine.

CONCLUSIONS

This study identifies a novel and common anxiolytic IL-4 signaling pathway and provides an innovative drug with a novel neuro-immune mechanism for treating anxiety disorder.

Psychological and pharmacological treatments for generalized anxiety disorder (GAD): a meta-analysis of randomized controlled trials

The purpose of this meta-analysis was to provide updated pooled effect sizes of evidence-based psychotherapies and medications for generalized anxiety disorder (GAD) and to investigate potential moderators of outcomes. Seventy-nine randomized controlled trials (RCT) including 11,002 participants with a diagnosis of GAD were included in a meta-analysis that tested the efficacy of psychotherapies or medications for GAD. Psychotherapy showed a medium to large effect size (g = 0.76) and medication showed a small effect size (g = 0.38) on GAD outcomes. Psychotherapy also showed a medium effect on depression outcomes (g = 0.64) as did medications (g = 0.59). Younger age was associated with a larger effect size for psychotherapy (p < 0.05). There was evidence of publication bias in psychotherapy studies. This analysis found a medium to large effect for empirically supported psychotherapy interventions on GAD outcomes and a small effect for medications on GAD outcomes. Both groups showed a medium effect on depression outcomes. Because medication studies had more placebo control conditions than inactive conditions compared to psychotherapy studies, effect sizes between the domains should not be compared directly. Patient age should be further investigated as a potential moderator in psychotherapy outcomes in GAD.

Evaluation of vilazodone for the treatment of depressive and anxiety disorders

INTRODUCTION

Major Depressive Disorder (MDD) and General Anxiety Disorder (GAD) significantly contribute to the global burden of disease. Vilazodone, a combined serotonin reuptake inhibitor and 5-HT1A partial agonist, is an approved therapy for the treatment of MDD and which has been further investigated for GAD. Areas covered: This article covers the pharmacokinetics and pharmacodynamics of vilazodone and provides an evaluation of the clinical usefulness of vilazodone for the treatment of MDD and anxiety disorders. A literature search was performed using PubMed/MEDLINE, Web of Science and the Cochrane Library. Expert opinion: Studies have shown that vilazodone is significantly superior to placebo. However, vilazodone cannot as yet be recommended as a first-line treatment option for MDD as it is unclear whether the drug's dual mechanism of action provides greater efficacy than prevailing treatment options. Moreover, more phase IV studies are needed to establish its efficacy and long-term safety in larger and more diverse populations. Although vilazodone may have an additional advantage for the treatment of anxiety symptoms in MDD, here also additional studies are required to confirm its efficacy over and above SSRI alternatives and other antidepressant treatments. Therefore, presently, vilazodone should be considered as a second- or third-line treatment option for MDD and GAD.

Pharmacotherapy for generalized anxiety disorder in adult and pediatric patients: an evidence-based treatment review

INTRODUCTION

Generalized anxiety disorder (GAD) often begins during adolescence or early adulthood and persists throughout the lifespan. Randomized controlled trials support the efficacy of selective serotonin and selective serotonin norepinephrine reuptake inhibitors (SSRIs and SNRIs, respectively), as well as benzodiazepines, azapirones, anti-adrenergic medications, melatonin analogs, second-generation antipsychotics, kava, and lavender oil in GAD. However, psychopharmacologic treatment selection requires clinicians to consider multiple factors, including age, co-morbidity, and prior treatment. Areas covered: The authors review the literature concerning pharmacotherapy for pediatric and adult patients with GAD with specific commentary on the efficacy and tolerability of selected agents in these age groups. The authors describe an algorithmic approach to the pediatric and adult patient with GAD and highlight considerations for the use of selected medications in these patients. Expert opinion: In adults with GAD, SSRIs and SNRIs represent the first-line psychopharmacologic treatment while second-line pharmacotherapies include buspirone, benzodiazepines, SGAs, and pregabalin. In pediatric patients with GAD, SSRIs should be considered the first line pharmacotherapy and psychotherapy enhances antidepressant response.

