Cariprazine in the treatment of schizophrenia: a proof-of-concept trial

Comparing the latent state-trait structure of the PANSS in cariprazine-medicated and placebo-controlled patients with acute schizophrenia

After over a hundred years of research, the question whether the symptoms of schizophrenia are rather trait-like (being a relatively stable quality of individuals) or state-like (being substance to change) is still unanswered. To assess the trait and the state component in patients with acute schizophrenia, one group receiving antipsychotic treatment, the other not. Data from four phase II/III, 6-week, randomized, double-blind, placebo-controlled trials of similar design that included patients with acute exacerbation of schizophrenia were pooled. In every trial, one treatment group received a third-generation antipsychotic, cariprazine, and the other group placebo. To assess symptoms of schizophrenia, the Positive and Negative Symptom Scale (PANSS) was applied. Further analyses were conducted using the five subscales as proposed by Wallwork and colleagues. A latent state-trait (LST) model was developed to estimate the trait and state components of the total variance of the observed scores. All symptom dimensions behaved more in a trait-like manner. The proportions of all sources of variability changed over the course of the observational period, with a bent around weeks 3 and 4. Visually inspected, no major differences were found between the two treatment groups regarding the LST structure of symptom dimensions. This high proportion of inter-individual stability may represent an inherent part of symptomatology that behaves independently from treatment status.

A 12-month longitudinal naturalistic follow-up of cariprazine in schizophrenia

Background

Cariprazine, a third-generation antipsychotic (TGAs), has demonstrated efficacy in the treatment of schizophrenia with good tolerability profile. Actual real-world literature data are lacking, particularly when exploring its efficacy in the long term. The present study examined the effects of cariprazine treatment on specific psychopathological domains with a particular focus on outcomes and side effects in real-life experience, after a long-term treatment.

Methods

The present 12-month longitudinal naturalistic study included a sample of subjects with a DSM-5-TR diagnosis of schizophrenia, recruited in the outpatients' psychiatric services of university and community hospitals in Italy, naturally treated with cariprazine. The assessments included: a sociodemographic data sheet, the Structured Clinical Interview for the DSM-5 (SCID-5), the Positive and Negative Symptom Scale (PANSS) and the St. Hans Rating Scale (SHRS). The PANSS was also administered after 6 (T1) and 12 (T2) months of treatment with cariprazine while the SHRS at T1.

Results

The total sample consisted of 31 patients, 15 males and 16 females. A significant decrease of the PANSS' subscales, Marder factors and total mean scores emerged at both T1 and T2 with respect to T0. Extrapyramidal symptoms occurred in a minority of patients and in mild or mild/moderate forms: no patient showed moderate forms of psychic/motor akathisia or dystonia, three subjects showed moderate parkinsonism.

Conclusions

This study confirms a good efficacy profile of cariprazine in both positive and negative symptoms in patients with Schizophrenia, combined with a good tolerability profile in extrapyramidal symptoms.

Switching antipsychotics to partial dopamine D2-agonists in individuals affected by schizophrenia: a narrative review

OBJECTIVE

The aim of this review is to analyse the literature regarding studies centred on the clinical outcome of individuals affected by schizophrenia and treated with various antipsychotics, and then switched to orally administered partial D2-dopamine agonists (PD2A): Aripiprazole (ARI), brexpiprazole (BREX) or cariprazine (CARI).

METHOD

A PubMed literature search was performed on 16 February 2021, and updated on Jan 26, 2022 for literature on antipsychotic switching in individuals affected by schizophrenia. Literature was included from 2002 onward. Six strategies were defined: Abrupt, gradual and cross-taper switch, and 3 hybrid strategies. The primary outcome was all-cause discontinuation rate per switch strategy per goal medication.

RESULTS

In 10 reports on switching to ARI, 21 studies with different strategies were described, but there were only 4 reports and 5 strategies on switching to BREX. Only one study about CARI was included, but it was not designed as a switch study. The studies are difficult to compare due to differences in methodology, previous antipsychotic medication, doses of the introduced P2DA and study duration.

CONCLUSION

This analysis did not reveal evidence for a preferable switching strategy. A protocol should be developed which defines optimal duration, instruments to be used, and the timing of the exams.KEY MESSAGESMost switch studies on partial D2-agonists focus on ARI, with only a few on BREX, while little is known about the clinical outcome of switching individuals to CARIThere is a wide variation of possible switch methods: Abrupt switch - gradual switch - cross-tapering switch - hybrid strategies including plateau switchThe protocols used differ considerably between the studies. A strict comparison between the studies is difficult, for which reason the present evidence does not support an unambiguous preference for a particular switch strategy.From a methodological point of view, a standardised clinical protocol should be developed to allow comparisons between studies regarding the clinical outcome of individuals switched from one antipsychotic drug to another.

Cariprazine in an Adolescent with Tourette Syndrome with Comorbid Attention Deficit Hyperactive Disorder and Depression: A Case Report

Tourette syndrome is a complex neuropsychiatric condition that manifests in childhood and is often associated with other psychiatric comorbidities. This case report describes a young male with Tourette syndrome with major depressive disorder and attention deficit hyperactivity disorder (ADHD) who experienced troublesome side effects due to his existing medications (escitalopram, risperidone, and methylphenidate). In order to control his tics, ameliorate depressive symptoms, and eliminate side effects of stiffness and sedation, risperidone was switched to cariprazine, a third-generation antipsychotic medication with D3-D2 partial agonism. In addition, the antidepressant dose was also increased. With the new combination, the patient reported good control of his tics, together with significant improvement in depressive symptoms and no side effects. Based on this case and the reviewed literature, cariprazine might be a viable option for patients with Tourette syndrome with other comorbid illnesses who are prone to side effects of medication.

Adverse effects of antipsychotics on sleep in patients with schizophrenia. Systematic review and meta-analysis

Introduction

Our objective was to conduct a systematic review and meta-analysis of adverse effects on sleep in patients with schizophrenia receiving antipsychotic treatment.

Methods

A systematic search was performed in PubMed, Cochrane Central, Embase, Toxline, Ebsco, Virtual Health Library, Web of Science, SpringerLink, and in Database of abstracts of Reviews of Effects of Randomized Clinical Trials to identify eligible studies published from January 1990 to October 2021. The methodological quality of the studies was evaluated using the CONSORT list, and the Cochrane bias tool. Network meta-analysis was performed using the Bayesian random-effects model, with multivariate meta-regression to assess the association of interest.

Results

87 randomized clinical trials were identified that met the inclusion criteria, and 70 articles were included in the network meta-analysis. Regarding the methodological quality of the studies, 47 had a low or moderate bias risk. The most common adverse effects on sleep reported in the studies were insomnia, somnolence, and sedation. The results of the network meta-analysis showed that ziprasidone was associated with an increased risk of insomnia (OR, 1.56; 95% credible interval CrI, 1.18-2.06). Several of the included antipsychotics were associated with a significantly increased risk of somnolence; haloperidol (OR, 1.90; 95% CrI, 1.12-3.22), lurasidone (OR, 2.25; 95% CrI, 1.28-3.97) and ziprasidone (OR, 1.79; 95% CrI, 1.06-3.02) had the narrowest confidence intervals. In addition, perphenazine (OR, 5.33; 95% CrI, 1.92-14.83), haloperidol (OR, 2.61; 95% CrI, 1.14-5.99), and risperidone (OR, 2.41; 95% CrI, 1.21-4.80) were associated with an increased risk of sedation compared with placebo, and other antipsychotics did not differ. According to the SUCRAs for insomnia, chlorpromazine was ranked as the lowest risk of insomnia (57%), followed by clozapine (20%), while flupentixol (26 %) and perospirone (22.5%) were associated with a lower risk of somnolence. On the other hand, amisulpride (89.9%) was the safest option to reduce the risk of sedation.

Discussion

Insomnia, sedation, and somnolence were the most frequent adverse effects on sleep among the different antipsychotics administered. The evidence shows that chlorpromazine, clozapine, flupentixol, perospirone, and amisulpride had favorable safety profiles. In contrast, ziprasidone, perphenazine, haloperidol, and risperidone were the least safe for sleep.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42017078052, identifier: PROSPERO 2017 CRD42017078052.

Cariprazine for Treating Schizophrenia, Mania, Bipolar Depression, and Unipolar Depression: A Review of Its Efficacy

This drug review presents a comprehensive review of Cariprazine, a medication that received FDA approval in 2015 for treating schizophrenia and bipolar disorder. The paper begins by exploring Cariprazine's mechanism of action, which involves modulating dopamine and serotonin receptors. Additionally, the review assesses Cariprazine's metabolic profile and notes its low potential for weight gain and metabolic side effects. The study examines Cariprazine's efficacy and safety in treating various psychiatric disorders, such as schizophrenia, bipolar maintenance, mania, and bipolar depression. A meticulous analysis of clinical trials is included, demonstrating Cariprazine's potential advantages over existing medications used for these disorders. Additionally, the review covers Cariprazine's recent approval as an adjuvant treatment for unipolar depression. Furthermore, the paper examines the limitations of Cariprazine, such as the absence of head-to-head trials comparing it to other commonly used medications for these disorders. The paper concludes by emphasizing the need for more research to establish Cariprazine's position in treating schizophrenia and bipolar disorder and determine its comparative effectiveness with other available treatments.

