Atypical antipsychotics: matching receptor profile to individual patient's clinical profile

Early-life risperidone alters locomotor responses to apomorphine and quinpirole in adulthood

An escalating trend of antipsychotic drug use in children with ADHD, disruptive behavior disorder, or mood disorders has raised concerns about the impact of these drugs on brain development. Since antipsychotics chiefly target dopamine receptors, it is important to assay the function of these receptors after early-life antipsychotic administration. Using rats as a model, we examined the effects of early-life risperidone, the most prescribed antipsychotic drug in children, on locomotor responses to the dopamine D1/D2 receptor agonist, apomorphine, and the D2/D3 receptor agonist, quinpirole. Female and male Long-Evans rats received daily subcutaneous injections of risperidone (1.0 and 3.0 mg/kg) or vehicle from postnatal day 14-42. Locomotor responses to one of three doses (0.03, 0.1, and 0.3 mg/kg) of apomorphine or quinpirole were tested once a week for four weeks beginning on postnatal day 76 and 147 for each respective drug. The locomotor activity elicited by the two lower doses of apomorphine was significantly greater in adult rats, especially females, administered risperidone early in life. Adult rats administered risperidone early in life also showed more locomotor activity after the low dose of quinpirole. Overall, female rats were more sensitive to the locomotor effects of each agonist. In a separate group of rats administered risperidone early in life, autoradiography of forebrain D2 receptors at postnatal day 62 revealed a modest increase in D2 receptor density in the medial caudate. These results provide evidence that early-life risperidone administration can produce long-lasting changes in dopamine receptor function and density.

Avoidant restrictive food intake disorder: recent advances in neurobiology and treatment

Avoidant restrictive food intake disorder (ARFID) is an eating disorder characterized by persistent insufficient nutritional and/or energy intake. ARFID, before referred to as "selective eating disorder", was introduced recently in the DSM-5 as a replacement for and expansion of the previous diagnosis. Individuals with ARFID may limit food variety and intake due to avoidance based on the sensory characteristics of the food or related to any adverse consequences of eating without the intention of losing weight and concerns of body image. The limited understanding of avoidant and restrictive eating poses challenges to effective treatment and management, impacting directly on the growth and development of children and adolescents. The ARFID neurobiological concept has not yet been clearly defined to clinical practice for nutritionists, thereby hindering screening and impeding the development of treatment recommendations. This narrative review provide useful practical information to consult the pathophysiology, the neurobiology, the clinical features, the assessment and the treatment for healthcare professionals seeking to enhance their clinical knowledge and management of this disorder.

Seventy Years of Antipsychotic Development: A Critical Review

Since the mid-1950s discovery of the first effective antipsychotic medications (APM), we have only been able to improve the tolerability but not the overall efficacy of currently available APMs, as reflected by effectiveness trials in Europe and the United States. This inability to develop more effective APMs is attributable to multiple factors, including failure to create and use assessment tools to assess core symptom domains in schizophrenia, move beyond the dopaminergic hypothesis and to develop "me too" drugs, imposing ill-defined research domain criteria, and lacking federal funding for clinical trials. The classification of APMs is also confusing, including second-generation, partial agonists, and multimodal APMs in the same class of APMs, despite significant differences in their mechanisms of action. Other factors stagnating drug development include inadequate sample sizes to address heterogeneity, lack of statistical measures correlating with clinical significance, using the atheoretical basis of psychiatric diagnoses, failure to control placebo response, and high cost of newer and perhaps more tolerable APMs. Furthermore, there has been a failure to develop early predictors of antipsychotic response and various tools to optimize an APM response. Finally, some mental health providers are also responsible for the suboptimal use of APMs, by using excessive maintenance doses, often with irrational polypharmacy, further compromising effectiveness and medication adherence. However, some bright spots in antipsychotic development include improved tolerability of APMs and long-acting injectables to address the high prevalence of medication nonadherence. This review critically reviews 70 years of antipsychotic development, the reasons behind the failure to develop more effective APMs, and suggestions for future direction.

Comorbidities in Youth with Bipolar Disorder: Clinical Features and Pharmacological Management

BACKGROUND

Bipolar Disorder (BD) is a highly comorbid condition, and rates of cooccurring disorders are even higher in youth. Comorbid disorders strongly affect clinical presentation, natural course, prognosis, and treatment.

METHODS

This review focuses on the clinical and treatment implications of the comorbidity between BD and Attention-Deficit/Hyperactivity Disorder, disruptive behavior disorders (Oppositional Defiant Disorder and/or Conduct Disorder), alcohol and substance use disorders, Autism Spectrum Disorder, anxiety disorders, Obsessive-Compulsive Disorder, and eating disorders.

RESULTS

These associations define specific conditions which are not simply a sum of different clinical pictures, but occur as distinct and complex combinations with specific developmental pathways over time and selective therapeutic requirements. Pharmacological treatments can improve these clinical pictures by addressing the comorbid conditions, though the same treatments may also worsen BD by inducing manic or depressive switches.

CONCLUSION

The timely identification of BD comorbidities may have relevant clinical implications in terms of symptomatology, course, treatment and outcome. Specific studies addressing the pharmacological management of BD and comorbidities are still scarce, and information is particularly lacking in children and adolescents; for this reason, the present review also included studies conducted on adult samples. Developmentally-sensitive controlled clinical trials are thus warranted to improve the prognosis of these highly complex patients, requiring timely and finely personalized therapies.

Effect of quetiapine on inflammation and immunity: a systematic review

INTRODUCTION

Knowledge about the neurobiology of psychiatric disorders is increasing in the last decades and evidence from literature suggests a central role for immuno-inflammatory mechanisms in these illnesses. The antipsychotic quetiapine acts on dopamine and serotonin signalling and well-established evidence demonstrates that these neurotransmitters can modulate immune functions in healthy and diseased conditions. Starting from this perspective, in the last few decades, a number of studies attempted to identify quetiapine effects on immune functions in order to highlight a possible additional effect of this drug in psychotic diseases, although no conclusive results were obtained.

METHODS

We critically reviewed preclinical and clinical studies evaluating quetiapine effects on immune systems, suggesting strategies for future work in this field.

RESULTS

Computerised search, in PubMed and Embase databases, was performed in March 2020: 120 studies were identified but only 29 relevant papers were selected for detailed review.

CONCLUSION

Despite some interesting preliminary findings about anti-inflammatory effects of quetiapine, mainly supported by preclinical studies, it is possible to conclude further studies are needed to investigate the immunomodulatory effects of this drug and achieve a better understanding of its relevance on clinical outcomes to finally identify new therapeutic approaches in psychiatric treatment.KeypointsMounting evidence points to a role for immuno-inflammatory mechanisms in psychiatric disorders.Quetiapine (QUE) acts on catecholamine (dopamine and norepinephrine) and serotonin signalling.The immunomodulatory effects of catecholamines are well established.Treatment with QUE in psychiatric disorders could leverage immunomodulatory effects.QUE unclear role in immune function modulation suggests future work.

Switching Clozapine to Cariprazine in Three Patients with Persistent Symptoms of Schizophrenia: A Case Series

Despite many available treatments for schizophrenia, several unmet needs persist in treating individuals with this disorder, and the response rate to first-line antipsychotics remains relatively low. Clozapine has shown efficacy in treating schizophrenia patients who failed to respond to previous antipsychotics. However, side effects and the need for routine blood tests have limited its use as a first-line treatment. Cariprazine is a D₂/D₃ partial agonist antipsychotic with a mechanism of action that differs from other antipsychotics due to its higher affinity for D₃ receptors. Several trials have demonstrated the efficacy of cariprazine on positive and negative symptoms of schizophrenia and have shown that it is a well-tolerated treatment. In this series, we present 3 cases of patients diagnosed with schizophrenia who were initially under treatment with clozapine. Despite some initial improvement, the patients showed persisting positive and negative symptoms or developed limiting side effects while in treatment with clozapine. Cariprazine treatment was titrated concurrently with clozapine tapering until its discontinuation. Significant improvement in both positive and negative symptoms was observed up to 14 months after starting cariprazine, and resolution of side effects was reported in all cases. Our case series supports cariprazine as an effective treatment for positive and negative symptoms in patients who failed to adequately respond or poorly tolerated treatment with clozapine, as well as a potential treatment in dual disorders, specifically psychotic disorders and cocaine use disorder.