Comparing the efficacy of benzodiazepines and serotonergic anti-depressants for adults with generalized anxiety disorder: a meta-analytic review

INTRODUCTION

Generalized anxiety disorder (GAD) is a common form of anxiety disorder. Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and benzodiazepines (BZs) are the most commonly prescribed medications for GAD, but little is known about the relative efficacy of these pharmacological treatments. Areas covered: This study provides a meta-analytic review of the efficacy of these medications in the treatment of adults with GAD. A comprehensive literature search yielded 54 articles reporting 56 unique studies with 12,655 participants treated with either pill placebo (6,191 participants), SSRIs (16 trials, 2,712 participants), SNRIs (17 trials, 2,603 participants), or BZs (23 trials, 1,149 participants). The overall combined effect size was modest to moderate (Hedges' g = 0.37, p < 0.0001). Effect sizes decreased significantly over time. SSRIs (Hedges' g = 0.33) and SNRIs (Hedges' g = 0.36) demonstrated significantly lower effect sizes than BZs (Hedges' g = 0.50). These findings were not due to differences in treatment length or publication year. Expert opinion: The results of this study suggest that the most common forms of pharmacotherapy for adult GAD are moderately effective, with BZs being the most effective drug.

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.

Effects of vilazodone on suicidal ideation and behavior in adults with major depressive disorder or generalized anxiety disorder: post-hoc analysis of randomized, double-blind, placebo-controlled trials

Treatment-emergent suicidal ideation and behavior are ongoing concerns with antidepressants. Vilazodone, currently approved for the treatment of major depressive disorder (MDD) in adults, has also been evaluated in generalized anxiety disorder (GAD). Post-hoc analyses of vilazodone trials were carried out to examine its effects on suicidal ideation and behavior in adults with MDD or GAD. Data were pooled from vilazodone trials in MDD (four studies) and GAD (three studies). The incidence of suicide-related events was analyzed on the basis of treatment-emergent adverse event reporting and Columbia-Suicide Severity Rating Scale (C-SSRS) monitoring. Treatment-emergent suicidal ideation was analyzed on the basis of a C-SSRS category shift from no suicidal ideation/behavior (C-SSRS=0) at baseline to suicide ideation (C-SSRS=1-5) during treatment. In pooled safety populations (MDD, n=2233; GAD, n=1475), suicide-related treatment-emergent adverse events occurred in less than 1% of vilazodone-treated and placebo-treated patients. Incidences of C-SSRS suicidal ideation were as follows: MDD (vilazodone=19.9%, placebo=24.7%); GAD (vilazodone=7.7%, placebo=9.4%). Shifts from no suicidal ideation/behavior at baseline to suicidal ideation during treatment were as follows: MDD (vilazodone=9.4%, placebo=10.3%); GAD (vilazodone=4.4%, placebo=6.1%). Data from placebo-controlled studies indicate little or no risk of treatment-emergent suicidal ideation or behavior with vilazodone in adults with MDD or GAD. Nevertheless, all patients should be monitored for suicidal thoughts and behaviors during antidepressant treatment.

Anxiety disorders

Anxiety disorders constitute the largest group of mental disorders in most western societies and are a leading cause of disability. The essential features of anxiety disorders are excessive and enduring fear, anxiety or avoidance of perceived threats, and can also include panic attacks. Although the neurobiology of individual anxiety disorders is largely unknown, some generalizations have been identified for most disorders, such as alterations in the limbic system, dysfunction of the hypothalamic-pituitary-adrenal axis and genetic factors. In addition, general risk factors for anxiety disorders include female sex and a family history of anxiety, although disorder-specific risk factors have also been identified. The diagnostic criteria for anxiety disorders varies for the individual disorders, but are generally similar across the two most common classification systems: the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and the International Classification of Diseases, Tenth Edition (ICD-10). Despite their public health significance, the vast majority of anxiety disorders remain undetected and untreated by health care systems, even in economically advanced countries. If untreated, these disorders are usually chronic with waxing and waning symptoms. Impairments associated with anxiety disorders range from limitations in role functioning to severe disabilities, such as the patient being unable to leave their home.

Efficacy and tolerability of vilazodone for the acute treatment of generalized anxiety disorder: A meta-analysis

PURPOSE

A systematic review and meta-analysis of all relevant randomized controlled trials was conducted to evaluate the safety and efficacy of vilazodone in the acute treatment of generalized anxiety disorder (GAD).

METHODS

The literature was searched through all relevant databases in order to identify clinical trials on the use of vilazodone in the treatment of GAD. Once the trials were identified, data was extracted and analyzed using Revman5.3 and open meta-analyst. Assessment of continuous outcomes relied upon standardized mean difference, while binary outcomes were evaluated via relative risk, absolute risk reduction and NNT/NNH.