Systematic literature review and network meta-analysis of lurasidone, brexpiprazole and cariprazine for schizophrenia

A systematic review was undertaken to identify randomized controlled trials (RCTs) comparing the efficacy and safety of lurasidone, brexpiprazole and cariprazine (selected because of a shared safety profile) with each other or placebo in adult patients with schizophrenia. Key outcomes included: Positive and Negative Syndrome Scales (PANSS), Clinical Global Impression-Severity (CGI-S) scores and cardiovascular and metabolic parameters. A feasibility assessment evaluated the trials' suitability for inclusion in a Bayesian network meta-analysis (NMA). Random effects models were used. In total, 1138 records were identified and 19 RCTs contributed to the NMA. Lurasidone doses of 160 mg performed best in terms of change in PANSS and CGI-S scores at 6 weeks, with stronger evidence when compared with brexpiprazole than cariprazine. The safety outcomes were variable; for all treatments, the 95% credible intervals usually contained 'no difference'. Active treatments were associated with lower odds of discontinuation due to any cause, and higher odds of experiencing any adverse event. Lurasidone was comparable to brexpiprazole and cariprazine for efficacy and safety outcomes assessed at 6 weeks, with the 160 mg dose being superior for the change in PANSS and CGI-S outcomes. The lurasidone results were relatively consistent across doses compared with brexpiprazole and cariprazine.

Successful high dose antipsychotic treatment with cariprazine in patients on the schizophrenia spectrum: Real-world evidence from a Spanish hospital setting

Real-world evidence fills in an important gap by providing data on the effectiveness and tolerability of new medications in everyday patients. In this data collection form a Spanish hospital, the effectiveness and tolerability of cariprazine were evaluated in 14 patients who were admitted to the hospital due to an acute episode of schizophrenia or schizoaffective disorder. The collected data included demographic characteristics, history of disorder and previous treatment, and details of cariprazine therapy such as dosing, side effects and measurements of effectiveness via scales. Difference between admission and discharge on the Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression-Severity (CGI-S) scale scores were evaluated using the Wilcoxon Signed-Rank test. Significant improvement was detected in nearly all patients (one patient dropped out) as measured by the BPRS Total, Negative symptom, Positive symptom, and Hostility scores. At admission, patients were markedly-moderately ill and at discharge the severity was reduced to borderline ill and normal according to the CGI-S. The CGI-Improvement scale also indicated very much and much improvement at discharge. Importantly, patients left the hospital with high doses of cariprazine, i.e., 7.5 mg/day or even 9.0 mg/day, but this did not cause safety problems; cariprazine well-tolerated as only a few patients experienced side effects such as akathisia. The results provide novel evidence regarding the tolerability and effectiveness of cariprazine in high doses patients on the schizophrenia spectrum.

Mini Review on Cariprazine: A Promising Antipsychotic Agent

Cariprazine is a piperazine derivative approved by the USFDA in 2015 as a novel atypical antipsychotic drug (APD) to treat adults with schizophrenia and bipolar manic or mixed episodes in adults. However, due to the partial agonist action on dopamine D₂, D₃ receptors, and serotonin 5-HT_1A receptors as well as the antagonist effect on 5-HT_2A, 5-HT_2B, and H₁ receptors, cariprazine differs pharmacologically from other APDs, both typical and atypical. Moreover, cariprazine also has a unique pharmacokinetic profile due to the formation of two clinically significant metabolites: desmethyl-cariprazine (DCAR) and desmethyl-cariprazine (DDCAR). They are eliminated by CYP3A4 and also, to a lesser extent, by CYP2D6. Here, we also review the effectiveness, safety, as well as current clinical update of cariprazine in bipolar I disorder associated with/without mania and schizophrenia through randomized and post-hoc analysis. The potential benefits of cariprazine as a promising therapeutic alternative in addressing major clinical requirements for better therapy of such severe neuropsychiatric conditions were demonstrated in this summarized review study.

Risk of Drug-induced Movement Disorders with Newer Antipsychotic Agents

Background:

The last decade has seen development of numerous novel antipsychotic drugs with unique mechanisms including long-acting formulations for clinical use. A comparative assessment of these new drugs with each other and previous antipsychotics have not been performed with regards to risk for drug-induced movement disorders (DIMD).

Methods:

Medline was searched from January 2010 to February 2022 for primary research articles and review articles in English using the search terms “extrapyramidal” and “tardive” with individual drug names of novel antipsychotics.

Results:

We identified articles describing the risk of DIMD with 6 novel antipsychotics, 4 novel formulations, and 3 experimental antipsychotics. Both short- and long-term data generally showed comparable to lower risk of DIMD with novel antipsychotics and recent long-acting formulations compared to previously marketed antipsychotics.

Discussion:

Several novel antipsychotics, particularly lumateperone and pimavanserin, show promise in being able to treat psychosis while reducing the risk of DIMD. Long-acting paliperidone may reduce risk of DIMD while other long-acting injectable formulations of SGA have similar risk of DIMD compared to oral formulations. New drug targets for treating psychosis without dopamine blockade also show promise.

Cariprazine for treating psychosis: an updated meta-analysis

Purpose: Early treatment of psychotic illness improves outcomes, reduces relapse rates and should not be delayed. Cariprazine is a promising antipsychotic drug and may be a valuable resource when clinicians are in doubt if psychotic symptoms are due to schizophrenia or bipolar disorder.Materials and Methods: We conducted a systematic review and meta-analysis that included seven studies (n = 2896) analyzing the effect of cariprazine in psychotic symptoms assessed by the positive and negative symptoms scale (PANSS).Results: We found cariprazine to be significantly superior to placebo (Hedges' g = 0.40; 95% CI 0.32-0.49) for acute psychosis independently of primary psychiatric diagnosis and also to be superior to placebo for both schizophrenia (Hedges' g = 0.39; 95% CI 0.29-0.50) and bipolar patients (Hedges' g = 0.43; 95% CI 0.27-0.58).Conclusions: We propose that cariprazine may be useful in treating psychosis independently of nosological differentiation at the beginning of the treatment Key pointsEarly treatment of psychotic illness with antipsychotic medications improves outcomes and reduces relapse rates.Cariprazine was found to be significantly superior to placebo for acute psychosis independently of primary psychiatric diagnosis.Cariprazine may be useful in treating psychosis independently of nosological differentiation between schizophrenia and bipolar disorder at the beginning of the treatment.

Antipsychotic-Induced Weight Gain: Dose-Response Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Weight gain is among the most important side-effects of antipsychotics. It is, however, unclear whether it is associated with antipsychotic doses. We aimed to fill this gap with a dose-response meta-analysis.

METHODS

We searched multiple electronic databases (last update search June 2021) for all fixed-dose studies that investigated 16 second-generation antipsychotics and haloperidol in adults with acute exacerbation of schizophrenia or with negative symptoms. We estimated the dose-response curves by conducting random-effects dose-response meta-analyses. We used the restricted cubic spline to model the dose-response relationship. The primary outcome was mean weight gain in kg from baseline to endpoint, the secondary outcome was the number of patients with clinically important weight gain.

FINDINGS

Ninety-seven studies with 333 dose arms (36 326 participants) provided data for meta-analyses. Most studies were short-term with median duration of 6 weeks (range 4 to 26 weeks). In patients with acute exacerbation, amisulpride, aripiprazole, brexpiprazole, cariprazine, haloperidol, lumateperone, and lurasidone produced mild weight gain in comparison to placebo (mean difference at any dose≤1 kg), while more significant weight gain was observed by all other drugs. For most drugs, dose-response curves showed an initial dose-related increase in weight which plateaued at higher doses, while for others there was no plateau and some even had bell-shaped curves, meaning less weight gain to be associated with higher doses.

INTERPRETATION

Second-generation antipsychotics do not only differ in their propensity to produce weight gain, but also in the shapes of their dose-response curves. This information is important for dosing decisions in clinical practice.

Real-Life Clinical Experience With Cariprazine: A Systematic Review of Case Studies

Background

The hierarchy of evidence coming from evidence-based medicine favors meta-analyses and randomized controlled trials over observational studies and clinical cases. Nonetheless, in the field of psychiatry, where conditions are much more complex, additional evidence coming from real-world clinical practice is necessary to complement data from these gold standards. Thus, in this systematic review, the aim is to summarize the evidence coming from clinical case reports regarding cariprazine, a third-generation antipsychotic drug that has been approved for the treatment of schizophrenia and bipolar I disorder with manic, depressive or mixed features in adults.

Methods

A systematic review was performed using Embase and Pubmed databases searching for English-language cases published in peer-reviewed journals between 2000 January and 2021 September with the following search terms: (cariprazin* OR "rgh-188" OR rgh188 OR vraylar OR reagila) AND ("case report*" OR "case report"/de OR "case stud*" OR "case study"/de OR "case seri*").