Therapeutic potential of TAK-071, a muscarinic M1 receptor positive allosteric modulator with low cooperativity, for the treatment of cognitive deficits and negative symptoms associated with schizophrenia

The selective activation of the muscarinic M1 receptor (M1R) may be a promising approach for treating cognitive impairment associated with cholinergic dysfunction. We previously reported that low cooperativity (α-value) is associated with a favorable cholinergic side effect profile of M1R positive allosteric modulators (M1 PAMs), as well as being a crucial factor for the cognitive improvement observed after combining M1 PAMs with donepezil, in rodents. In this study, we preclinically characterized TAK-071, a novel M1 PAM with low cooperativity (α-value = 199), as a new therapy for schizophrenia. We tested TAK-071 in the offspring of polyriboinosinic-polyribocytidylic acid-treated dams, which is a maternal immune activation model of schizophrenia. TAK-071 improved sociability deficits and working memory in this model. In a genetic mouse model of schizophrenia, miR-137 transgenic (Tg) mice, TAK-071 improved deficits in working memory, recognition memory, sociability, and sensorimotor gating. Patients with schizophrenia usually take several antipsychotics to treat positive symptoms. Thus, we also investigated the combined effects of TAK-071 with currently prescribed antipsychotics. Among the 10 antipsychotics tested, only olanzapine and quetiapine showed M1R antagonistic effects, which were counteracted by TAK-071 at possible effective concentrations for cognitive improvement in vitro. Moreover, haloperidol did not affect the ability of TAK-071 to improve working memory in miR-137 Tg mice, suggesting a low risk of losing efficacy when combined with dopamine D2 receptor antagonists. In conclusion, TAK-071 can exert beneficial effects on social behavior and cognitive function and could be a new therapy for schizophrenia.

Cariprazine, A Broad-Spectrum Antipsychotic for the Treatment of Schizophrenia: Pharmacology, Efficacy, and Safety

Schizophrenia is characterized by positive, negative, cognitive, and affective symptoms. Antipsychotic medications, which work by blocking the dopamine D₂ receptor, are the foundation of pharmacotherapy for schizophrenia to control positive symptoms. Cariprazine is a dopamine D₃ receptor-preferring D₃/D₂ partial agonist antipsychotic that is approved for the treatment of schizophrenia (USA and European Union [EU]) and manic and depressive episodes associated with bipolar I disorder (USA). Partial agonist agents have a lower intrinsic activity at receptors than full agonists, so they act as either functional agonists or functional antagonists depending on the surrounding neurotransmitter environment. Beyond efficacy against positive symptoms, the unique D₃-preferring partial agonist pharmacology of cariprazine suggests potential advantages against negative symptoms, and cognitive and functional impairment, which are challenging to treat. The efficacy and safety of cariprazine in adult patients with schizophrenia have been demonstrated in four short-term randomized, double-blind, placebo-controlled clinical trials, two long-term open-label studies, one relapse prevention study, and one prospective negative symptom study versus the active comparator risperidone. Additional post hoc investigations have supported efficacy across individual symptoms and domains in schizophrenia, as well as in diverse areas of interest including cognition, functioning, negative symptoms, hostility, and global well-being. This comprehensive review of cariprazine summarizes its pharmacologic profile, clinical trial evidence, and post hoc investigations. Collective evidence suggests that the pharmacology of cariprazine may offer broad-spectrum efficacy advantages for patients with schizophrenia, including effects against difficult-to-treat negative and cognitive symptoms, as well as functional improvements. Cariprazine was generally safe and well tolerated in patients with short- and long-term exposure and no new safety concerns were associated with longer-duration treatment.

Trial registration ClinicalTrials.gov identifiers, NCT00404573, NCT00694707, NCT01104766, NCT01104779, NCT01412060, NCT00839852, NCT01104792.

Altered expression of the DISC1 gene in peripheral blood of patients with schizophrenia

Background

Schizophrenia is a severe, heritable, and refractory psychiatric disorder. Several studies have shown that the disrupted in schizophrenia 1 (DISC1) gene is closely associated with schizophrenia by its role in neuronal morphology, synaptic function, brain development, and dopamine homeostasis etc. This study intended to investigate the expression levels of DISC1 gene in schizophrenia patients compared with healthy controls, and the expression variation of DISC1 gene before and after antipsychotic treatment in schizophrenia patients.

Methods

In this study, we compared DISC1 expression levels in blood of 48 healthy controls, and 32 schizophrenia patients before and after 12 weeks of antipsychotic treatment using real-time quantitative PCR (RT-qPCR) analysis.

Results

The expression levels of DISC1 gene in peripheral blood mononuclear cells of schizophrenia patients before antipsychotic treatment were higher than those in healthy controls (P < 0.01); whereas after antipsychotic treatment, the expression levels of DISC1 gene in peripheral blood mononuclear cells of schizophrenia patients still remained increased (P < 0.01).

Conclusions

Our study provided further support for the involvement of DISC1 in the development of schizophrenia.

Schizophrenia, antipsychotics and diabetes: Genetic aspects

The relatively high comorbidity of type 2 diabetes and schizophrenia may suggest a shared biological susceptibility to these twoconditions. Family studies have demonstrated an increased risk of diabetes in unaffected relatives of patients with schizophrenia, consistent with a heritable susceptibility trait. Linkage analyses have identified several loci that are associated with schizophrenia and some of these, notably those on chromosomes 2p22.1-p13.2 and 6g21-824.1 have also been observed in linkage studies in type 2 diabetes. In addition, the dopamine D5 receptor on chromosome 5 and the tyrosine hydroxylase gene on chromosome 11 have both been suggested as candidate genes in schizophrenia and may also be implicated in susceptibility to poor glycaemic control. In addition, an increased rate of type II diabetes has been observed in some patients treated with antipsychotics. Potential neurochemical substrates of this effect include the histamine H1 receptor, the 5-HT2C serotonin receptor or the β3 adrenoreceptor. However, the search for a genetic basis to the association between diabetes and schizophrenia is still in its infancy, and much further work needs to be performed, including the systematic screening of all confirmed susceptibility loci and quantitative trait locus mapping of glycaemic control.

The effect of high vs. low dose lurasidone on eye movement biomarkers of prefrontal abilities in treatment-resistant schizophrenia

OBJECTIVE

Eye movement (EM) measures can serve as biomarkers to evaluate pharmacological effects on brain systems involved in cognition. In recent onset schizophrenia, antipsychotic treatment can improve attentional control on the antisaccade task and exacerbate working memory impairment on the memory guided saccade task; effects in treatment-resistant schizophrenia (TRS) are less clear. This study evaluated the effects of high versus low dose lurasidone on EM performance in TRS.

METHODS

TRS patients completed EM testing: 1) at baseline, on existing medication regimen (n = 42), 2) after 6 weeks of low dose (80 mg) lurasidone (n = 38), 3) after 12 weeks following randomization to low (80 mg) or high dose (240 mg) lurasidone (n = 27), and 4) after 24 weeks of treatment (n = 23). EM testing included prosaccade, antisaccade, and memory guided saccade tasks.

