Treatment for mood and anxiety disorders: quetiapine and aripiprazole

Polypharmacology of dopamine receptor ligands

Most neurological diseases have a multifactorial nature and the number of molecular mechanisms discovered as underpinning these diseases is continuously evolving. The old concept of developing selective agents for a single target does not fit with the medical need of most neurological diseases. The development of designed multiple ligands holds great promises and appears as the next step in drug development for the treatment of these multifactorial diseases. Dopamine and its five receptor subtypes are intimately involved in numerous neurological disorders. Dopamine receptor ligands display a high degree of cross interactions with many other targets including G-protein coupled receptors, transporters, enzymes and ion channels. For brain disorders like Parkinsońs disease, schizophrenia and depression the dopaminergic system, being intertwined with many other signaling systems, plays a key role in pathogenesis and therapy. The concept of designed multiple ligands and polypharmacology, which perfectly meets the therapeutic needs for these brain disorders, is herein discussed as a general ligand-based concept while focusing on dopaminergic agents and receptor subtypes in particular.

Aripiprazole: a clinical review of its use for the treatment of anxiety disorders and anxiety as a comorbidity in mental illness

BACKGROUND

Although anxiety disorders are common, optimal treatment is elusive. More than half of anxiety patients treated with an adequate course of antidepressants fail to fully improve: treatment resistance, residual symptoms, and recurrence/relapse remain a challenge. Recently, atypical antipsychotics have been considered for treatment-resistant anxiety disorders. This review will explore the available data for the role of aripiprazole in the treatment of anxiety.

METHODS

PubMed and conference abstracts were searched for randomized, double-blind studies that investigated the efficacy of aripiprazole in anxiety; its efficacy in bipolar disorder and depression was also explored for comparison.

RESULTS

A number of studies have shown atypical antipsychotics to be effective in anxiety, and currently available data suggest that aripiprazole augmentation in patients with anxiety disorders is likely as effective as other atypical antipsychotic drugs. Although there have been no randomized, controlled trials, aripiprazole has been found to be effective in treating anxiety disorders in two open-label trials. This combined with the larger data base demonstrating its utility in bipolar disorder and depression, its safety profile and its unique mechanism of action, make aripiprazole for anxiety an intriguing avenue of exploration.

LIMITATIONS

Data from large randomized, controlled trials on the use of atypical antipsychotics for anxiety in general, and aripiprazole in particular, are currently lacking.

CONCLUSION

The results of open-label trials of aripiprazole in anxiety provide enough support to warrant its further study. This, combined with a larger data base demonstrating its utility in bipolar disorder and depression, its safety profile and its unique mechanism of action, make aripiprazole for anxiety an intriguing avenue of exploration.

Quetiapine anxiolytic-like effect in the Vogel conflict test is serotonin dependent

There is growing evidence to show that atypical antipsychotic quetiapine might exert an anxiolytic effect in patients. Nevertheless, the mechanism underlying this effect has not yet been fully explored. Like other anxiolytic drugs, quetiapine exhibits partial agonistic activity toward serotonergic 1A (5HT1A) receptors. The involvement of the serotonin system in anxiety, particularly of 5HT1A receptors, has been widely documented. In this study we have investigated whether different doses of quetiapine (5, 10, and 30 mg/kg, oral gavage) administered to C57BL6/N mice could produce an anxiolytic effect in the Vogel conflict test, a classical model of anxiety, and whether or not the selective 5HT1A antagonist WAY100635 (0.1 mg/kg, subcutaneously) might prevent such an effect. Our results show that 10 mg/kg quetiapine exhibits an anxiolytic effect, that is, at least in part, 5HT1A-mediated, because it is completely eliminated by WAY100635.

Second-generation antipsychotics for major depressive disorder and dysthymia

BACKGROUND

Major depressive disorder (MDD) is a common condition with a lifetime prevalence of 15% to 18%, which leads to considerable suffering and disability. Some antipsychotics have been reported to induce remission in major depression, when added to an antidepressant.

OBJECTIVES

To evaluate the effects of second-generation antipsychotic (SGA) drugs (alone or augmentation) compared with placebo or antidepressants for people with MDD or dysthymia.

SEARCH STRATEGY

The Cochrane Depression, Anxiety and Neurosis Group's controlled trial registers (CCDANCTR-Studies and CCDANCTR-References) were searched up to 21 July 2010. The author team ran complementary searches on clinicaltrials.gov and contacted key authors and drug companies.