Results

After the removal of duplicates, 49 articles were retrieved via the search, from which 22 were suitable for this review. These 22 articles encompassed 38 cases from which 71% described patients with schizophrenia, 16% patients with psychotic disorders, 5% patients with mood disorder and 8% described patients with other disorders such as Wernicke-Korsakoff syndrome, borderline personality disorder and obsessive-compulsive disorder with paranoid schizophrenia. The median age of patients was 31, and half of them were female. The majority of patients (76%) started cariprazine with 1.5 mg/day, and the most common maintenance dose was 4.5 mg/day (34%) and 3.0 mg/day (29%).

Conclusion

Cariprazine was found to be safe and effective in a wide range of psychiatric conditions with different symptom profiles from acute psychotic symptoms through addiction to negative and cognitive symptoms. The results are in-line with the established evidence from clinical trials, however, they also show how cariprazine can be successfully utilized for treating certain symptoms irrespective of the indication.

Dosing Cariprazine Within and Beyond Clinical Trials: Recommendations for the Treatment of Schizophrenia

Although the optimal dosing of an antipsychotic medication is known to be essential in the long-term management of schizophrenia, in case of novel drugs such as cariprazine, determining the right dosing strategy is not that simple. Without decades of experience with a particular compound, evidence regarding dosing and titration comes primarily from double-blind, placebo controlled clinical trials that are not necessarily mirroring the real-life experiences of doctors. Via summarizing data from both clinical data (n = 3275) and real-world evidence (observational study n = 116, case studies n = 29), this perspective paper aims to shed a light on the appropriate dosing strategies of cariprazine from treatment initiation through switching strategies to concomitant medications.

Minimal Effects of Cariprazine on Prolactin Levels in Bipolar Disorder and Schizophrenia

BACKGROUND

Many medications used to treat schizophrenia and bipolar I disorder are linked to hyperprolactinemia. The effects of cariprazine, a dopamine D₃/D₂ receptor partial agonist, on prolactin levels in patients with schizophrenia or bipolar I disorder were evaluated.

METHODS

Effects on prolactin were evaluated using pooled data from randomized, double-blind, placebo-controlled studies in patients with schizophrenia (4 studies; 6-week duration; cariprazine 1.5-3 mg/d, 4.5-6 mg/d, and 9-12 mg/d), bipolar mania (3 studies; 3-week duration; cariprazine 3-6 and 9-12 mg/d), and bipolar depression (3 studies; 6- to 8-week duration; cariprazine 1.5 and 3 mg/d). Long-term effects were analyzed using open-label studies in patients with schizophrenia (2 studies; 48-week duration) and patients with bipolar mania (1 study; 16-week duration). Change in prolactin levels (ng/mL) from baseline to study endpoint was evaluated in subsets of sex and prior medication use.

RESULTS

In patients with schizophrenia (male, n = 1377; female, n = 558), median prolactin changes were -1.2 for males and -7.4 for females on placebo, and ranged from -4.2 to -3.6 for males and -12.4 to +0.2 for females in the cariprazine-treatment groups. In patients with bipolar mania (male, n = 570; female, n = 395), median prolactin changes were -0.2 for males and -1.1 for females on placebo and ranged from -2.1 to -3.0 for males and 0 to +1.8 for females in the cariprazine-treatment groups. Median decreases were also seen in the long-term studies of schizophrenia (range, -14.6 to -2.0) and bipolar mania (range, -0.8 to +1.9). In patients with bipolar depression (male, n = 485; female, n = 780), median prolactin changes were +0.3 for males and +0.7 for females on placebo and ranged from +0.4 to +0.5 for males and +3.0 to +3.1 for females in the cariprazine-treatment groups.

CONCLUSION

Treatment with cariprazine for schizophrenia or bipolar I disorder was associated with minimal effects on prolactin levels.

New and emerging treatments for schizophrenia: a narrative review of their pharmacology, efficacy and side effect profile relative to established antipsychotics

Schizophrenia is associated with substantial unmet needs, highlighting the necessity for new treatments. This narrative review compares the pharmacology, clinical trial data and tolerability of novel medications to representative antipsychotics. Cariprazine, brexpiprazole and brilaroxazine are partial dopamine agonists effective in acute relapse. Lumateperone (serotonin and dopamine receptor antagonist) additionally benefits asocial and depressive symptoms. F17464 (D3 antagonist and 5-HT1A partial agonist) has one positive phase II study. Lu AF35700 (dopamine and serotonin receptor antagonist) was tested in treatment-resistance with no positive results. Pimavanserin, roluperidone, ulotaront and xanomeline do not act directly on the D2 receptor at clinical doses. Initial studies indicate pimavanserin and roluperidone improve negative symptoms. Ulotaront and xanomeline showed efficacy for positive and negative symptoms of schizophrenia in phase II trials. BI 409306, BI 425809 and MK-8189 target glutamatergic dysfunction in schizophrenia, though of these only BI 425809 showed efficacy. These medications largely have favourable cardiometabolic side-effect profiles. Overall, the novel pharmacology, clinical trial and tolerability data indicate these compounds are promising new additions to the therapeutic arsenal.

Newer antipsychotics: Brexpiprazole, cariprazine, and lumateperone: A pledge or another unkept promise?

Antipsychotic agents are used for various indications in the treatment of psychiatric disorders. Despite their proven roles in multiple conditions, the treatment-emergent side effects of antipsychotic medications, such as metabolic side effects, are often the limiting factor for their long-term and short-term uses. Moreover, antipsychotic medications are often criticized for being less effective in treating different disabling symptoms such as negative symptoms of schizophrenia. As a result, the search for safer and more efficacious antipsychotic agents is ongoing. Newer antipsychotic agents are gaining attention related to emerging efficacy and tolerability data in treating neuropsychiatric conditions. In this review, we attempt to appraise the scientific data on psychopharmacology, safety profile, and efficacy of the newer additions to the list of second-generation antipsychotics, namely brexpiprazole, cariprazine, and lumateperone. We conducted a selective review utilizing PubMed, clinicaltrials.gov, and Cochrane databases to gather appropriate publications, keeping broad inclusion criteria. There were no restrictions on the age of the study population or the year of publication. We also cross-referenced articles and references to capture all existing studies. Our review of the current literature indicates that all three antipsychotic agents appear to be promising based on their short-term studies, while long-term studies remain limited. There is also a need for a head to head comparison between the newer antipsychotics with the other antipsychotic agents to ascertain if the newer agents are any better than the others.

New Antipsychotic Medications in the Last Decade

PURPOSE OF REVIEW

Over the last ten years, the treatment of psychosis has seen a near explosion of creative development in both novel agents and new delivery modalities. The current review summarizes these developments over the past decade (2011-2020). We performed a systematic review utilizing PubMed and PsychInfo with the aim of identifying all the RCT and related analyses in adults with psychosis (schizophrenia and mania).

RECENT FINDINGS

We identified 11 significant developments: the introduction of new antipsychotics cariprazine, brexpiprazole, lumateperone, and pimavanserin; introduction of new delivery methods: subcutaneous long-acting risperidone, aripiprazole lauroxil, transdermal asenapine, and inhaled loxapine; and the introduction of new approaches such as olanzapine/samidorphan for olanzapine-associated weight gain, examination of the TAAR1 agonist SEP 363,856 as a test of concept, and the combination of Xanomeline/Trospium, an M₁ and M₄ muscarinic receptor agonist in conjunction with a peripheral anticholinergic. Last decade has seen a tremendous development in second-generation antipsychotics which provides unprecedented treatment options for clinicians in treating psychosis.

Developments in Biological Mechanisms and Treatments for Negative Symptoms and Cognitive Dysfunction of Schizophrenia

The causal mechanisms and treatment for the negative symptoms and cognitive dysfunction in schizophrenia are the main issues attracting the attention of psychiatrists over the last decade. The first part of this review summarizes the pathogenesis of schizophrenia, especially the negative symptoms and cognitive dysfunction from the perspectives of genetics and epigenetics. The second part describes the novel medications and several advanced physical therapies (e.g., transcranial magnetic stimulation and transcranial direct current stimulation) for the negative symptoms and cognitive dysfunction that will optimize the therapeutic strategy for patients with schizophrenia in future.

[The newer antipsychotic cariprazine (reagila): perspectives for use in different stages of schizophrenia therapy]

Cariprazine is a newer 3rd generation antipsychotic acting as partial agonist for dopamine receptors with unique higher affinity for D3 than D2 receptors. This review article summarizes key data from preclinical and clinical studies of cariprazine including pharmacodynamics, pharmacokinetics, clinical efficacy and safety/acceptability in acute short-term and long-term maintenance and relapse prevention therapy in patients with schizophrenia. Efficacy and safety of cariprazine in patients schizophrenia with predominantly negative symptoms resistant to previous antipsychotic therapy is discussed as well.