RESULTS

Six weeks of lurasidone resulted in increased prosaccade saccade latency and reduced antisaccade errors, with no change in memory guided saccade accuracy. After randomization, prosaccade and antisaccade latencies increased in only the high dose group, with no change in antisaccade errors in both groups. Memory guided saccade error increased in the high dose group and remained stable in the low dose group.

CONCLUSION

Among TRS, stabilization on low dose lurasidone was associated with improved executive control of attention reflected by reduced antisaccade errors. High dose lurasidone resulted in prolonged speed of reflexive and executive shifts of attention and reduced spatial working memory relative to low dose. These findings indicate that EM measures are helpful biomarkers of dose-dependent antipsychotic treatment effects on executive cognitive abilities in TRS.

Altered expression of the CSMD1 gene in the peripheral blood of schizophrenia patients

BACKGROUND

Schizophrenia (SCZ) is a heritable, refractory, and devastating psychiatric disorder. Previous studies have shown that the variants of CUB and sushi multiple domains 1 (CSMD1) demonstrate significant genome-wide association with SCZ. However, few studies have been conducted on the effect of antipsychotics on the expression levels of CSMD1. This study explored whether a change occurs in the expression of the CSMD1 gene before and after antipsychotic treatment in SCZ patients.

METHODS

The study population comprised Han Chinese patients from eastern China, including 32 SCZ patients and 48 healthy controls. The expression of CSMD1 before and after treatment in the SCZ group and between the two groups was analyzed using real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

The expression levels of the CSMD1 gene in the peripheral blood mononuclear cells (PBMCs) of SCZ patients were lower than those in the healthy controls. The expression levels of the CSMD1 gene in the PBMCs of the SCZ patients after antipsychotic treatment were higher than those in the baseline SCZ patients (all P <  0.05).

CONCLUSIONS

Our results showed that the expression levels of CSMD1 are correlated with the development and treatment of SCZ, providing further evidence for the involvement of CSMD1 in SCZ.

Hospitalization risk in bipolar disorder patients treated with lurasidone versus other atypical antipsychotics

OBJECTIVE

This observational study compared the risk of hospitalization for patients with bipolar disorder when treated with lurasidone versus other oral atypical antipsychotics.

METHODS

This US commercial claims analysis (4 April 2010 through 24 September 2014) used the Optum Research Database to identify adult patients with bipolar disorder treated with oral atypical antipsychotics (N = 11,132). The first claim for an atypical antipsychotic defined the index date, with pre-index and post-index periods of 180 and 360 days, respectively. Every month of the post-index period was categorized as monotherapy treatment with lurasidone, aripiprazole, olanzapine, quetiapine, risperidone, ziprasidone, no/minimal treatment or other. Starting with the initial month of treatment, the risk of psychiatric or all-cause hospitalization in the subsequent month was examined based on treatment in the current month and pre-index covariates (age, gender, hospitalizations, emergency room visits, diagnoses for anxiety, alcohol abuse, substance abuse, hypertension, type 2 diabetes and obesity) and time-varying versions of the pre-index covariates using a marginal structural model.

RESULTS

After controlling for covariates, relative to lurasidone, the odds of psychiatric and all-cause hospitalization, respectively, were 2-3 times higher for olanzapine (odds ratio [OR] = 2.78, CI 1.09, 7.08, p = .032; OR = 3.20, CI 1.24, 8.26, p = .016), quetiapine (OR = 2.80, CI 1.13, 6.95, p = .026; OR = 3.23, CI 1.29, 8.11, p = .013), risperidone (OR = 2.50, CI 1.01, 6.21, p = .048; OR = 2.79, CI 1.11, 7.02, p = .029), aripiprazole (OR = 2.13, CI 0.87, 5.20, p = .097; OR = 2.57, CI 1.04, 6.37, p = .041) and ziprasidone (OR =2.31, CI 0.91, 5.85, p = .079; OR = 2.49, CI 0.97, 6.40, p = .058).

CONCLUSIONS

In this claims database analysis, lurasidone-treated patients with bipolar disorder had a significantly lower risk of psychiatric hospitalization compared to quetiapine, olanzapine and risperidone, but not aripiprazole or ziprasidone. Lurasidone-treated patients had a significantly lower risk of all-cause hospitalization compared to quetiapine, olanzapine, risperidone and aripiprazole, but not ziprasidone.

Asenapine Treatment in Pediatric Patients with Bipolar I Disorder or Schizophrenia: A Review

Asenapine, administered as a twice-daily (BID) sublingual tablet, is approved in the US as monotherapy for the acute treatment of manic and mixed episodes of bipolar I disorder in children and adolescents aged 10-17 years based on the positive results of one 3-week, double-blind, placebo-controlled study; the recommended dose is 2.5-10 mg BID. Although asenapine has been studied in pediatric patients with schizophrenia, it is not approved for this indication. Asenapine is not approved for pediatric use in bipolar I disorder or schizophrenia in other major markets. To inform clinicians treating psychiatric disorders in pediatric patients, we have summarized the neuropharmacology, pharmacokinetics, clinical trial experience, and clinical use of asenapine in pediatric patients. After rapid absorption through the oral mucosa, the pharmacokinetic profile of asenapine in pediatric patients is similar to that which is observed in adult patients, indicating that the recommended adult dosage does not need to be adjusted for pediatric use. Intake of food and water should be avoided for 10 min after administration. In clinical trials, asenapine was generally safe and well tolerated in pediatric patients with bipolar I disorder and schizophrenia. Serious adverse effects were generally related to worsening of the underlying psychiatric disorder. The most common treatment-emergent adverse events (TEAEs) in both indications were sedation and somnolence. Like some other second-generation antipsychotic agents, weight gain and changes in some metabolic parameters were noted; oral effects (e.g., oral hypoesthesia, dysgeusia, paresthesia) related to sublingual administration did not typically result in treatment discontinuation and were generally transient. Extrapyramidal symptom TEAEs occurred in ≥5% of asenapine-treated patients in the acute and long-term studies in bipolar I disorder and schizophrenia.

Lurasidone in the Treatment of Bipolar Depression: Systematic Review of Systematic Reviews

INTRODUCTION

A burgeoning number of systematic reviews considering lurasidone in the treatment of bipolar depression have occurred since its Food and Drug Administration extended approval in 2013. While a paucity of available quantitative evidence still precludes preliminary meta-analysis on the matter, the present quality assessment of systematic review of systematic reviews, nonetheless, aims at highlighting current essential information on the topic.

METHODS

Both published and unpublished systematic reviews about lurasidone mono- or adjunctive therapy in the treatment of bipolar depression were searched by two independent authors inquiring PubMed/Cochrane/Embase/Scopus from inception until October 2016.

RESULTS

Twelve included systematic reviews were of moderate-to-high quality and consistent in covering the handful of RCTs available to date, suggesting the promising efficacy, safety, and tolerability profile of lurasidone. Concordance on the drug profile seems to be corroborated by a steadily increasing number of convergent qualitative reports on the matter.

LIMITATIONS

Publication, sponsorship, language, citation, and measurement biases.

CONCLUSIONS

Despite being preliminary in nature, this overview stipulates the effectiveness of lurasidone in the acute treatment of Type I bipolar depression overall. As outlined by most of the reviewed evidence, recommendations for future research should include further controlled trials of extended duration.

Association between antipsychotic drug use and cataracts in patients with bipolar disorder: A population-based, nested case-control study

BACKGROUND

No previous study has focused on the association between use of antipsychotic drugs and the development of cataracts in patients with bipolar disorder (BD); hence, we aimed to examine this association in the present study.

METHODS

We conducted a retrospective nested case-control study using data from the National Health Insurance Database of Taiwan between 2000 and 2011. A total of 3292 BD patients, 1684 with cataracts and 1608 controls matched for age, sex, and index date, were included. Antipsychotic drug exposure was categorized by type of drug and duration of use. A conditional logistic regression analysis was used to analyze the association.