RESULTS

A total of 3 well-designed randomized controlled trials with a duration of 10 weeks were conducted, with a total of 844 (intent to treat population) randomized to vilazodone (20-40mg, mean dose=31.42mg) and 618 to placebo. The study drug was significantly superior (p<0.001) to placebo in continuous primary outcome measures (HAMA reduction at week 8, CGI-S reduction at week 8 and CGI-I score at week 8). Binary outcome measures however are not as promising, probably reflecting a small effect size [NNT=10 (6.67, 21.28) for induction of response according to the HAMA scale and NNT=12 (7.58, 34.48) for the CGI-I scale], although statistical significance (p<0.01) was attained for both. The study drug was significantly (p<0.001) more likely than placebo to induce adverse effects and to be discontinued due to adverse effects NNH=14 (10.31, 22.22), most common of which were nausea and diarrhea.

DISCUSSION

Vilazodone was superior to placebo in the short term treatment of GAD. However, due to the small effect size and high incidence of adverse events, the utility of vilazodone in the treatment of GAD remains unclear. Likelihood to be helped (HAMA response) or harmed (discontinuation due to adverse events) was inconclusive [1.4 (0.48, 3.33)], demonstrating a need for further trials and direct comparisons of vilazodone to the standard treatments for the disorder. Thus vilazodone cannot be recommended yet as a first line agent.

CONCLUSION AND LIMITATIONS

Vilazodone is an effective treatment for generalized anxiety disorder, though further trials are required for a more adequate comparison with established treatments, as well as long term maintenance studies to determine the validity of claims regarding the absence of sexual side effects.

Effects of vilazodone on sexual functioning in healthy adults: results from a randomized, double-blind, placebo-controlled, and active-controlled study

The aim of this study is to evaluate the effects of vilazodone on sexual functioning in healthy, sexually active adults and assess the impact of medication nonadherence in this type of trial. Participants were randomized to vilazodone (20 or 40 mg/day), paroxetine (20 mg/day), or placebo for 5 weeks of double-blind treatment. The primary endpoint was change from baseline to day 35 in Change in Sexual Functioning Questionnaire (CSFQ) total score in the intent-to-treat (ITT) population. Post-hoc analyses were carried out in modified intent-to-treat (mITT) populations that excluded participants in the active-treatment groups with undetectable plasma drug concentrations at all visits (mITT-I) or at least one visit (mITT-II). In the ITT population (N=199), there were no statistically significant differences between any treatment groups for CSFQ total score change: placebo, -1.0; vilazodone 20 mg/day, -1.4; vilazodone 40 mg/day, -1.9; and paroxetine, -3.5. In mITT-I (N=197) and mITT-II (N=159), CSFQ total score change was not significantly different between vilazodone (either dose) versus placebo; the CSFQ total score decreased significantly (P<0.05) with paroxetine versus both placebo and vilazodone 20 mg/day, but not versus vilazodone 40 mg/day. Vilazodone exerted no significant effect on sexual functioning in healthy adults. Medication nonadherence can alter study results and may be an important consideration in trials with volunteer participants.

Anxiety

Anxiety disorders (separation anxiety disorder, selective mutism, specific phobias, social anxiety disorder, panic disorder, agoraphobia, and generalised anxiety disorder) are common and disabling conditions that mostly begin during childhood, adolescence, and early adulthood. They differ from developmentally normative or stress-induced transient anxiety by being marked (ie, out of proportion to the actual threat present) and persistent, and by impairing daily functioning. Most anxiety disorders affect almost twice as many women as men. They often co-occur with major depression, alcohol and other substance-use disorders, and personality disorders. Differential diagnosis from physical conditions-including thyroid, cardiac, and respiratory disorders, and substance intoxication and withdrawal-is imperative. If untreated, anxiety disorders tend to recur chronically. Psychological treatments, particularly cognitive behavioural therapy, and pharmacological treatments, particularly selective serotonin-reuptake inhibitors and serotonin-noradrenaline-reuptake inhibitors, are effective, and their combination could be more effective than is treatment with either individually. More research is needed to increase access to and to develop personalised treatments.