Examining Side Effect Variability of Antipsychotic Treatment in Schizophrenia Spectrum Disorders: A Meta-analysis of Variance

Side effects of antipsychotic drugs play a key role in nonadherence of treatment in schizophrenia spectrum disorders (SSD). While clinical observations suggest that side effect variability between patients may be considerable, statistical evidence is required to confirm this. Here, we hypothesized to find larger side effect variability under treatment compared with control. We included double-blind, placebo-controlled, randomized controlled trials (RCTs) of adults with a diagnosis of SSD treated with 1 out of 14 antipsychotics. Standard deviations of the pre-post treatment differences of weight gain, prolactin levels, and corrected QT (QTc) times were extracted. The outcome measure was the variability ratio of treatment to control for individual antipsychotic drugs and the overall variability ratio of treatment to control across RCTs. Individual variability ratios were weighted by the inverse-variance method and entered into a random-effects model. We included N = 16 578 patients for weight gain, N = 16 633 patients for prolactin levels, and N = 10 384 patients for QTc time. Variability ratios (VR) were significantly increased for weight gain (VR = 1.08; 95% CI: 1.02-1.14; P = .004) and prolactin levels (VR = 1.38; 95% CI: 1.17-1.62; P < .001) but did not reach significance for QTc time (VR = 1.05; 95% CI: 0.98-1.12; P = 0.135). We found marked differences between individual antipsychotics and increased variability in side effects in patients under treatment with antipsychotics suggesting that subgroups of patients or individual patients may benefit from treatment allocation through stratified or personalized medicine.

Disentangling the symptoms of schizophrenia: Network analysis in acute phase patients and in patients with predominant negative symptoms

Background

The Positive and Negative Syndrome Scale (PANSS) is widely used in schizophrenia and has been divided into distinct factors (5-factor models) and subfactors. Network analyses are newer in psychiatry and can help to better understand the relationships and interactions between the symptoms of a psychiatric disorder. The aim of this study was threefold: (a) to evaluate connections between schizophrenia symptoms in two populations of patients (patients in the acutely exacerbated phase of schizophrenia and patients with predominant negative symptoms [PNS]), (b) to test whether network analyses support the Mohr 5 factor model of the PANSS and the Kahn 2 factor model of negative symptoms, and finally (c) to identify the most central symptoms in the two populations.

Methods

Using pooled baseline data from four cariprazine clinical trials in patients with acute exacerbation of schizophrenia (n = 2193) and the cariprazine–risperidone study in patients with PNS (n = 460), separate network analyses were performed. Network structures were estimated for all 30 items of the PANSS.

Results

While negative symptoms in patients with an acute exacerbation of schizophrenia are correlated with other PANSS symptoms, these negative symptoms are not correlated with other PANSS symptoms in patients with PNS. The Mohr factors were partially reflected in the network analyses. The two most central symptoms (largest node strength) were delusions and uncooperativeness in acute phase patients and hostility and delusions in patients with PNS.

Conclusions

This network analysis suggests that symptoms of schizophrenia are differently structured in acute and PNS patients. While in the former, negative symptoms are mainly secondary, in patients with PNS, they are mainly primary. Further, primary negative symptoms are better conceptualized as distinct negative symptom dimensions of the PANSS.

Antipsychotics for negative and positive symptoms of schizophrenia: dose-response meta-analysis of randomized controlled acute phase trials

Determining the optimal antipsychotic target dose in acute phase treatment is of high clinical relevance. The effect of antipsychotics on negative symptoms should be taken into account because patients will often continue on the treatment received in the acute phase. Therefore, we conducted a formal dose-response meta-analysis of negative symptoms and positive symptoms based on a systematic review of fixed-dose randomized controlled trials (RCTs) that examined the effectiveness of antipsychotics for the acute exacerbation of schizophrenia. Forty RCTs included a total of 15,689 patients. The 95% effective doses per day for the 13 antipsychotics included and 3 long acting were mostly different for negative and positive symptoms: amisulpride (481 mg, 690.6 mg); aripiprazole (11.9 mg, 11 mg); asenapine (7.61 mg, 5.66 mg); brexpiprazole (2.1 mg, 4 mg); cariprazine (4 mg, 6.51 mg); haloperidol (6.34 mg, 7.36 mg); lurasidone (58.2 mg, 86.3 mg); olanzapine (15.5 mg, 9.52 mg); olanzapine long-acting injection (15.7 mg, 13.5 mg); paliperidone (7.2 mg, 7 mg); paliperidone long-acting injection (7.5 mg, 5.9 mg); quetiapine instant-release (264.2 mg, 316.5 mg); quetiapine extended-release (774 mg, 707.2 mg); risperidone (7.5 mg, 7.7 mg); risperidone long-acting injection (5.13 mg, 6.7 mg); sertindole (13.5 mg, 16.3 mg); and ziprasidone (71.6 mg, 152.6 mg). The shape of the dose-response curves varied across different drugs with most drugs showing a plateau at higher doses. Most dose-response curves suggested that the near-maximum effective doses could be in the lower-to-medium range of the licensed dose. Additional RCTs are necessary to establish the optimal dose.

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.

Safety and Tolerability of Cariprazine in Patients with Schizophrenia: A Pooled Analysis of Eight Phase II/III Studies

BACKGROUND

Long-term treatment with antipsychotic agents is indicated for patients with schizophrenia, but treatment is associated with adverse events (AEs) that contribute to medication discontinuation and nonadherence. Understanding drug safety profiles is critical to avoid unwanted side effects. Cariprazine is a potent dopamine D3/D2 receptor partial agonist that is approved for the treatment of adults with schizophrenia (EU, US) and acute manic/mixed and depressive episodes associated with bipolar I disorder (US).

METHODS

Post hoc analyses were conducted to characterize the safety profile of cariprazine within the recommended 1.5-6 mg/d dose range for schizophrenia; data from 8 short- or long-term clinical trials were analyzed.

RESULTS

In the pooled cariprazine-treated safety population (n=2048), the rate of study completion was 52.8%, with withdrawal of consent, insufficient response, and AEs the most common reasons for premature discontinuation. The most commonly reported AEs (>10%) in the overall cariprazine-treatment group were akathisia (14.6%), insomnia (14.0%), and headache (12.1%); most AEs were considered mild (71.0%) or moderate (26.5%). Most akathisia was mild/moderate (97.5%) and >93% of patients remained on treatment; akathisia events were managed by rescue medications (56.3%) or dose reduction (18.3%). The metabolic profile of cariprazine was neutral in patients with short- and long-term exposure; mean weight gain was 1 kg for overall cariprazine, with an AE of weight increased reported for 5.1%. Other AEs of special interest that occurred at >3% for overall cariprazine were extrapyramidal disorder (7.0%), sedation (3.7%), and somnolence (3.1%); prolactin elevation, cognition impairment, sexual dysfunction, suicidality, and QT prolongation occurred at ≤1%.

CONCLUSION

Akathisia, the most common cariprazine-related AE, was mild/moderate and resulted in few study discontinuations; symptoms were well managed and most patients remained on treatment. Results of this analysis indicated that cariprazine in the recommended dose range was safe and generally well tolerated in patients with schizophrenia.

TRIAL REGISTRATION

Studies registered with ClinicalTrials.gov (NCT00404573, NCT01104779, NCT00694707, NCT01104766, NCT01104792, NCT00839852, and NCT01412060) and EudraCT (2012-005485-36).

Cariprazine as a therapeutic option for schizophrenia: a drug evaluation

Introduction: Schizophrenia is a very disabling condition that may result in a significant impairment of individual, professional, and social adjustments. Antipsychotics (APs), the first-line treatment for schizophrenia, in many cases modify the course of the disease, by reducing the institutionalization risk, at the price of severe and invalidating side effects. Cariprazine is one of the latest second-generation APs (SGAs) acting as a partial agonist of type 2 and 3 dopamine receptors, which was recently approved for the treatment of adult schizophrenia.Areas covered: The authors provide a critical review and commentary on the currently available data on the effectiveness and tolerability of cariprazine in schizophrenic patients, with a particular focus on its specific target symptoms.Expert opinion: Cariprazine appears significantly effective on both acute and maintenance treatment of schizophrenia, and in improving positive, negative, and cognitive symptoms, slightly more than other SGAs. It shows a good safety and tolerability profile, with akathisia being its most common side effect. Although further independent studies are needed to clarify its precise advantages over other SGAs, cariprazine seems a promising compound not only in schizophrenia, but also in a broad range of psychiatric conditions, including perhaps bipolar and addictive disorders.

Cariprazine: Patients with Treatment-Resistant Schizophrenia

Schizophrenia is a chronic relapsing and remitting disorder associated with significant impairments in social and vocational functioning and a shortened lifespan, and it is a disabling psychiatric brain syndrome whose phenotype is characterized by three core symptom domains: positive symptoms, such as delusions and hallucinations, negative symptoms, which include lack of motivation and social withdrawal, and cognitive impairment. Moreover, patients with schizophrenia have severe problems with personal and social relations which affect their quality of life. Antipsychotic medications in conjunction with psychosocial interventions can help patients achieve recovery. Here are described three clinical cases of schizophrenic patients treated with cariprazine for inadequate response to a previous treatment. The purpose of this clinical series is to give useful information for the use of cariprazine in clinical practice.