SELECTION CRITERIA

We included all randomised, double-blind trials comparing oral SGA treatment (alone or augmentation) with other forms of pharmaceutical treatment or placebo in people with MDD or dysthymia.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated the odds ratio (OR) and 95% confidence interval (CI) on an intention-to-treat basis, and for continuous data the mean difference (MD), based on a random-effects model. We presented each comparison separately; we did not perform a pooled data analysis.

MAIN RESULTS

We included 28 trials with 8487 participants on five SGAs: amisulpride, aripiprazole, olanzapine, quetiapine and risperidone.Three studies (1092 participants) provided data on aripiprazole augmentation in MDD. All efficacy data (response n = 1092, three RCTs, OR 0.48; 95% CI 0.37 to 0.63), (MADRS n = 1077, three RCTs, MD -3.04; 95% CI -4.09 to -2) indicated a benefit for aripiprazole but  more side effects (weight gain, EPS) .Seven trials (1754 participants) reported data on olanzapine. Compared to placebo fewer people discontinued treatment due to inefficacy; compared to antidepressants there were no efficacy differences, olanzapine augmentation showed symptom reduction (MADRS n = 808, five RCTs, MD -2.84; 95% CI -5.48 to -0.20), but also more weight or prolactin increase.Quetiapine data are based on seven trials (3414 participants). Compared to placebo, quetiapine monotherapy (response n = 1342, three RCTs, OR 0.52; 95% CI 0.41 to 0.66) and quetiapine augmentation (response n = 937, two RCTs, OR 0.68; 95% CI 0.52 to 0.90) showed symptom reduction, but quetiapine induced more sedation.Four trials (637 participants) presented data on risperidone augmentation, response data were better for risperidone (n = 371, two RCTs, OR 0.57; 95% CI 0.36 to 0.89) but augmentation showed more prolactin increase and weight gain.Five studies (1313 participants) presented data on amisulpride treatment for dysthymia. There were some beneficial effects compared to placebo or antidepressants but tolerability was worse.

AUTHORS' CONCLUSIONS

Quetiapine was more effective than placebo treatment. Aripiprazole and quetiapine and partly also olanzapine and risperidone augmentation showed beneficial effects compared to placebo. Some evidence indicated beneficial effects of low-dose amisulpride for dysthymic people. Most SGAs showed worse tolerability.

Second-generation antipsychotics for obsessive compulsive disorder

BACKGROUND

Obsessive compulsive disorder (OCD) is a psychiatric disorder which has been shown to affect 2 to 3.5% of people during their lifetimes. Inadequate response occurs in 40% to 60% of people that are prescribed first line pharmaceutical treatments (selective serotonin reuptake inhibitors (SSRIs)). To date not much is known about the efficacy and adverse effects of second-generation antipsychotic drugs (SGAs) in people suffering from OCD.

OBJECTIVES

To evaluate the effects of SGAs (monotherapy or add on) compared with placebo or other forms of pharmaceutical treatment for people with OCD.

SEARCH STRATEGY

The Cochrane Depression, Anxiety and Neurosis Group's controlled trial registers (CCDANCTR-Studies and CCDANCTR-References) were searched up to 21 July 2010. The author team ran complementary searches on ClinicalTrials.gov and contacted key authors and drug companies.

SELECTION CRITERIA

We included double-blind randomised controlled trials (RCTs) comparing oral SGAs (monotherapy or add on) in adults with other forms of pharmaceutical treatment or placebo in people with primary OCD.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated the odds ratio (OR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD), again based on a random-effects model.

MAIN RESULTS

We included 11 RCTs with 396 participants on three SGAs. All trials investigated the effects of adding these SGAs to antidepressants (usually SSRIs). The duration of all trials was less than six months. Only 13% of the participants left the trials early. Most trials were limited in terms of quality aspects.Two trials examined olanzapine and found no difference in the primary outcome (response to treatment) and most other efficacy-related outcomes but it was associated with more weight gain than monotherapy with antidepressants.Quetiapine combined with antidepressants was also not any more efficacious than placebo combined with antidepressants in terms of the primary outcome, but there was a significant superiority in the mean Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score at endpoint (MD -2.28, 95% CI -4.05 to -0.52). There were also some beneficial effects of quetiapine in terms of anxiety or depressive symptoms.Risperidone was more efficacious than placebo in terms of the primary outcome (number of participants without a significant response) (OR 0.17, 95% CI 0.04 to 0.66) and in the reduction of anxiety and depression (MD -7.60, 95% CI -12.37 to -2.83). 