RESULTS

Among BD patients, we found significantly reduced odds ratio (OR) of cataract development among past (adjusted OR (AOR), 0.74; 95% confidence interval (CI), 0.62-0.89; p=0.001) and continuous users (AOR, 0.71; 95% CI, 0.59-0.85; p<0.001) of atypical antipsychotics. No association was found between the odds of cataract development and typical antipsychotics. Besides, concomitant use of antidepressants (AOR, 1.23; 95% CI, 1.06-1.43; p=0.007) and mood stabilizers (AOR, 1.23; 95% CI, 1.06-1.42; p=0.007) were associated with increased odds of cataract development.

LIMITATIONS

Some important contributors to cataract development such as family history of cataract, smoking and alcohol exposure could not be measured from the claims data and this may confound the results.

CONCLUSIONS

Reduced odds of cataract were found in patients with BD taking atypical antipsychotics. However, given that BD patients often have risk factors for developing cataract, regular ocular evaluations are recommended for those treated with antipsychotics drugs.

Antipsychotic inductors of brain hypothermia and torpor-like states: perspectives of application

Hypothermia and hypometabolism (hypometabothermia) normally observed during natural hibernation and torpor, allow animals to protect their body and brain against the damaging effects of adverse environment. A similar state of hypothermia can be achieved under artificial conditions through physical cooling or pharmacological effects directed at suppression of metabolism and the processes of thermoregulation. In these conditions called torpor-like states, the mammalian ability to recover from stroke, heart attack, and traumatic injuries greatly increases. Therefore, the development of therapeutic methods for different pathologies is a matter of great concern. With the discovery of the antipsychotic drug chlorpromazine in the 1950s of the last century, the first attempts to create a pharmacologically induced state of hibernation for therapeutic purposes were made. That was the beginning of numerous studies in animals and the broad use of therapeutic hypothermia in medicine. Over the last years, many new agents have been discovered which were capable of lowering the body temperature and inhibiting the metabolism. The psychotropic agents occupy a significant place among them, which, in our opinion, is not sufficiently recognized in the contemporary literature. In this review, we summarized the latest achievements related to the ability of modern antipsychotics to target specific receptors in the brain, responsible for the initiation of hypometabothermia.

The safety, efficacy and tolerability of Abilify Maintena for the treatment of schizophrenia

Relapse in schizophrenia has been associated with poor adherence to oral medication. A possible method to optimize medication adherence could be to switch patients from oral to depot medication. In this respect, aripiprazole long acting injectable (ALAI) significantly delayed time to impending relapse when compared with placebo (p < 0.0001), while ALAI was generally well tolerated during both short-term and long-term studies. A literature search, using PubMed was conducted to identify relevant publications. Available evidence suggests that ALAI may be a viable treatment option for patients with schizophrenia, but before it can be concluded whether or not all schizophrenia patients could benefit from a switch to depot formulations, several questions remain to be answered. Thus, there is a great need for randomized controlled trials comparing depot medications with their oral equivalents.

Use of aripiprazole for delirium in the elderly: a short review

The effects and tolerability of antipsychotics in delirium treatment remain controversial. Compared to other antipsychotics, aripiprazole differs in pharmacological activity because it exerts its effect as a dopamine D2 partial agonist. The guidelines of the American Psychiatric Association rank aripiprazole highly among antipsychotics with regard to safety, and this drug is likely to be useful for delirium treatment. Here, we reviewed the efficacy and safety of aripiprazole for delirium. The results of our literature review on the efficacy and safety of delirium treatments suggest that aripiprazole is an effective treatment option for delirium in the elderly. Aripiprazole is as effective as other antipsychotics in improving delirium symptoms, and it is safer because it is less likely to cause extrapyramidal symptoms, excessive sedation, and weight gain. However, these findings are based on only a few clinical studies of elderly patients with delirium. Therefore, further investigations are necessary.

Pharmacogenetics of second-generation antipsychotics

This review considers pharmacogenetics of the so called 'second-generation' antipsychotics. Findings for polymorphisms replicating in more than one study are emphasized and compared and contrasted with larger-scale candidate gene studies and genome-wide association study analyses. Variants in three types of genes are discussed: pharmacokinetic genes associated with drug metabolism and disposition, pharmacodynamic genes encoding drug targets, and pharmacotypic genes impacting disease presentation and subtype. Among pharmacokinetic markers, CYP2D6 metabolizer phenotype has clear clinical significance, as it impacts dosing considerations for aripiprazole, iloperidone and risperidone, and variants of the ABCB1 gene hold promise as biomarkers for dosing for olanzapine and clozapine. Among pharmacodynamic variants, the TaqIA1 allele of the DRD2 gene, the DRD3 (Ser9Gly) polymorphism, and the HTR2C -759C/T polymorphism have emerged as potential biomarkers for response and/or side effects. However, large-scale candidate gene studies and genome-wide association studies indicate that pharmacotypic genes may ultimately prove to be the richest source of biomarkers for response and side effect profiles for second-generation antipsychotics.

Lack of tolerable treatment options for patients with schizophrenia

PURPOSE

Atypical antipsychotics (AAs), an effective treatment for schizophrenia, have a range of pharmacologic properties leading to differences in tolerability as well as heterogeneity in treatment response. Individual patient characteristics must be considered when making treatment choices, especially from an adverse event (AE) or tolerability perspective. Despite the availability of numerous AAs, after appraising patient characteristics at the time of treatment selection, physicians may quickly run out of tolerable treatment options.

PATIENTS AND METHODS

AE risk factors, defined as having either a prior history of an AE or a risk factor for that AE, were determined for Medicaid-insured and Commercially insured patients using database analysis. Patients receiving AA treatment between January 1, 2010 and December 31, 2012 defined the index date of first observed AA prescription during this period. Nine AAs were evaluated for association with AE risk factors as informed by drug prescribing information from the different manufacturers and published meta-analyses. The proportion of patients with pre-index AE risk factors prescribed an AA associated with that risk factor was then determined.

RESULTS

A high proportion of patients (>80%) were prescribed an AA associated with extrapyramidal symptoms or akathisia despite experiencing extrapyramidal symptoms or akathisia prior to AA treatment initiation. Similar trends were observed among patients with diabetes (>60%) and obesity (>40%). From the nine treatment options available, the number of optimal choices for individual patient segments were limited based on their prior history, including those with cardiometabolic and cardiovascular comorbidities (four); experiencing prolactin elevation-related problems (seven); needing to avoid excessive sedation (four); or at risk of extrapyramidal symptoms or akathisia (two). Options were then further restricted among patients in more than one segment when multiple pre-index AE risk factors were combined.

CONCLUSION

When combining patient risk profile with antipsychotic AE profile, physicians may quickly run out of tolerable treatment options for individual patients, despite the availability of many AAs, suggesting a need for additional treatment options with better tolerability and without compromising efficacy.

Profile of aripiprazole in the treatment of bipolar disorder in children and adolescents

Bipolar disorder is a pernicious illness. Compared with the later-onset form, early onset bipolar disorder is associated with worse psychosocial outcomes, and is characterized by rapid cycling and increased risks of substance abuse and suicide attempts. Controlling mood episodes and preventing relapse in this group of pediatric patients requires careful treatment. Here, we review the effectiveness of aripiprazole for bipolar disorder in children and adolescents, with discussion of this drug's unique pharmacological profile and various clinical study outcomes. Aripiprazole acts as a serotonin 5-HT2A receptor antagonist, as well as a partial agonist of the serotonin 5-HT1A and dopamine D2 receptors. It can be safely used in children and adolescents, as it is highly tolerated and shows lower rates of the side effects typically observed with other antipsychotic drugs, including sedation, weight gain, hyperprolactinemia, and extrapyramidal syndrome. The presently reviewed randomized controlled trials (RCTs) and non-RCTs generally reported aripiprazole to be effective and well-tolerated in children and adolescents with bipolar disorder. However, due to the limited number of RCTs, the present conclusions must be evaluated cautiously. Furthermore, aripiprazole cannot yet be considered a preferred treatment for children and adolescents with bipolar disorder, as there is not yet evidence that aripiprazole shows greater efficacy compared to other second-generation antipsychotics. Additional data are needed from future head-to-head comparison studies.