Population Pharmacokinetics of Cariprazine and its Major Metabolites

BACKGROUND AND OBJECTIVES

Cariprazine, a dopamine D₃-preferring D₃/D₂ receptor partial agonist, is approved for the treatment of adults with schizophrenia (1.5-6 mg/day) and manic/mixed (3-6 mg/day) episodes associated with bipolar I disorder. This population pharmacokinetic analysis describes the concentration-time profiles of cariprazine and its two major active metabolites, desmethyl-cariprazine (DCAR) and didesmethyl-cariprazine (DDCAR). Additionally, the potential impact of patient characteristics, creatinine clearance, and cytochrome P450 2D6 (CYP2D6) metabolizer status on the pharmacokinetics of cariprazine and its metabolites was evaluated.

METHODS

Data from three phase 1 and ten phase 2/3 studies in adult patients with schizophrenia or bipolar mania were included. Nonlinear mixed-effects pharmacokinetic modeling was performed using the NONMEM software package. Compartmental modeling was performed sequentially with the cariprazine elimination rate used as the DCAR formation rate and likewise the elimination rate of DCAR used with a delay as the DDCAR formation rate.

RESULTS

Cariprazine pharmacokinetics were described by a three-compartment model with zero-order input of the dose to a depot compartment followed by first-order absorption and first-order elimination. DCAR and DDCAR pharmacokinetics were described by two-compartment models with linear elimination. Statistically significant predictors of pharmacokinetic parameters included weight, sex, and race, though differences in exposures were not large enough to require an adjustment in dose. Creatinine clearance was not a statistically significant predictor of drug clearance, and a post hoc analysis found that CYP2D6 metabolizer status was not associated with changes in exposure levels for cariprazine, DCAR, or DDCAR. The median time to 90% of steady state was approximately 1 week for cariprazine and DCAR and 3 weeks for DDCAR.

CONCLUSIONS

Population pharmacokinetic modeling provided a quantitative description of the concentration-time profile of cariprazine and its metabolites.

Cariprazine to Treat Schizophrenia and Bipolar Disorder in Adults

Purpose of Review

Antipsychotics are the standard of care when it comes to the treatment of Schizophrenia, and they are often used in Bipolar as well. Their use can come with adverse effects such as extrapyramidal movements, metabolic complications as well as cardiovascular complications such as a prolonged QT interval. Treatment for these side effects ranges from the treatment of the complications up to the cessation of the medication, which could come at the expense of the user's stability. Both schizophrenia and bipolar disorder have an increased risk of suicide and increased morbidity. The purpose of this review presents the background, evidence, and indications for the use of the new second-generation antipsychotic Cariprazine, which has a primary function as a D3 and D2 partial agonist, with higher selectivity for the D3 receptor type.

Recent Findings

Schizophrenia is currently teated by dopamine antagonists and/or 5HT modulators, each with their own set of side effects. Bipolar disorder is mostly treated with mood stabilizers. Studies looking at the efficacy and safety of cariprazine have shown in two phase II trials and phase III trials the decrease in PANSS scores in schizophrenia. The most common adverse effects were akathisia, insomnia, constipation, and other extrapyramidal side effects. A unique side effect of Cariprazine caused bilateral cataract and cystic degeneration of the retina in the dog following daily oral administration for 13 weeks and/or 1 year and retinal degeneration in rats following daily oral administration for 2 years. Another study showed that cariprazine had significant efficacy in preventing relapse in patients with schizophrenia. The time to the loss of sustained remission was significantly longer (P = .0020) for cariprazine compared to placebo (hazard ratio = 0.51) during the double-blind treatment. 60.5% of patients treated with cariprazine and 34.9% of patients treated with placebo sustained remission through the final visit (odds ratio [OR] = 2.85; P = .0012; number needed to treat [NNT] = 4. Another Phase IIIb study looked at negative symptoms and used the Positive and Negative Syndrome Scale Factor Score for Negative Symptoms (PANSS-FSNS), and it found that the use of cariprazine, from baseline to week 26, led to a greater least-squares mean change in PANSS-FSNS than did risperidone. Another study looked at the quality of life years with the treatment of cariprazine and showed those treated with cariprazine had superior quality of life compared to those treated with risperidone. In terms of bipolar disorder, it showed a decrease in depressive symptoms as measured by decreased MADRs scores with a dose of 3.0mg/day. A phase II study looked at the use of cariprazine in mania or mix states and showed cariprazine significantly decreased YMRS scores compared to placebo, least-square mean difference of -6.1 (p < 0.001). The metabolic parameters demonstrated comparable changes except for fasting glucose in which cariprazine was associated with elevations in glucose levels compared to placebo (p < 0.05). Another phase III study showed significant differences in YMRS total score mean change between cariprazine versus placebo-treated group. Changes in metabolic profiles in all mentioned studies were minimal.

Summary

Cariprazine, in recent studies, has shown some promise in being able to treat both bipolar disorder in manic, depressed, and mixed states as well as schizophrenia. Side effects noted as adverse events in these studies are similar in profile to the medications that were developed in the past. With better relapse prevention, cariprazine could be a reasonable alternative clozapine.

Cariprazine in Youth with Bipolar and Psychotic Disorders: A Retrospective Chart Review

Objective: To examine the potential effectiveness and tolerability of cariprazine in pediatric bipolar and psychotic disorders. Methods: We retrospectively reviewed the electronic health records of patients <21 years of age prescribed cariprazine to treat bipolar and psychotic disorders. Adverse effects, tolerability, therapeutic response (Clinical Global Impression-Improvement [CGI-I]), and severity of illness (Clinical Global Impression-Severity [CGI-S]) were determined through manual chart review. Results: We identified 16 patients aged 6-20 years who were treated with cariprazine (initial dose: 1.5 mg/day, interquartile range [IQR], 1.5-1.5; endpoint dose: 3 mg/day, IQR, 1.5-4.5). No serious adverse events were reported, but the most commonly reported side effect was weight gain (n = 3, 19%). Of the 14 patients for whom baseline and endpoint body mass index (BMI) data were available, neither changes in BMI (p = 0.391; 0.54 kg/m², IQR, -0.33 to 1.38) nor BMI percentile (p = 0.71; 0.36%, IQR, -0.49 to 3.97) significantly differed between baseline and endpoint. However, patients receiving ≥4.5 mg/day had a significantly greater BMI increases during the course of treatment compared with those receiving ≤3 mg/day (p = 0.034; -1.14 kg/m², IQR, -3.65 to 0.53 vs. 1.01 kg/m², IQR, 0.17-4.88). CGI-S scores (p = 0.016; 4.5, IQR, 4-5 vs. 4, IQR, 3-4) significantly differed from baseline to endpoint. The response rate was 44% (n = 7/16), with responders being prescribed higher doses (p = 0.005; 6 mg/day, IQR, 4.875-6 vs. 3 mg/day, IQR, 3-4.125). Conclusions: Cariprazine may be well tolerated and effective for pediatric bipolar and psychotic disorders; however, compared with higher doses, total daily doses ≤3 mg/day appear to be more tolerable. Prospective controlled studies to further evaluate cariprazine in youth are needed.

Dose-Response Meta-Analysis of Antipsychotic Drugs for Acute Schizophrenia

OBJECTIVE

The dose-response relationships of antipsychotic drugs for schizophrenia are not well defined, but such information would be important for decision making by clinicians. The authors sought to fill this gap by conducting dose-response meta-analyses.

METHODS

A search of multiple electronic databases (through November 2018) was conducted for all placebo-controlled dose-finding studies for 20 second-generation antipsychotic drugs and haloperidol (oral and long-acting injectable, LAI) in people with acute schizophrenia symptoms. Dose-response curves were constructed with random-effects dose-response meta-analyses and a spline model. The outcome measure was total score reduction from baseline on the Positive and Negative Syndrome Scale or the Brief Psychiatric Rating Scale. The authors identified 95% effective doses, explored whether higher or lower doses than the currently licensed ones might be more appropriate, and derived dose equivalencies from the 95% effective doses.

RESULTS

Sixty-eight studies met the inclusion criteria. The 95% effective doses and the doses equivalent to 1 mg of oral risperidone, respectively, were as follows: amisulpride for patients with positive symptoms, 537 mg/day and 85.8 mg; aripiprazole, 11.5 mg/day and 1.8 mg; aripiprazole LAI (lauroxil), 463 mg every 4 weeks and 264 mg; asenapine, 15.0 mg/day and 2.4 mg; brexpiprazole, 3.36 mg/day and 0.54 mg; haloperidol, 6.3 mg/day and 1.01 mg; iloperidone, 20.13 mg/day and 3.2 mg; lurasidone, 147 mg/day and 23.5 mg; olanzapine, 15.2 mg/day and 2.4 mg; olanzapine LAI, 277 mg every 2 weeks and 3.2 mg; paliperidone, 13.4 mg/day and 2.1 mg; paliperidone LAI, 120 mg every 4 weeks and 1.53 mg; quetiapine, 482 mg/day and 77 mg; risperidone, 6.3 mg/day and 1 mg; risperidone LAI, 36.6 mg every 2 weeks and 0.42 mg; sertindole, 22.5 mg/day and 3.6 mg; and ziprasidone, 186 mg/day and 30 mg. For amisulpride and olanzapine, specific data for patients with predominant negative symptoms were available. The authors have made available on their web site a spreadsheet with this method and other updated methods that can be used to estimate dose equivalencies in practice.