AUTHORS' CONCLUSIONS

The available data of the effects of olanzapine in OCD are too limited to draw any conclusions. There is some evidence that adding quetiapine or risperidone to antidepressants increases efficacy, but this must be weighed against less tolerability and limited data.

Second-generation antipsychotics for anxiety disorders

BACKGROUND

Anxiety disorders are common and disabling conditions, with a lifetime prevalence of 17% in the general population. Due to high rates of treatment resistance, there is interest in new pharmacological treatment options such as second-generation antipsychotics.

OBJECTIVES

To evaluate the efficacy and tolerability of second-generation antipsychotics as monotherapy or adjunctive treatment for people with anxiety disorders.

SEARCH STRATEGY

The Cochrane Depression, Anxiety and Neurosis Group's controlled trial registers (CCDANCTR-Studies and CCDANCTR-References) were searched up to 21 July 2010. The author team ran complementary searches on ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised trials (RCTs) comparing second-generation antipsychotic drugs with placebo, benzodiazepines, pregabalin or antidepressants. Participants were people with generalised anxiety disorder, panic disorder and specific phobias including social phobia.

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently. For dichotomous data we calculated odds ratios (OR) and their 95% confidence intervals (CI). For continuous data we calculated mean differences (MD) based on a random-effects model.

MAIN RESULTS

The review currently includes eleven RCTs with 4144 participants on three second-generation antipsychotics (olanzapine, quetiapine, risperidone). Nine studies investigated the effects of second-generation antipsychotics in generalised anxiety disorder, only two studies investigated the effects in social phobia. There were no studies on panic disorder or any other primary anxiety disorder.Seven studies investigated the effects of quetiapine. Participants with generalised anxiety disorder responded significantly better to quetiapine than to placebo (4 RCTs, N = 2265, OR = 2.21, 95% CI 1.10 to 4.45). However, they were more likely to drop out due to adverse events, to gain weight, to suffer from sedation or to suffer from extrapyramidal side effects. When quetiapine was compared with antidepressants, there was no significant difference in efficacy-related outcomes, but more participants in the quetiapine groups dropped out due to adverse events, gained weight and feeling sedated. Only two very small studies with a total of 36 participants examined olanzapine and found no difference in response to treatment. Two trials compared adjunctive treatment with risperidone with placebo and found no difference in response to treatment.

AUTHORS' CONCLUSIONS

We identified eligible trials on quetiapine, risperidone and olanzapine. The available data on olanzapine and risperidone are too limited to draw any conclusions. Monotherapy with quetiapine seems to be efficacious in reducing symptoms of generalised anxiety disorder and this effect may be similar to that of antidepressants. However, quetiapine's efficacy must be weighed against its lower tolerability.

Prolonged toxicity in a 2-year-old after accidental ingestion of aripiprazole

Aripiprazole (Abilify), or 7-{4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy}-3,4-dihydro-2(1H)-quinolone, is a novel atypical antipsychotic possessing a long half-life. Although not a Food and Drug Administration-approved indication, low-dose aripiprazole is used to treat pediatric psychiatric conditions. Data regarding toxicity of low-dose aripiprazole ingestions in children are limited. We report the case of an accidental ingestion of two 5-mg aripiprazole tablets by a 2-year-old girl with a measured drug level of 160 ng/mL approximately 34 hours after ingestion. She exhibited marked lethargy, tremor, and tachycardia persisting over 72 hours. Emergency physicians, pediatricians, and psychiatrists should be aware of the potential for significant and prolonged toxicity in children even with relatively small-dose aripiprazole exposures.

Quetiapine in relapse prevention in alcoholics suffering from craving and affective symptoms: a case series

PURPOSE

Quetiapine is a novel antipsychotic, which is efficacious in the treatment of positive and negative symptoms in schizophrenia. Research has shown that atypical antipsychotic also reduce the craving and consumption for stimulants and alcohol. Due to Quetiapine's particulars and the promising receptor profile concerning addiction medicine, we set out to examine the tolerability and efficacy concerning relapse prevention of withdrawn alcoholics suffering from craving and affective symptoms.