Comparative mortality risks of antipsychotic medications in community-dwelling older adults

BACKGROUND

All antipsychotic medications carry warnings of increased mortality for older adults, but little is known about comparative mortality risks between individual agents.

AIMS

To estimate the comparative mortality risks of commonly prescribed antipsychotic agents in older people living in the community.

METHOD

A retrospective, claims-based cohort study was conducted of people over 65 years old living in the community who had been newly prescribed risperidone, olanzapine, quetiapine, haloperidol, aripiprazole or ziprasidone (n = 136 393). Propensity score-adjusted Cox proportional hazards models assessed the 180-day mortality risk of each antipsychotic compared with risperidone.

RESULTS

Risperidone, olanzapine and haloperidol showed a dose-response relation in mortality risk. After controlling for propensity score and dose, mortality risk was found to be increased for haloperidol (hazard ratio (HR) = 1.18, 95% CI 1.06-1.33) and decreased for quetiapine (HR = 0.81, 95% CI 0.73-0.89) and olanzapine (HR = 0.82, 95% CI 0.74-0.90).

CONCLUSIONS

Significant variation in mortality risk across commonly prescribed antipsychotics suggests that antipsychotic selection and dosing may affect survival of older people living in the community.

Role of atypical antipsychotics in the treatment of generalized anxiety disorder

Evidence-based treatment approaches for generalized anxiety disorder (GAD) comprise psychotherapy, pharmacotherapy, or a combination of the two. First-line pharmacotherapy agents include selective serotonin reuptake inhibitors, selective serotonin-norepinephrine reuptake inhibitors, and, in certain European guidelines, pregabalin, which gained European Commission approval. Although short- and long-term efficacy have been established for these agents in controlled trials, response rates of 60-70 % are insufficient, remission rates are relatively modest, and relapse rates considerable. Moreover, questions increasingly arise regarding tolerability and side-effect profiles. As an alternative, antipsychotics have long been of interest for the treatment of anxiety disorders, but investigation had been tempered by their potential for irreversible side effects. With the improved side-effect profiles of atypical antipsychotics, these agents are increasingly being investigated across Axis I disorders. Atypical antipsychotics such as quetiapine, aripiprazole, olanzapine, and risperidone have been shown to be helpful in addressing a range of anxiety and depressive symptoms in individuals with schizophrenia and schizoaffective disorders, and have since been used in the treatment of a range of mood and anxiety disorders. In this article, we review the efficacy and tolerability of atypical antipsychotics as adjunctive therapy and/or monotherapy for individuals with GAD, a currently off-label indication. The most evidence has accumulated for quetiapine. Findings suggest that approximately 50 % of participants tolerate the side effects, most commonly sedation and fatigue. Among this subset, those who continue treatment demonstrate significant reductions in anxiety when used as adjunctive therapy or monotherapy. The appropriateness of the use of antipsychotics in the treatment of GAD is discussed.

Asenapine review, part I: chemistry, receptor affinity profile, pharmacokinetics and metabolism

INTRODUCTION

Asenapine is a second-generation (atypical) antipsychotic currently marketed for the treatment of schizophrenia and bipolar mania/mixed episodes.

AREAS COVERED

The purpose of this review is to describe the chemistry, pharmacodynamics, and pharmacokinetics of asenapine.

EXPERT OPINION

Asenapine has a complex pharmacodynamic profile with affinities at multiple dopamine, serotonin, histamine, and α-adrenergic receptors, all at which asenapine functions as an antagonist. Sublingual asenapine tablets are absorbed in the oral mucosa, with a Tmax occurring between 30 and 90 min. Terminal half-life is approximately 24 h. Asenapine has multiple inactive metabolites, produced via direct glucuronidation (primarily via UGT1A4), demethylation, and oxidative metabolism (primarily via CYP1A2). Hepatic and renal routes contribute approximately equally to the elimination of asenapine and its metabolites. Two notable drug-drug interactions are evident: asenapine (an inhibitor of CYP2D6) can increase plasma levels of paroxetine, and fluvoxamine (a CYP1A2 inhibitor) can increase plasma levels of asenapine. Caution is required when coadministering asenapine with drugs that are both substrates and inhibitors of CYP2D6.

Olanzapine: a 5-year perspective

Olanzapine is a novel antipsychotic, approved for the acute and maintenance treatment of schizophrenia and bipolar I disorder. Despite the publicity regarding reported adverse events with the novel antipsychotics, such as weight gain and Type II diabetes mellitus, olanzapine remains a useful and important medicine. It is a selective monoaminergic antagonist with high-affinity binding to a number of receptors thought to be implicated in some psychotic and mood symptoms. The complex pharmacology of olanzapine has lead to studies exploring its use in treating substance abuse, aggression/violence, borderline personality disorder, schizotypal personality disorder, obsessive-compulsive disorder and as a neuroprotective agent in schizophrenia. As the pharmacology of olanzapine and other novel antipsychotics becomes better understood, future effective treatment strategies are likely to match an individual's genetic makeup and receptor profiles to the most compatible agent.

Differential cognitive performances between schizophrenic responders and non-responders to antipsychotics: correlation with course of the illness, psychopathology, attitude to the treatment and antipsychotics doses

Multiple lines of evidence demonstrate that schizophrenia patients may perform worse than normal controls in several cognitive tasks. However, little is known on putative differences in cognitive functioning between schizophrenia patients responding to antipsychotics and those resistant to the treatment. In this cross-sectional study, 63 subjects (41 schizophrenia and schizoaffective patients and 22 age and sex-matched controls) were enrolled. Patients were divided in resistant (TRS, n=19) and non-resistant to pharmacological treatment (non-TRS, n=22) according to the American Psychiatric Association (APA) criteria for treatment resistance. The Brief Assessment of Cognition in Schizophrenia (BACS) was administered to patients and controls. The following rating scales were administered to schizophrenia patients: the Positive and Negative Syndrome Scale (PANSS), the Drug Attitude Inventory (DAI) and the Subjective Well-being under Neuroleptics (SWN). Statistically significant differences among non-TRS patients, TRS ones, and controls were detected at the BACS. TRS patients performed significantly worse than non-TRS ones on Verbal Memory task, exhibited higher PANSS total and subscales scores and were prescribed higher antipsychotic doses. Poorer performances at the BACS significantly correlated with more severe negative symptoms in TRS but not in non-TRS patients. These results may suggest that TRS patients suffer from a form of the disease with prominent cognitive impairment possibly related to negative symptoms.