Vilazodone for the Treatment of Depression: An Update

Vilazodone is a novel antidepressant having a selective serotonin (5-HT) reuptake inhibitor and 5-HT1A receptor partial agonist profile, so it has been regarded as a serotonin partial agonist-reuptake inhibitor (SPARI). We aimed to provide Vilazodone's clinical implications mainly by reviewing published clinical trials. Vilazodone has been speculated to have three potential benefits including faster onset of action, greater efficacy, and better tolerability owning to its SPARI properties. However, no studies conducted so far have directly proven the above speculations. Five initial phase II trials failed to distinguish vilazodone from placebo in the treatment of MDD, but 4 randomized clinical trials (RCT), 3 post-hoc or pooled analysis, 1 long-term open label study, and a meta-analysis showed vilazodone's superior efficacy over placebo. The studies also showed vilazodone is generally safe and tolerable. However, diarrhea, nausea, headache, dizziness, dry mouth, and insomnia warrant close attention in clinical practice because they have been constantly noted throughout the clinical studies. 2 RCTs recently documented the efficacy and safety of vilazodone in patients with generalized anxiety disorder, which could be a start of broadening vilazodone's usage or FDA approval in diverse anxiety disorders.

Post Hoc Analyses of Anxiety Measures in Adult Patients With Generalized Anxiety Disorder Treated With Vilazodone

Objective

To investigate vilazodone, currently approved for major depressive disorder in adults, for generalized anxiety disorder (GAD).

Method

Three randomized, double-blind, placebo-controlled studies showing positive results for vilazodone (2,040 mg/d) in adult patients with GAD (DSM-IV-TR) were pooled for analyses; data were collected from June 2012 to March 2014. Post hoc outcomes in the pooled intent-to-treat population (n = 1,462) included mean change from baseline to week 8 in Hamilton Anxiety Rating Scale (HARS) total score, psychic and somatic anxiety subscale scores, and individual item scores; HARS response (≥ 50% total score improvement) and remission (total score ≤ 7) at week 8; and category shifts, defined as HARS item score ≥ 2 at baseline (moderate to very severe symptoms) and score of 0 at week 8 (no symptoms).

Results

The least squares mean difference was statistically significant for vilazodone versus placebo in change from baseline to week 8 in HARS total score (−1.83, P < .0001) and in psychic anxiety (−1.21, P < .0001) and somatic anxiety (−0.63, P < .01) subscale scores; differences from placebo were significant on 11 of 14 HARS items (P < .05). Response rates were higher with vilazodone than placebo (48% vs 39%, P < .001), as were remission rates (27% vs 21%, P < .01). The percentage of patients who shifted to no symptoms was significant for vilazodone on several items: anxious mood, tension, intellectual, depressed mood, somatic-muscular, somatic-sensory, cardiovascular, respiratory, and autonomic symptoms (P < .05).

Conclusions

Treatment with vilazodone versus placebo was effective in adult GAD patients, with significant differences between treatment groups found on both psychic and somatic HARS items.

Trial Registration

ClinicalTrials.gov identifiers: NCT01629966, NCT01766401, NCT01844115.

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.

Characterizing sexual function in patients with generalized anxiety disorder: a pooled analysis of three vilazodone studies

BACKGROUND

Vilazodone has been shown to reduce core symptoms of generalized anxiety disorder (GAD) in three randomized, double-blind, placebo-controlled trials. Since sexual dysfunction (SD) is not well characterized in GAD, a post hoc analysis of these trials was conducted to evaluate the effects of vilazodone on sexual functioning in GAD patients.

MATERIALS AND METHODS

Data were pooled from one fixed-dose trial of vilazodone 20 and 40 mg/day (NCT01629966) and two flexible-dose studies of vilazodone 20-40 mg/day (NCT01766401, NCT01844115) in adults with GAD. Sexual functioning was assessed using the Changes in Sexual Functioning Questionnaire (CSFQ). Outcomes included mean change from baseline to end of treatment (EOT) in CSFQ total score and percentage of patients shifting from SD at baseline (CSFQ total score ≤47 for males, ≤41 for females) to normal functioning at EOT. Treatment-emergent adverse events related to sexual functioning were also analyzed.