SUBJECTS AND METHODS

Our case observations attempted to evaluate nine alcoholics after withdrawal suffering from persisting craving, sleep disorder, excitement, depressive symptoms or anxiety symptoms. The patients were treated with quetiapine as relapse prevention and we followed them up in our outpatient clinic.

RESULTS

Eight out of nine patients were abstinent under quetiapine over a period of 2-7 months. One of these patients relapsed after he stopped taking the preparation at his own initiative after 10 weeks. The ninth patient stopped taking the preparation immediately because of swollen nasal mucosae. All target symptoms disappeared in the patients after an average of (mean+/-S.D.) 24.5+/-18.1 days. The overall tolerability was considered to be very good; however, initial sleepiness appeared in four patients.

CONCLUSION

Although uncontrolled case observations can only be interpreted with caution quetiapine seems to deserve further investigation and may hold the potential for preventing alcohol relapse in alcoholics suffering from additional above-mentioned symptoms.

Discovery of new tetracyclic tetrahydrofuran derivatives as potential broad-spectrum psychotropic agents

A series of novel tetracyclic tetrahydrofuran derivatives was prepared and evaluated for its potential psychotropic properties. In vitro affinities for multiple dopaminergic, serotonergic, alpha-adrenergic, and histamine receptors and for the norepinephrine transporter as well as the ED(50) values obtained in some in vivo assays for antipsychotic, anxiolytic, and antidepressant potential are reported. Compounds (-)-1, (-)-8d, and (+)-8d have been identified as potential broad-spectrum psychotropic agents.

Aripiprazole: a novel atypical antipsychotic drug with a uniquely robust pharmacology

Aripiprazole (Abilify) is an atypical antipsychotic drug that has been recently introduced for clinical use in the treatment of schizophrenia. Aripiprazole has a unique pharmacologic profile that includes partial agonism at several G-protein coupled receptors (GPCRs) [especially dopamine (D2) and 5-HT1A] and antagonistic action at others (especially 5-HT2A). Clinical trials indicate that aripiprazole is effective in treating the positive and negative symptoms of schizophrenia. In short-term studies rapid onset of action (within one week) has been demonstrated. Preliminary data indicate that aripiprazole may also be effective in the treatment of manic symptoms of bipolar disorder. At recommended doses, aripiprazole appears to be safe and well tolerated in most adult patients with schizophrenia and schizoaffective disorder. There is only limited information available on the use of aripiprazole in children and adolescents, and pilot data suggest that a revised dosing strategy, based on weight, is indicated in this population. In the long-term studies, the use of aripiprazole was associated with continued efficacy, good compliance and increased time-to-relapse. Aripiprazole represents the first functionally selective atypical antipsychotic drug.

Atypicality of atypical antipsychotics

OBJECTIVE

To review the current definition of atypicality, discuss the unique features of each atypical antipsychotic, and determine whether the available drugs in this class really meet the classical definition of atypicality.

DATA SOURCES

A PubMed search was conducted to identify literature on the subject of this review, supported by additional articles based on the author's clinical knowledge and experience.

STUDY SELECTION AND DATA EXTRACTION

Relevant references were extracted and summarized in order to meet the objective of the article.

DATA SYNTHESIS

Atypical antipsychotics are considered a major advance over conventional antipsychotics, primarily because they offer effective treatment alternatives that are relatively free of extrapyramidal symptoms. In fact, the term atypicality was originally used to describe antipsychotic agents with a minimal risk of causing extrapyramidal symptoms. However, over the years the definition has been modified such that there is currently no consensus on a true definition of atypicality for these agents. Each of the atypical antipsychotics (clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole) commercially available in the United States is unique in terms of its pharmacologic profile, differing with respect to receptor-binding affinity, mechanism of action, and adverse events. Of the available atypical antipsychotics, clozapine and quetiapine have shown the lowest propensity to cause extrapyramidal symptoms. Although the risk of extra-pyramidal symptoms is lower with risperidone and olanzapine than with conventional antipsychotics, risk increases with dose escalation. Data for ziprasidone indicate that the risk of extrapyramidal symptoms may be similar to that of risperidone and olanzapine. There is a concern of akathisia with aripiprazole; however, more experience with this agent is needed before definitive conclusions are made.

CONCLUSION

If the definition of "atypical" antipsychotic is considered to be freedom from extrapyramidal symptoms, then, based on a comprehensive review of available data and clinical experience, clozapine and quetiapine appear to be the only true atypicals.