A review of the pharmacology, efficacy and tolerability of recently approved and upcoming oral antipsychotics: an evidence-based medicine approach

Evidence-based medicine (EBM) is a broad concept, but the key elements include the incorporation of clinical judgment (which requires clinical experience) together with relevant scientific evidence while remaining mindful of the individual patient's values and preferences. Using the framework and philosophy of EBM, this systematic review summarizes the pharmacology, efficacy, and tolerability of newly approved oral antipsychotics, including iloperidone, asenapine, and lurasidone, and outlines what is known about agents that are in late-stage clinical development, such as cariprazine, brexpiprazole, zicronapine, bitopertin, and EVP-6124. Potential advantages and disadvantages of these agents over existing antipsychotics are outlined, centered on clinically relevant issues such as the potential for weight gain and metabolic abnormalities, potential association with somnolence/sedation, extra-pyramidal side effects, akathisia, and prolongation of the electrocardiogram (ECG) QT interval, as well as practical issues regarding dosing instructions, titration requirements, and drug-drug interactions. Lurasidone appears to be best in class in terms of minimizing untoward alterations in body weight and metabolic variables. However, iloperidone, asenapine, lurasidone, and cariprazine differ among themselves in terms of on-label dosing frequency (once daily for lurasidone and, presumably, cariprazine versus twice daily for iloperidone and asenapine), the need for initial titration to a therapeutic dose for iloperidone and possibly cariprazine, requirement to be taken sublingually for asenapine, requirement for administration with food for lurasidone, lengthening of the ECG QT interval (greater for iloperidone than for asenapine and no effect observed with lurasidone), and adverse effects such as akathisia (seen with cariprazine, lurasidone, and asenapine but not with iloperidone) and sedation (most notable with asenapine).

Cariprazine: chemistry, pharmacodynamics, pharmacokinetics, and metabolism, clinical efficacy, safety, and tolerability

INTRODUCTION

Cariprazine is an atypical antipsychotic in clinical development for the treatment of schizophrenia and bipolar mania/mixed episodes.

AREAS COVERED

The purpose of this review is to describe the chemistry, pharmacodynamic profile, pharmacokinetics, and clinical profile of cariprazine.

EXPERT OPINION

Cariprazine is a dopamine D3-preferring D3/D2 receptor partial agonist. Doses ≥ 1.5 mg/d yielded 69 - 75% D2/D3 receptor occupancy as measured in positron emission tomography scans. Mean half-life for cariprazine was 2 - 5 d over a dose range of 1.5 - 12.5 mg. Cariprazine produces two clinically relevant metabolites: desmethyl-cariprazine and didesmethyl-cariprazine, the latter having a longer half-life than cariprazine. Exposure to didesmethyl-cariprazine exceeded that of the parent drug. Cariprazine is metabolized by CYP3A4 and to a lesser extent by CYP2D6. The efficacy and safety of cariprazine have been so far investigated only in a few short-term (unpublished) clinical trials; however, three studies in schizophrenia and three studies in bipolar mania/mixed episodes evidenced a statistically significant therapeutic effect compared to placebo for cariprazine at doses ranging from 1.5 to 12 mg/d. There does not appear to be clinically relevant adverse effects of cariprazine on metabolic variables. Commonly encountered adverse events associated with cariprazine include insomnia, extrapyramidal symptoms, akathisia, sedation, nausea, dizziness, and constipation.

Asenapine for the treatment of manic and mixed episodes associated with bipolar I disorder: from clinical research to clinical practice

INTRODUCTION

Asenapine is a sublingually administered second-generation antipsychotic with proven efficacy for the treatment of moderate to severe manic episodes associated with bipolar I disorder in adults. Its relatively favorable weight and metabolic profile, as well as the lack of appreciable activity at muscarinic cholinergic receptors and the sublingual administration are of clinical interest.

AREAS COVERED

This paper comprises a review and commentary regarding the use of sublingual asenapine in the treatment of acute manic and mixed episodes of bipolar disorder. Basic principles in dosing, switching, management of side effects and co-administration with other medications are provided.

EXPERT OPINION

Asenapine displays quick and reliable effects on manic symptoms, very low risk of depressive switches, efficacy on depressive symptoms during manic and mixed episodes, usually good tolerability and continued longer-term efficacy on residual and subthreshold symptoms. The fast-dissolving sublingual route of administration may favor those who have difficulties in swallowing medications. Also, the sublingual administration reduces the risk of overdose when more than the prescribed tablets are swallowed. The relatively low metabolic risk and the lack of anticholinergic side effects contribute to making this medication a useful tool for the treatment of patients with bipolar disorder.

Oral antipsychotic update: a brief review of new and investigational agents for the treatment of schizophrenia

Antipsychotics are the mainstay of treatment for patients with schizophrenia. However, these medications only work if they are taken and perhaps work best if they are taken for longer periods of time than seen in typical research trials. Here we explore the idea of "time as drug" by reviewing the data showing the potential benefits of long-term antipsychotic use. We also discuss the utility of depot antipsychotic formulations for improving the chances of attaining long-term therapeutic results.

Paliperidone: a review of clinical trial data and clinical implications

Paliperidone, 9-hydroxy-risperidone, is the major metabolite of the atypical antipsychotic risperidone and is available in an oral extended-release (ER) formulation. Paliperidone ER was approved for treating schizophrenia in 2006, and in 2009 it became the first atypical antipsychotic licensed for treating schizoaffective disorder. The short-term efficacy, safety and tolerability of paliperidone ER for patients with schizophrenia were demonstrated in three pivotal 6-week, randomized, double-blind, placebo-controlled studies. Data from the long-term trial showed that paliperidone ER is also effective in preventing relapse of schizophrenia. Two randomized, placebo-controlled, short-term studies have documented the efficacy and tolerability of paliperidone ER in the treatment of schizoaffective disorder, but no long-term or maintenance study has been conducted in patients with schizoaffective disorder. Two 3-week, randomized, double-blind, placebo-controlled studies showed that paliperidone ER is significantly superior to placebo for treating patients with bipolar disorder, but the results were driven by certain subpopulations. Limited evidence suggests that paliperidone ER can potentially be superior to quetiapine and risperidone. However, few direct head-to-head comparisons between paliperidone ER and other antipsychotics have been conducted to confirm these results. The distinctive pharmacological characteristics of paliperidone ER, including smooth fluctuations in plasma drug concentrations, predominantly renal excretion, low risk of causing hepatic impairment and low drug-drug interaction, might provide important clinical advantages compared with risperidone. However, certain side effects require clinical attention. The rate of extrapyramidal side effects was considerably higher than that of a placebo at doses ≥9 mg/day. The risks for orthostatic hypotension, prolongation of the corrected QT interval and hyperprolactinaemia are also concerns. This review summarizes the currently published data on paliperidone ER for treating patients with schizophrenia, schizoaffective disorder and bipolar disorder, and suggests its appropriate use in clinical practice.

Efficacy and safety of aripiprazole in child and adolescent patients

Aripiprazole (APZ) has a unique pharmacological profile, as a partial agonist at the dopamine D2 and serotonin 5HT1A receptors and an antagonist at the serotonin 5HT2A receptor; this drug has few side effects (such as extrapyramidal syndrome, hyperprolactinemia, weight gain, metabolic disorders, and sedation) which are typical problems with other antipsychotic drugs. Due to its high tolerability, it is possible to safely administer it to children and adolescents. Efficacy and tolerability of APZ in children and adolescents have been well demonstrated in many clinical studies, which supported approvals granted by the US Food and Drug Administration (FDA) for schizophrenia, bipolar diseases, and irritability associated with autistic disorder in children and adolescents. APZ is expected to exert sedative, anti-depressive, and anti-anxiety effects, and stabilize emotion. APZ is an antipsychotic drug which could be useful for a wider spectrum of psychiatric disorders in children and adolescents. There is little risk of deterioration (such as disinhibition and acting out) and rapid stabilization is easy to achieve in children and adolescents without definitive diagnoses or with a combination of more than one spectrum of disorders. The effectiveness of APZ in children and adolescents is reviewed and discussed, given its pharmacological profile and the outcomes of various clinical studies. However, randomized or blind studies are still limited, and the majority of reports referenced here are open-label studies and case reports. Conclusions drawn from such studies must be evaluated with caution, and a further accumulation of controlled studies is thus needed.

Lurasidone for schizophrenia: what's different?