RESULTS

A total of 1,373 patients were included in the analyses. SD at baseline was more common in females (placebo, 46.4%; vilazodone, 49%) than in males (placebo, 35.1%; vilazodone, 40.9%). CSFQ total score improvement was found in both females (placebo, +1.2; vilazodone, +1.6) and males (placebo, +2.1; vilazodone, +1.0), with no statistically significant differences between treatment groups. The percentage of patients who shifted from SD at baseline to normal sexual functioning at EOT was higher in males (placebo, 40.6%; vilazodone, 35.7%) than in females (placebo, 24.9%; vilazodone, 34.9%); no statistical testing was performed. Except for erectile dysfunction and delayed ejaculation in vilazodone-treated males (2.4% and 2.1%, respectively), no treatment-emergent adverse events related to sexual functioning occurred in ≥2% of patients in either treatment group.

CONCLUSION

Approximately 35%-50% of patients in the vilazodone GAD studies had SD at baseline. Vilazodone and placebo had similar effects on CSFQ outcomes in both females and males, indicating a limited adverse impact on sexual functioning with vilazodone.

INFLUENCE OF STUDY DESIGN ON TREATMENT RESPONSE IN ANXIETY DISORDER CLINICAL TRIALS

OBJECTIVE

The influence of study design variables and publication year on response to medication and placebo was investigated in clinical trials for social anxiety disorder (SAD), generalized anxiety disorder (GAD), and panic disorder (PD).

METHOD

Hierarchical linear modeling determined whether publication year, treatment assignment (medication vs. placebo), study type (placebo-controlled or active comparator), study duration, and the number of study visits affected the mean change associated with medication and placebo.

RESULTS

In the 66 trials examined, the change associated with both medication and placebo increased over time (t = 4.23, df = 39, P < .001), but average drug-placebo differences decreased over time (t = -2.04, df = 46, P = .047). More severe baseline illness was associated with greater drug-placebo differences for serotonin norepinephrine reuptake inhibitors (SNRIs, t = 3.46, df = 106, P = .001) and selective serotonin reuptake inhibitors (SSRI, t = 10.37, df = 106, P < .001). Improvement with medication was significantly greater in active-comparator studies compared to placebo-controlled trials (t = 3.41, df = 39, P = .002). A greater number of study visits was associated with greater symptom improvement in PD trials relative to SAD (t = 2.83, df = 39, P = .008) and GAD (t = 2.16, df = 39, P = .037).

CONCLUSIONS

Placebo response is substantial in SAD, GAD, and PD trials, and its rise over time has been associated with diminished drug-placebo differences. Study design features that influence treatment response in anxiety disorder trials include patient expectancy, frequency of follow-up visits, and baseline illness severity.

A 12-Week Double-Blind, Placebo-Controlled, Flexible-Dose Trial of Vilazodone in Generalized Social Anxiety Disorder

OBJECTIVE

To examine the efficacy, safety, and tolerability of vilazodone for subjects (aged 18-75 years) with generalized social anxiety disorder.

METHOD

Forty-four subjects with generalized social anxiety disorder (DSM-IV-TR criteria) were randomized to vilazodone or placebo in a 12-week double-blind, flexible-dose trial. Change from baseline to endpoint on the Liebowitz Social Anxiety Scale (LSAS) was the primary outcome measure. Secondary outcome measures included response and remission rates and changes in depression and anxiety. Data were collected between November 2012 and April 2014. The study was conducted at a private clinical trials facility in New York, New York.

RESULTS

The mean baseline LSAS score was 91.9 (SD = 17.5) and the mean Clinical Global Impressions-Severity scale score was 5.3 (SD = 0.56), indicating marked to severe illness. There were no significant baseline differences in severity of social anxiety between the treatment groups. At the end of treatment, in the intent-to-treat sample (n = 39), the vilazodone group had improved significantly more than the placebo group by 14.3 points on the LSAS (t = 1.80, P = .04, one-tail test) (Cohen d = 0.58).

CONCLUSIONS

The findings suggest that vilazodone may be a promising treatment for social anxiety disorder. Further study is needed given the limited sample size.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01712321.

Pharmacological treatment for generalized anxiety disorder in adults: an update

INTRODUCTION

Modest response and remission rates for the selective serotonin reuptake inhibitors and the serotonin-norepinephrine reuptake inhibitors, coupled with mounting evidence that the tolerability of the antidepressants (ADs) may have been overstated in the literature, has contributed to changes in prescribing patterns for generalized anxiety disorder (GAD). New interest in the absence of evidence that supports these standard therapies as superior to benzodiazepines stimulated a review of the literature.