CONCLUSIONS

In chronic schizophrenia patients with acute exacerbations, doses higher than the identified 95% effective doses may on average not provide more efficacy. For some drugs, higher than currently licensed doses might be tested in further trials, because their dose-response curves did not plateau.

Relationship Between Plasma Concentrations and Clinical Effects of Cariprazine in Patients With Schizophrenia or Bipolar Mania

Population pharmacokinetic/pharmacodynamic modeling (via NONMEM) was used to describe longitudinal exposure‐response relationships for total cariprazine (sum of cariprazine and its major active metabolites) in 2,558 patients with schizophrenia or bipolar mania. Drug exposure metrics were explored for potential relationships with efficacy and safety end points. Total cariprazine exposures were significantly related to reductions in Positive and Negative Syndrome Scale (PANSS) or Young Mania Rating Scale (YMRS) total scores in schizophrenia or bipolar mania, respectively, via a maximum effect (E_max)‐type relationship. Typical steady‐state plasma concentrations after 3 and 4.5 mg/day were associated with 50% of maximum typical reductions in PANSS and YMRS total scores, respectively. Time‐weighted cariprazine exposures had significant relationships with the probability of common adverse events (AEs). Dose increase was associated with increased efficacy but was also associated with an increase in AEs. Results of these pharmacokinetic/pharmacodynamic analyses support that the recommended dose range (1.5–6 mg/day for schizophrenia and 3–6 mg/day for bipolar mania) provides an appropriate benefit‐risk balance between cariprazine efficacy and safety.

Evaluation of Differences in Individual Treatment Response in Schizophrenia Spectrum Disorders: A Meta-analysis

IMPORTANCE

An assumption among clinicians and researchers is that patients with schizophrenia vary considerably in their response to antipsychotic drugs in randomized clinical trials (RCTs).

OBJECTIVE

To evaluate the overall variation in individual treatment response from random variation by comparing the variability between treatment and control groups.

DATA SOURCES

Cochrane Schizophrenia, MEDLINE/PubMed, Embase, PsycINFO, Cochrane CENTRAL, BIOSIS Previews, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform from January 1, 1955, to December 31, 2016.

STUDY SELECTION

Double-blind, placebo-controlled, RCTs of adults with a diagnosis of schizophrenia spectrum disorders and prescription for licensed antipsychotic drugs.

DATA EXTRACTION AND SYNTHESIS

Means and SDs of the Positive and Negative Syndrome Scale pretreatment and posttreatment outcome difference scores were extracted. Data quality and validity were ensured by following the PRISMA guidelines.

MAIN OUTCOMES AND MEASURES

The outcome measure was the overall variability ratio of treatment to control in a meta-analysis across RCTs. Individual variability ratios were weighted by the inverse-variance method and entered into a random-effects model. A personal element of response was hypothesized to be reflected by a substantial overall increase in variability in the treatment group compared with the control group.

RESULTS

An RCT was simulated, comprising 30 patients with schizophrenia randomized to either the treatment or the control group. The different components of variation in RCTs were illustrated with simulated data. In addition, we assessed the variability ratio in 52 RCTs involving 15 360 patients with a schizophrenia or schizoaffective diagnosis. The variability was slightly lower in the treatment compared with the control group (variability ratio = 0.97; 95% CI, 0.95-0.99; P = .01).

CONCLUSIONS AND RELEVANCE

In this study, no evidence was found in RCTs that antipsychotic drugs increased the outcome variance, suggesting no personal element of response to treatment but instead indicating that the variance was slightly lower in the treatment group than in the control group; although the study cannot rule out that subsets of patients respond differently to treatment, it suggests that the average treatment effect is a reasonable assumption for the individual patient.

Novel antipsychotics specificity profile: A clinically oriented review of lurasidone, brexpiprazole, cariprazine and lumateperone

Second generation antipsychotics (SGAs) are effective options in the treatment of schizophrenia and mood disorders, each with characteristic efficacy and safety features. In order to optimize the balance between efficacy and side effects, it is of upmost importance to match compound specificity against patient clinical profile. As the number of SGAs increased, this review can assist physicians in the prescription of three novel SGAs already on the market, namely lurasidone, brexpiprazole, cariprazine, and lumateperone, which is in the approval phase for schizophrenia treatment at the FDA. Besides schizophrenia, EMA and/or FDA approved lurasidone for bipolar depression, brexpiprazole as augmentation in major depressive disorder and cariprazine for the acute treatment of manic or mixed episodes associated with bipolar I disorder. These new antipsychotics were developed with the aim of improving efficacy on negative and depressive symptoms and reducing metabolic and cardiovascular side effects compared to prior SGAs, while keeping the risk of extrapyramidal symptoms low. They succeeded quite well in containing these side effects, despite weight gain during acute treatment remains a possible concern for brexpiprazole, while cariprazine and lurasidone show higher risk of akathisia compared to placebo and other SGAs such as olanzapine. The available studies support the expected benefits on negative symptoms, cognitive dysfunction and depressive symptoms, while the overall effect on acute psychotic symptoms may be similar to other SGAs such as quetiapine, aripiprazole and ziprasidone. The discussed new antipsychotics represent useful therapeutic options but their efficacy and side effect profiles should be considered to personalize prescription.

Medication-Induced Akathisia with Newly Approved Antipsychotics in Patients with a Severe Mental Illness: A Systematic Review and Meta-Analysis

BACKGROUND

Akathisia is a common and distressing movement disorder that can be associated with the use of antipsychotics. It is characterized by a subjective (inner restlessness) and an objective (excessive movements) component. Akathisia can have a negative impact on clinical outcome and even lead to treatment discontinuation. Although medication-induced akathisia is more commonly associated with the use of first-generation antipsychotics (FGAs), it also occurs with second-generation antipsychotics (SGAs), including the newly approved antipsychotics (NAPs) asenapine, lurasidone, iloperidone, cariprazine, and brexpiprazole. Until now, no meta-analysis has been published on the risk of akathisia for all NAPs, as monotherapy or adjunctive treatment, in patients with a severe mental illness.

OBJECTIVE

The primary objectives of this systematic review and meta-analysis were to (i) compare akathisia incidence rates of the NAPs, as monotherapy or adjunctive treatment, in adult patients with a severe mental illness (i.e., schizophrenia, bipolar disorder, or major depressive disorder), using data from published and unpublished randomized controlled trials; and (ii) examine the role of several study characteristics explaining differences in akathisia incidence rates between studies.

METHODS

A systematic literature search, using the PubMed, EMBASE, and Cochrane Library databases (until October 2018), was conducted for English-language placebo- as well as active-controlled clinical trials, including subjective (percentage of patients reporting akathisia) and/or scale-defined medication-induced akathisia incidence rates with NAPs (as monotherapy or as adjunctive treatment) in adult patients with schizophrenia, bipolar disorder, or major depressive disorder. Additional unpublished clinical trials were identified through the ClinicalTrials.gov electronic database. Two meta-analyses (incidence rates and odds ratio [OR] [placebo vs. active] of medication-induced akathisia with NAPs) were performed to obtain an optimal estimation of akathisia risks of adult patients with a severe mental illness under these treatment conditions and to assess the role of study characteristics.

RESULTS

Two hundred and thirteen reports were selected as potentially eligible for our meta-analysis. Of these, 48 met the inclusion criteria. Eight records, identified through the ClinicalTrials.gov database and cross-referencing, and which fulfilled the inclusion criteria, were added, resulting in a total of 56 records (iloperidone = 5, asenapine = 11, lurasidone = 15, brexpiprazole = 13, cariprazine = 12). The estimated weighted mean incidence rate of akathisia was 7.7% (95% confidence interval [CI] 6.5-9.1), with estimates being 3.9% (95% CI 2.4-6.3) for iloperidone, 6.8% (95% CI 5.1-9.0) for asenapine, 10.0% (95% CI 7.4-13.5) for brexpiprazole, 12.7% (95% CI 10.1-16.1) for lurasidone, and 17.2% (95% CI 13.4-22.1) for cariprazine. After Tukey-adjustment for multiple testing, the incidence rate of akathisia was significantly (p < 0.05) lower for iloperidone than for brexpiprazole, lurasidone, and cariprazine. In addition, the incidence rate of akathisia was significantly (p < 0.05) lower for asenapine than for lurasidone and cariprazine. Finally, the incidence rate of akathisia was significantly (p < 0.05) lower for brexpiprazole than for cariprazine. Type of medication (p < 0.0001), diagnosis (p = 0.02), and race (p = 0.0003) significantly explained part of the heterogeneity of the incidence estimates of akathisia between studies. The estimated weighted OR of akathisia under medication, compared with placebo, was 2.43 (95% CI 1.91-3.10). The OR was smallest for iloperidone (OR 1.20; 95% CI 0.42-3.45) and increased for brexpiprazole (OR 2.04; 95% CI 1.09-3.83), asenapine (OR 2.37; 95% CI 1.32-4.27), lurasidone (OR 3.74; 95% CI 2.32-6.02), and cariprazine (OR 4.35; 95% CI 2.80-6.75). Only type of medication (p = 0.03) explained systematic differences in the OR for akathisia between placebo versus active treatment across studies. After Tukey-adjustment for multiple testing, no significant differences between these ORs were found. The severity of akathisia with NAPs generally is mild to moderate, only leading to treatment discontinuation in a minority of cases (< 5%).