Lurasidone is one of several antipsychotics approved in the recent past by the US FDA for the treatment of schizophrenia. Several Phase II and III studies have established that lurasidone is more efficacious than placebo. There are no available adequately powered head-to-head comparisons of efficacy of lurasidone with other antipsychotics. However, in contrast to some other antipsychotics, lurasidone is associated with minimal weight gain and no clinically meaningful alterations in glucose, lipids, or the ECG QT interval. As per the product label, the recommended starting dose is 40 mg/day and the maximum recommended dose is 80 mg/day. Higher doses do not appear to be more efficacious, and may be associated with increases in adverse effects, such as somnolence and akathisia; however, this tolerability issue was not observed in one recently conducted 6-week study when lurasidone was administered at a dose of 160 mg/day. It is recommended that lurasidone be administered once daily with at least 350 calories of food. Additional studies are desirable to directly compare and contrast lurasidone with other antipsychotic agents.

Paliperidone palmitate injection for the acute and maintenance treatment of schizophrenia in adults

PURPOSE

To review the use of paliperidone palmitate in treatment of patients with schizophrenia.

METHODS

Published clinical trial data for the development and utilization of paliperidone palmitate for the treatment of schizophrenia were assessed in this review. Four short-term, randomized, double-blind, placebo-controlled trials investigated the efficacy of paliperidone palmitate in acute exacerbation of schizophrenia. Paliperidone palmitate was also studied as a maintenance treatment to prevent or delay relapse in stable schizophrenia. In addition, paliperidone palmitate was compared to risperidone long-acting injection for noninferiority in three studies.

RESULTS

Paliperidone palmitate has been shown to be effective in reducing symptoms as measured by the Positive and Negative Syndrome Scale total scores in the four acute treatment studies. In the maintenance treatment studies, paliperidone palmitate was found to be more effective than placebo in preventing or delaying the time to first relapse in stable schizophrenia patients. In addition, paliperidone palmitate was shown to be noninferior to risperidone long-acting injection in two studies. It was shown to be reasonably well tolerated in all clinical trials. Acute treatment phase should be initiated with a dose of 234 mg on day one and 156 mg on day eight, followed by a recommended monthly maintenance dose of 39-234 mg based on efficacy and tolerability results from the clinical studies.

CONCLUSION

Providing an optimal long-term treatment can be challenging. Paliperidone palmitate can be used as an acute treatment even in outpatient setting, and it has shown to be well tolerated by patients. Also, it does not require overlapping oral antipsychotic supplementation while being initiated, and is dosed once per month.

On-label on the table: what the package insert informs us about the tolerability profile of oral atypical antipsychotics, and what it does not

INTRODUCTION

The product label is commonly used as an authoritative source for drug information, especially for new medications that have a limited published evidence base. Key elements of the product label are descriptions of safety and tolerability.

AREAS COVERED

The package inserts of oral atypical antipsychotics approved by the US Food and Drug Administration are reviewed with regard to product safety and tolerability.

EXPERT OPINION

Product labels of oral second-generation antipsychotics provide an opportunity to indirectly compare the safety and tolerability profiles of each agent. Some warnings and precautions are found across the entire class; other warnings and precautions may be worded somewhat differently from agent to agent and some may be unique to a particular medication. Guidance is provided in the product label regarding use in specific populations, drug-drug interactions and other issues relating to dosing. Common adverse reactions are tabulated but the reader is left to calculate the risk differences from placebo and number needed to harm. The latter can be helpful in appraising potential differences in discontinuation rates because of adverse reactions, the proportion gaining at least 7% in body weight from baseline in short-term studies, the proportion experiencing somnolence and the proportion experiencing akathisia. The product label, although limited in terms of being product-specific, is often the most authoritative and accessible source of information about new agents in the marketplace. However, clinicians will need to mind the gap between the efficacy and preliminary safety and tolerability data provided by registration trials and the real-world effectiveness of medications when used in the clinic.

Treatment strategies for dosing the second generation antipsychotics

BACKGROUND

The second generation antipsychotics now have clinical approvals for the treatment of schizophrenia, bipolar depression, bipolar mania, autism, major depressive disorder and are used furthermore off-label to treat other mental disorders. Each agent is unique in its pharmacodynamic profile and allows for unique dosing strategies to be employed when treating these different disorders.

AIMS

To review relevant data regarding the second generation antipsychotics and their empirical dosing strategies. To further review and comment theoretically in these areas where substantial, definitive data are lacking.

MATERIALS AND METHODS

A MEDLINE and recent textbook review was conducted regarding each second generation antipsychotic and cross-referenced with searches for major mental disorders. The findings are compiled in the review below.

DISCUSSION

The second generation antipsychotics are clearly delineated in the treatment of psychosis and mania and share similar mechanisms of action to achieve these results: dopamine-2 receptor antagonism for efficacy and serotonin-2a receptor antagonism for EPS tolerability. From here, each agent has a unique pharmacodynamic and pharmacokinetic profile where some agents carry more, or less antidepressant, anxiolyic, or hypnotic profiles. Choosing an agent, and dosing it in low, middle, or high ranges may result in differential effectiveness and tolerability.

CONCLUSION

The second generation antipsychotics have many clinical applications in psychiatric practice. This article serves to review this and also suggests ways clinicians may optimize treatment based upon patient diagnosis and utilizing appropriate dosing of each individual second generation antipsychotic.

Role of sublingual asenapine in treatment of schizophrenia

Asenapine tablets are a new option for the treatment of schizophrenia. Sublingual administration is essential because bioavailability if ingested is less than 2%. Efficacy is supported by acute and long-term randomized controlled studies conducted by the manufacturer, with asenapine 5 mg twice daily evidencing superiority over placebo in six-week studies of acute schizophrenia, and flexibly-dosed asenapine (modal dose 10 mg twice daily) superior to placebo in a 26-week maintenance of response study. Tolerability advantages over some second-generation antipsychotics, such as olanzapine, include a relatively favorable weight and metabolic profile, as demonstrated in a 52-week randomized, head-to-head, double-blind clinical trial. Although dose-related extrapyramidal symptoms and akathisia can be present, the frequency of these effects is lower than that for haloperidol and risperidone. Somnolence may also occur, and appears to be somewhat dose-dependent when examining rates of this among patients receiving asenapine for schizophrenia and bipolar disorder. Prolactin elevation can occur, but at a rate lower than that observed for haloperidol or risperidone. Unique to asenapine is the possibility of oral hypoesthesia, occurring in about 5% of participants in the clinical trials. Obstacles to the use of asenapine are the recommendations for twice-daily dosing and the need to avoid food or liquids for 10 minutes after administration, although the bioavailability is only minimally reduced if food or liquids are avoided for only two minutes.

Drug safety evaluation of ziprasidone

INTRODUCTION

Ziprasidone is a second-generation antipsychotic approved for the treatment of schizophrenia and bipolar disorder. The purpose of this review is to assess the overall safety profile of ziprasidone, including its risk for prolonging the electrocardiogram (ECG) QT interval.

AREAS COVERED

This paper is a review of product labeling and English language reports located through PubMed and information available on regulatory agency websites, with a focus on the safety and tolerability of ziprasidone.

EXPERT OPINION

Although ziprasidone can prolong the ECG QT interval, this has not resulted in increases in sudden death or cardiac sudden death as noted in a large, simple trial and supported by almost a decade of real-world use in the US. Ziprasidone's principal advantage over some other second-generation antipsychotics has been its overall favorable weight and metabolic profile. Similar to most second-generation antipsychotics, ziprasidone has a lower propensity for extrapyramidal side effects and hyperprolactinemia compared to first-generation antipsychotics.

Lurasidone for schizophrenia: a review of the efficacy and safety profile for this newly approved second-generation antipsychotic

OBJECTIVE

To describe the efficacy and safety of lurasidone for the treatment of schizophrenia.