AREAS COVERED

A literature search was conducted in the MedLine database with search terms 'generalized anxiety disorder' and 'treatment' for purposes of including relevant literature related to pharmacologic treatment of GAD. Aside from a review of pivotal literature, the authors also included newer studies that evaluated novel drug treatments. Last, the database was searched for benzodiazepine comparisons to standard therapy secondary to concerns that such literature is sparse. The review of newer modalities and the decision to include related literature was also based on the strength of the evidence and the status of their approval for the treatment of GAD.

EXPERT OPINION

Although ADs remain the most frequently prescribed medications for GAD, alternative and off-label therapies such as pregabalin, the atypical antipsychotics and vortioxetine are garnering interest. Based on the evidence available to us, it is our recommendation that along with the ADs, benzodiazepines be considered a possible first-line therapy in eligible patients based on the discretion and clinical judgment of the treating physician.

Vilazodone in patients with generalized anxiety disorder: a double-blind, randomized, placebo-controlled, flexible-dose study

Vilazodone is a selective serotonin reuptake inhibitor and a 5-HT1A receptor partial agonist that is approved for treatment of major depressive disorder in adults in the USA and Mexico. The efficacy, safety, and tolerability of vilazodone for generalized anxiety disorder (GAD) were investigated in a clinical trial (NCT01766401 ClinicalTrials.gov). Participants (18-70 years, inclusive) who met Diagnostic and Statistical Manual of Mental Disorders, 4th ed., text revision, criteria for GAD were randomized (1:1) to placebo or flexible-dose vilazodone (20-40 mg/day) for 8 weeks of double-blind treatment. Primary and secondary efficacy parameters were changes from baseline to week 8 in Hamilton Rating Scale for Anxiety and Sheehan Disability Scale total scores, respectively. Analysis was based on a mixed-effects model for repeated measures approach on the intent-to-treat population. The intent-to-treat population comprised 395 patients (placebo=197, vilazodone=198); 77% completed the study. The least squares mean difference in change from baseline to week 8 in the Hamilton Rating Scale for Anxiety total score was statistically significant for vilazodone versus placebo [-1.50 (-2.96, -0.04), P=0.0438]. The mean change from baseline to week 8 in the Sheehan Disability Scale total score for vilazodone versus placebo was not statistically significant. Adverse events were reported in 60% of placebo-treated and 83% of vilazodone-treated patients. This was a positive clinical trial of 20-40 mg/day vilazodone versus placebo in the treatment of GAD.

Evaluation of the efficacy and safety of vilazodone for treating major depressive disorder

PURPOSE

Vilazodone is a novel serotonin (5-HT)-reuptake inhibitor and 5-HT1A partial agonist that was recently developed for the treatment of major depressive disorder (MDD). We conducted a meta-analysis and systematic review to better evaluate the efficacy and safety of vilazodone.

MATERIALS AND METHODS

We performed a thorough literature search to identify all randomized double-blind placebo-controlled trials that were designed to investigate the efficacy of vilazodone for the treatment of MDD, and that were published in electronic databases, including Medline, Embase, and the Cochrane Central Register of Controlled Trials. A manual search was also conducted to investigate the relevant references of the retrieved studies. Subsequently, we conducted a meta-analysis and systematic literature review.

RESULTS

A total of five randomized controlled trials were finally included, involving 1,200 patients with vilazodone and 1,193 patients with placebo. The primary efficacy end point of the Montgomery-Åsberg Depression Rating Scale (standardized mean difference -3.58, 95% confidence interval -4.59 to -2.56; P<0.00001), and the key secondary efficacy end points (Clinical Global Impression - Severity scale, Clinical Global Impression - Improvement scale, and Hamilton Anxiety Rating Scale) indicated that vilazodone was more effective than placebo. Most common adverse events, including diarrhea and nausea, were evaluated, and safety assessments indicated that vilazodone was well tolerated (diarrhea odds ratio 3.54, 95% confidence interval 2.81-4.45; P<0.00001; nausea odds ratio 3.85, 95% confidence interval 3.00-4.96; P<0.00001; discontinuations due to adverse events odds ratio 2.71, 95% confidence interval 1.81-4.05; P<0.00001).

CONCLUSION

Our findings indicate that the novel antidepressant vilazodone is effective and safe for MDD, with a low occurrence of side effects. It offers promise as an effective oral drug for the treatment of MDD, with a balance of efficacy and tolerability.