CONCLUSIONS

The use of a NAP raises the akathisia risk more than two-fold when compared with patients receiving placebo. Although distinctions between the different NAPs were not clear in placebo-controlled trials, the results of our meta-analyses and systematic review generally indicate that these differences more than likely reflect real differences, with iloperidone showing the most and cariprazine showing the least benign akathisia profile. Moreover, due to patient characteristics and methodological issues, incidence rates of akathisia with NAPs found in this meta-analysis may even be an underestimation of true incidence rates.

The past and future of novel, non-dopamine-2 receptor therapeutics for schizophrenia: A critical and comprehensive review

Since the discovery of chlorpromazine in the 1950's, antipsychotic drugs have been the cornerstone of treatment of schizophrenia, and all attenuate dopamine transmission at the dopamine-2 receptor. Drug development for schizophrenia since that time has led to improvements in side effects and tolerability, and limited improvements in efficacy, with the exception of clozapine. However, the reasons for clozapine's greater efficacy remain unclear, despite the great efforts and resources invested therewith. We performed a comprehensive review of the literature to determine the fate of previously tested, non-dopamine-2 receptor experimental treatments. Overall we included 250 studies in the review from the period 1970 to 2017 including treatments with glutamatergic, serotonergic, cholinergic, neuropeptidergic, hormone-based, dopaminergic, metabolic, vitamin/naturopathic, histaminergic, infection/inflammation-based, and miscellaneous mechanisms. Despite there being several promising targets, such as allosteric modulation of the NMDA and α7 nicotinic receptors, we cannot confidently state that any of the mechanistically novel experimental treatments covered in this review are definitely effective for the treatment of schizophrenia and ready for clinical use. We discuss potential reasons for the relative lack of progress in developing non-dopamine-2 receptor treatments for schizophrenia and provide recommendations for future efforts pursuing novel drug development for schizophrenia.

Cariprazine for acute and maintenance treatment of adults with schizophrenia: an evidence-based review and place in therapy

Cariprazine is an oral antipsychotic approved in the US and EU for the treatment of schizophrenia. Cariprazine differs from other antipsychotics in that it is a dopamine D3- and D2-receptor partial agonist, with tenfold higher affinity for D3 receptors than for D2 receptors. Cariprazine is metabolized in two steps by CYP3A4 to didesmethyl-cariprazine (DDCAR). DDCAR has a long half-life of 1-3 weeks and is the predominant circulating active moiety. Efficacy and safety in persons with acute schizophrenia were assessed in four similarly designed, short-term, randomized, placebo-controlled clinical trials in nonelderly adults, with three studies considered positive and yielding a number needed to treat vs placebo for response (change from baseline ≥30% in Positive and Negative Syndrome Scale total score) of ten for the approved dose range of cariprazine 1.5-6 mg/day. The most common adverse reactions were extrapyramidal symptoms (15% and 19% for 1.5-3 and 4.5-6 mg/day, respectively, vs 8% for placebo) and akathisia (9% and 12.5% for 1.5-3 and 4.5-6 mg/day, respectively, vs 4% for placebo). For the approved dose range, rates of discontinuation because of an adverse event were lower overall for patients receiving cariprazine vs placebo (9% vs 12%). Weight and metabolic profile appear favorable. Cariprazine does not increase prolactin levels or prolong the electrocardiographic QT interval. Cariprazine has also been found to be effective for the maintenance treatment of schizophrenia by delaying time to relapse when compared with placebo (HR 0.45). A 26-week randomized clinical trial evidenced superiority of cariprazine over risperidone for the treatment of predominantly negative symptoms in patients with schizophrenia. Cariprazine is also approved in the US for the acute treatment of manic or mixed episodes associated with bipolar I disorder in adults and is being studied for the treatment of bipolar I depression and major depressive disorder.

Review of cariprazine in management of psychiatric illness

Schizophrenia and bipolar disorder are severe and debilitating psychiatric disorders. Despite the availability of numerous antipsychotic drugs, many patients still experience poor outcomes and treatment-limiting adverse side effects. Cariprazine is a novel antipsychotic with unique pharmacodynamic and pharmacokinetic properties. It is both a dopamine type 2 and dopamine type 3 partial agonist with 2 equipotent metabolites, desmethyl cariprazine and didesmethyl cariprazine, of which didesmethyl cariprazine has a half-life of 1 to 3 weeks. The objective of this article is to review the literature regarding efficacy and tolerability of cariprazine in the management of psychiatric disorders to determine its current place in therapy.

Efficacy and Acceptability of Cariprazine in Acute Exacerbation of Schizophrenia: Meta-Analysis of Randomized Placebo-Controlled Trials

PURPOSE

The purpose of this study was to assess the efficacy and acceptability of cariprazine treatment in acute exacerbation of schizophrenia.

METHODS

This review included randomized controlled trials of patients with acute exacerbation of schizophrenia in relation to efficacy and acceptability. The efficacy outcomes were assessed by pooling standardized mean differences (SMDs) calculated from the difference in the reduction in the mean of the Positive and Negative Syndrome Scale (PANSS) total score, PANSS positive and negative scores, and response rate. The primary acceptability outcomes were determined by pooling the risk ratios (RRs) of discontinuation for any reason, the incidence of serious adverse events, and treatment emergent events.

FINDINGS

Four randomized controlled trials consisting of 1843 patients met all inclusion and exclusion criteria. Efficacy analysis showed significant positive effects in relation to cariprazine therapy (SMD: -0.37, P < 0.00001 for PANSS total score change; SMD: -0.32, P < 0.00001 for PANSS positive score change; SMD: -0.32, P < 0.0001 for PANSS negative score change; RR, 1.41; 95% confidence interval [CI], 1.19-1.67; P < 0.0001 for response rate). For primary acceptability outcomes, less patients taking cariprazine discontinued treatment for any reason compared with patients receiving placebo (RR, 0.90; 95% CI, 0.78-1.04; P = 0.16). Significantly less patients on cariprazine had serious adverse events during the double-blind treatment period compared with patients taking placebo (RR, 0.55; 95% CI, 0.34-0.89; P = 0.01). Significantly more patients on cariprazine had treatment emergent events compared with those receiving placebo (RR, 1.10; 95% CI, 1.03-1.18; P = 0.006).

IMPLICATIONS

Results suggest that cariprazine may be an effective and acceptable treatment for schizophrenia and future research is warranted.

Global improvement with cariprazine in the treatment of bipolar I disorder and schizophrenia: A pooled post hoc analysis

INTRODUCTION

Global rating scale measures are useful for assessing the clinical relevance of patient change. Cariprazine, a dopamine D₃ and D₂ receptor partial agonist, is FDA-approved for the adult treatment of acute manic/mixed episodes of bipolar I disorder and schizophrenia. Post hoc evaluations of Clinical Global Impressions-Severity (CGI-S) scores from the cariprazine pivotal trials in both indications were conducted.

METHODS

Data from 3 bipolar mania and 3 schizophrenia trials were pooled by indication (bipolar disorder = 1033; schizophrenia = 1466). Cariprazine- and placebo-treated patients were categorised by baseline CGI-S scores; the proportion of patients who improved from more severe categories at baseline to less severe categories at end-point was evaluated using a logistic regression model. Correlations between Young Mania Rating Scale and Positive and Negative Syndrome Scale total score changes and category shifts were also evaluated.

RESULTS

In both disease states, more cariprazine- than placebo-treated patients had improved CGI-S scores at end-point; more placebo-treated patients had worse end-point scores. More cariprazine- vs placebo-treated patients shifted from the extremely/severely ill to mildly ill/better category (bipolar disorder = 55% vs 36%, odds ratio [OR] = 2.1; P = .09; schizophrenia = 42% vs 18%, OR = 3.4, P<.01). ORs was statistically significant in favour of cariprazine in shifts from marked and moderate illness to borderline/normal in both indications (P < .05). Correlations between rating scale improvement and category shift were greatest in patients with extreme/severe baseline illness for bipolar disorder (-0.853) and schizophrenia (-0.677).