DATA SOURCES

The pivotal registration trials were accessed by querying the literature databases PubMed, EMBASE, ISI Web of Knowledge, as well as http://www.fda.gov and http://www.clinicaltrials.gov for the search term 'lurasidone'. Product labelling provided additional information.

STUDY SELECTION

All available clinical reports of studies were identified.

DATA EXTRACTION

Descriptions of the principal results and calculation of number needed to treat (NNT) and number needed to harm (NNH) for relevant dichotomous outcomes were extracted from the available study reports, abstracts and posters. Additional safety outcomes subject to NNH analysis were obtained from product labelling.

DATA SYNTHESIS

Lurasidone is a second-generation antipsychotic approved for the treatment of schizophrenia at a recommended starting dose of 40 mg/day administered once daily with food (≥350 calories). The maximum recommended dose is 80 mg/day. Regulatory approval was based primarily on a clinical trial programme that included four 6-week randomised clinical trials demonstrating efficacy vs. placebo in acute patients with schizophrenia. One additional Phase II clinical trial was considered a failed study because neither lurasidone nor the active control, haloperidol, separated from placebo on the primary outcome measure. One additional Phase III study was completed after the new drug application was submitted to the US Food and Drug Administration. Efficacy outcomes appear consistently in favour of lurasidone 80 mg/day vs. placebo on multiple measures of psychopathology, however, at least two studies also demonstrated efficacy for the doses of 40 and 120 mg/day. NNT vs. placebo was 3-6 for response as defined by ≥20% reduction in psychopathological rating scale total scores from baseline, depending on the study and the dose. Response as defined by a ≥30% improvement yielded NNTs ranging from 7 to 13. The most common adverse events in the clinical trials were somnolence (broadly defined), akathisia, nausea, parkinsonism and agitation. As estimated from product labelling, NNH vs. placebo was dose dependent for somnolence, with a NNH of 6 for lurasidone 120 mg/day, compared with NNHs of 8, 11 and 20, for 80, 40 and 20 mg/day, respectively. For akathisia NNH was 6 for lurasidone 120 mg/day, compared to NNHs of 9, 13 and 34 for 80, 40 and 20 mg/day, respectively. Lurasidone is associated with minimal weight gain and no clinically meaningful alterations in glucose, lipids, prolactin or the ECG QT interval.

CONCLUSIONS

Lurasidone 40 and 80 mg/day appear efficacious and tolerable in the treatment of schizophrenia. Doses above 80 mg/day do not appear to confer added benefit and may be associated with a dose-related increase in certain adverse reactions. Principal advantages over some other second-generation antipsychotics are lurasidone's highly favourable metabolic profile and once-daily dosing regimen. Additional data regarding long-term efficacy and effectiveness will help characterise this new agent when used in maintenance treatment.

Iloperidone: chemistry, pharmacodynamics, pharmacokinetics and metabolism, clinical efficacy, safety and tolerability, regulatory affairs, and an opinion

IMPORTANCE OF THE FIELD

Iloperidone is a newly commercialized second-generation (atypical) antipsychotic approved for the acute treatment of schizophrenia in adults.

AREAS COVERED IN THIS REVIEW

the purpose of this review is to describe the pharmacokinetic profile of iloperidone and its clinical implications in the treatment of schizophrenia. Background information is also provided regarding chemistry, pharmacodynamics, clinical efficacy and safety data, and regulatory affairs.

WHAT THE READER WILL GAIN

the reader will have an understanding of the pharmacokinetics and overall metabolism of iloperidone within the context of efficacy and safety.

TAKE HOME MESSAGE

time to peak plasma concentration occurs in 2 - 4 h but elimination half-life is 18 h for extensive CYP2D6 metabolizers and 33 h for poor CYP2D6 metabolizers, suggesting that once or twice daily dosing would be feasible. Dizziness and/or postural hypotension are the limiting factors for how fast iloperidone can be titrated, and is explained by iloperidone and its metabolites' norepinephrine alpha 1 antagonism. Efficacy of iloperidone appears similar to that for ziprasidone and haloperidol, but iloperidone may be inferior in efficacy to risperidone. Iloperidone can prolong the ECG QT interval. The tolerability profile of iloperidone is noteworthy in terms of modest weight gain, no medically important changes in lipid and glucose, little in the way of prolactin elevation, and an absence of extrapyramidal adverse effects, including akathisia.

Quetiapine and norquetiapine in plasma and cerebrospinal fluid of schizophrenic patients treated with quetiapine: correlations to clinical outcome and HVA, 5-HIAA, and MHPG in CSF

This study investigated concentrations of quetiapine and norquetiapine in plasma and cerebrospinal fluid (CSF) in 22 schizophrenic patients after 4-week treatment with quetiapine (600 mg/d), which was preceded by a 3-week washout period. Blood and CSF samples were obtained on days 1 and 28, and CSF levels of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) concentrations were measured at baseline and after 4 weeks of quetiapine, allowing calculations of differences in HVA (ΔHVA), 5-HIAA (Δ5-HIAA), and MHPG (ΔMHPG) concentrations. Patients were assessed clinically, using the Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression Scale at baseline and then at weekly intervals. Plasma levels of quetiapine and norquetiapine were 1110 ± 608 and 444 ± 226 ng/mL, and the corresponding CSF levels were 29 ± 18 and 5 ± 2 ng/mL, respectively. After the treatment, the levels of HVA, 5-HIAA, and MHPG were increased by 33%, 35%, and 33%, respectively (P < 0.001). A negative correlation was found between the decrease in PANSS positive subscale scores and CSF ΔHVA (r(rho) = -0.690, P < 0.01), and the decrease in PANSS negative subscale scores both with CSF Δ5-HIAA (r(rho) = -0.619, P = 0.02) and ΔMHPG (r(rho) = -0.484, P = 0.038). Because, unfortunately, schizophrenic patients experience relapses even with the best available treatments, monitoring of CSF drug and metabolite levels might prove to be useful in tailoring individually adjusted treatments.

Relationship between dopamine D2 receptor occupancy, clinical response, and drug and monoamine metabolites levels in plasma and cerebrospinal fluid. A pilot study in patients suffering from first-episode schizophrenia treated with quetiapine

Combining measurements of the monoamine metabolites in the cerebrospinal fluid (CSF) and neuroimaging can increase efficiency of drug discovery for treatment of brain disorders. To address this question, we examined five drug-naïve patients suffering from schizophrenic disorder. Patients were assessed clinically, using the Positive and Negative Syndrome Scale (PANSS): at baseline and then at weekly intervals. Plasma and CSF levels of quetiapine and norquetiapine as well CSF 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindole-acetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were obtained at baseline and again after at least a 4 week medication trail with 600 mg/day quetiapine. CSF monoamine metabolites levels were compared with dopamine D(2) receptor occupancy (DA-D(2)) using [(18)F]fallypride and positron emission tomography (PET). Quetiapine produced preferential occupancy of parietal cortex vs. putamenal DA-D(2), 41.4% (p<0.05, corrected for multiple comparisons). DA-D(2) receptor occupancies in the occipital and parietal cortex were correlated with CSF quetiapine and norquetiapine levels (p<0.01 and p<0.05, respectively). CSF monoamine metabolites were significantly increased after treatment and correlated with regional receptor occupancies in the putamen [DOPAC: (p<0.01) and HVA: (p<0.05)], caudate nucleus [HVA: (p<0.01)], thalamus [MHPG: (p<0.05)] and in the temporal cortex [HVA: (p<0.05) and 5-HIAA: (p<0.05)]. This suggests that CSF monoamine metabolites levels reflect the effects of quetiapine treatment on neurotransmitters in vivo and indicates that monitoring plasma and CSF quetiapine and norquetiapine levels may be of clinical relevance.