CONCLUSIONS

Post hoc analyses showed that more cariprazine- than placebo-treated patients with bipolar mania or schizophrenia had statistically significant and clinically meaningful CGI-S improvement.

Safety and tolerability of cariprazine in patients with acute exacerbation of schizophrenia: a pooled analysis of four phase II/III randomized, double-blind, placebo-controlled studies

Cariprazine, a potent dopamine D3 and D2 receptor partial agonist antipsychotic with preferential binding to D3 receptors, is Food and Drug Administration approved for treating schizophrenia and manic or mixed episodes of bipolar I disorder. A post-hoc safety/tolerability analysis of data from the four acute trials in the cariprazine schizophrenia clinical development program (NCT00404573; NCT00694707; NCT01104766; NCT01104779) was carried out using the overall safety population (all patients who received ≥1 dose of study drug) and modal daily dose subgroups (1.5-3, 4.5-6, and 9-12 mg/day). These exploratory findings were summarized using descriptive statistics. Cariprazine was generally well tolerated. The incidence of treatment-emergent adverse events versus placebo was similar for cariprazine 1.5-3 mg/day and higher for cariprazine 4.5-6 and 9-12 mg/day; a dose-response relationship was observed for akathisia, extrapyramidal symptoms, and diastolic blood pressure. The mean changes in metabolic parameters were generally similar in cariprazine-treated and placebo-treated patients. There was no prolactin level increase or QTc value greater than 500 ms; small increases in mean body weight (∼1to2 kg) versus placebo were observed. Within the Food and Drug Administration-approved dose range (1.5-6 mg/day), cariprazine was generally safe and well tolerated in patients with schizophrenia.

Cariprazine specificity profile in the treatment of acute schizophrenia: a meta-analysis and meta-regression of randomized-controlled trials

Cariprazine is a new dopamine D2 and D3 receptor partial agonist antipsychotic. Meta-analytic evidence of efficacy in acute schizophrenia and specific groups of patients is lacking. We carried out a meta-analysis in patients with acute schizophrenia to evaluate the efficacy of cariprazine over placebo and active comparators in overall symptoms, positive and negative symptoms and quality of life. Low and high (≥6 mg/day) doses were tested separately. The possible effect of clinical-demographic modulators was also tested. Four studies (2144 patients) were included. Both high and low cariprazine doses proved superior to placebo in all symptom domains. The standardized mean difference (SMD) to placebo showed a modest impact on overall symptoms compared with meta-analytic results for other antipsychotics (SMD was similar to lurasidone, asenapine, ziprasidone and aripiprazole, but lower than risperidone, quetiapine and olanzapine). The SMD to placebo on negative symptoms was superior to many antipsychotics including aripiprazole, with a slightly more relevant effect of cariprazine low doses. This effect was probably on secondary negative symptoms since the short-term follow-up of the studies included. Meta-regression data further refined the compound clinical profile, suggesting that cariprazine may be particularly useful in young patients with a relatively short duration of disease.

Cariprazine: A Review in Schizophrenia

Cariprazine (Vraylar™) is a dopamine D₃-preferring D₂/D₃ receptor partial agonist indicated for the treatment of patients with schizophrenia. This narrative review summarizes pharmacological, efficacy and tolerability data relevant to the use of cariprazine in patients with this disorder. In 6-week, phase IIb and III trials in patients with schizophrenia, cariprazine was significantly more efficacious than placebo in improving schizophrenia symptoms, including improvements in Positive and Negative Syndrome Scale (PANSS) total scores. It was associated with a significantly longer time to relapse than placebo in a long-term, phase III, relapse-prevention study. Cariprazine was also significantly more efficacious than risperidone in improving PANSS Factor Score for Negative Symptoms in a phase III trial in patients with predominantly negative symptoms of schizophrenia, a typically difficult to treat group of patients. Cariprazine was generally well tolerated in clinical trials, with most adverse events being of mild to moderate severity, and metabolic changes observed were considered generally not clinically significant. Cariprazine is a useful addition to the treatment options for schizophrenia, and may be of particular use in patients with predominantly negative symptoms.

Activating and Sedating Adverse Effects of Second-Generation Antipsychotics in the Treatment of Schizophrenia and Major Depressive Disorder: Absolute Risk Increase and Number Needed to Harm

PURPOSE/BACKGROUND

Activating and sedating adverse effects of antipsychotics can be obstacles to their use.

METHODS/PROCEDURES

This study quantified the activating and sedating properties of first-line oral second-generation antipsychotics by examining the rates of adverse reactions as reported in product labeling for the indications of schizophrenia and adjunctive treatment of major depressive disorder. Additional data sources included regulatory documents, study synopses, and published study reports. Attributable risk increase and number needed to harm (NNH) were calculated for each agent versus placebo.

FINDINGS/RESULTS

Heterogeneity among the different antipsychotics regarding activating or sedating adverse events was observed, with some agents displaying the potential for both activating and sedating properties. For agents indicated for the treatment of schizophrenia, predominantly activating medications include lurasidone (NNH, 11 for akathisia vs 20 for somnolence) and cariprazine (NNH, 15 for akathisia vs 65 for somnolence-combined terms). Similarly activating and sedating are risperidone (NNH, 15 for akathisia vs 13 for sedation) and aripiprazole (NNH, 31 for akathisia vs 34 for somnolence). Predominantly sedating are olanzapine, quetiapine immediate and extended release, ziprasidone, asenapine, and iloperidone. Agents that are neither activating nor sedating are paliperidone and brexpiprazole. For major depressive disorder, the overall findings regarding activation and sedation appear similar to those seen with schizophrenia. Data extracted were limited to those available from registrational studies that contributed to the adverse event tables contained in the product labels. Postregistrational comparative studies may yield different outcomes.

IMPLICATIONS/CONCLUSIONS

Differences in tolerability profiles regarding activation and sedation have implications in terms of selecting the optimal antipsychotic for a given individual.

Tolerability and Safety Profile of Cariprazine in Treating Psychotic Disorders, Bipolar Disorder and Major Depressive Disorder: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Cariprazine is a novel antipsychotic agent recently approved for treating schizophrenia and bipolar mania in the USA. The sample sizes of published randomized controlled trials (RCTs) of the drug are small; previous meta-analyses included few RCTs and did not specifically investigate the tolerability/safety profile of cariprazine.

OBJECTIVE

Our objective was to conduct a meta-analysis of published RCTs to systematically review the tolerability and safety of cariprazine versus placebo.

METHODS

We searched the clinical trial registers (the metaRegister of controlled trials, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform) and electronic databases (PubMed, Embase, PsycINFO and Cochrane library) up to June 2016 to identify phase II/III RCTs of cariprazine in patients with schizophrenia, bipolar disorder or major depressive disorder. We conducted a meta-analysis to investigate outcomes, including risks of discontinuation due to adverse events (AEs), extrapyramidal side effects (EPS) or related events, metabolic syndrome and cardiovascular-related events.

RESULTS

We included nine RCTs, with a total of 4324 subjects. The risk of discontinuation due to AEs for cariprazine was similar to that for placebo (risk ratio [RR] 1.13, 95 % confidence interval [CI] 0.77-1.66). Cariprazine was associated with higher risks of EPS-related events than was placebo, including risk of akathisia (RR 3.92, 95 % CI 2.83-5.43), tremor (RR 2.41, 95 % CI 1.53-3.79) and restlessness (RR 2.17, 95 % CI 1.38-3.40). The cariprazine treatment group was more likely to have clinically significant weight gain (RR 1.68, 95 % CI 1.12-2.52). No statistically significant differences in results were found in other metabolic parameters or cardiovascular-related events.

CONCLUSION

There was a statistically significant higher risk of EPS-related AEs and a slight increase in mean body weight with cariprazine. There were no statistically significant effects on prolactin level or cardiovascular parameters. EPSs were the main short-term adverse reactions reported in the limited number of patients studied. Further clinical and post-marketing pharmacovigilance studies are needed to investigate the long-term safety of cariprazine.

Dopamine D3 Receptor Antagonists as Potential Therapeutics for the Treatment of Neurological Diseases

D3 receptors represent a major focus of current drug design and development of therapeutics for dopamine-related pathological states. Their close homology with the D2 receptor subtype makes the development of D3 selective antagonists a challenging task. In this review, we explore the relevance and therapeutic utility of D3 antagonists or partial agonists endowed with multireceptor affinity profile in the field of central nervous system disorders such as schizophrenia and drug abuse. In fact, the peculiar distribution and low brain abundance of D3 receptors make them a valuable target for the development of drugs devoid of motor side effects classically elicited by D2 antagonists. Recent research efforts were devoted to the conception of chemical templates possibly endowed with a multi-target profile, especially with regards to other G-protein-coupled receptors (GPCRs). A comprehensive overview of the recent literature in the field is herein provided. In particular, the evolution of the chemical templates has been tracked, according to the growing advancements in both the structural information and the refinement of the key pharmacophoric elements. The receptor/multireceptor affinity and functional profiles for the examined compounds have been covered, together with their most significant pharmacological applications.