Effect of Brexpiprazole on Prolactin: An Analysis of Short- and Long-Term Studies in Schizophrenia

Differentiating the third generation of antipsychotics: a focus on lumateperone's similarities and differences

The development of atypical antipsychotics has evolved to include newer pharmacodynamic properties. Lumateperone, aripiprazole, brexpiprazole, and cariprazine are all dopamine-2 receptor partial agonists with varying receptor affinities. This review aims to compare the clinical and pharmacodynamic differences among these four atypical antipsychotics, all of which are unique when compared to first- and second-generation antipsychotics. For consideration is further delineating these agents as being third-generation antipsychotics. PubMed searches were conducted to compile preclinical and clinical studies derived from animal models and human subjects. Information gathered included pharmacological mechanisms, clinical efficacy, future-oriented clinical approaches, and adverse effects. Efficacy for the shared indications of these drugs seems comparable. Differences among these drugs lie more in their adverse effect profiles. For example, lumateperone was found to have the lowest rate of weight gain while brexpiprazole was found to have the highest rate of weight gain associated with increased appetite. Aripiprazole had the lowest rates of extrapyramidal symptoms not including akathisia while cariprazine had the highest. All four agents reviewed have a variety of receptor affinities, which likely generates a variety of different adverse effects. This suggests that in any given patient, clinicians may see differential clinical effects.

Managing antipsychotic-related sexual dysfunction in patients with schizophrenia

INTRODUCTION

Schizophrenia is a psychotic disorder and one of the most severe and impactful mental illnesses. Sexual dysfunction is highly prevalent in patients with schizophrenia but remains underdiagnosed and undertreated. Sexual dysfunction is frequently attributed to antipsychotics which may reduce medication adherence, but negative symptoms can also reduce sexual drive.

AREAS COVERED

This review provides an overview of the current knowledge about sexual dysfunction in patients with schizophrenia. The authors first review the literature concerning the mechanisms of sexual dysfunction and explore the impact of antipsychotics on sexual function. Finally, they present the available non-pharmacological and pharmacological treatment strategies for sexual dysfunction in patients with schizophrenia.

EXPERT OPINION

Sexual dysfunction in patients with schizophrenia is still underrated by clinicians despite having a negative impact on the quality of life and therapeutic adherence. Antipsychotic treatment is still perceived as a major cause of sexual impairment. Psychiatrists must be aware of this condition and actively question the patients. A comprehensive approach, addressing pharmacological and non-pharmacological aspects, is fundamental for managing sexual dysfunction in schizophrenia. Pharmacological strategies include (1) Serum-level adjustment of the antipsychotic dose, if possible (2) switching to a well-tolerable antipsychotic (aripiprazole, brexpiprazole) and (3) adding a coadjuvant drug (phosphodiesterase-5 inhibitors).

Brexpiprazole—Pharmacologic Properties and Use in Schizophrenia and Mood Disorders

In 2002, the first III generation antipsychotic drug was registered—aripiprazole. Its partial dopaminergic agonism underlies its unique mechanism of action and the potentially beneficial influence on the positive, negative, or cognitive symptoms. Due to its relatively high intrinsic activity, the drug could often cause agitation, anxiety, or akathisia. For this reason, efforts were made to develop a drug which would retain the positive favorable actions of aripiprazole but present a more advantageous clinical profile. This turned out to be brexpiprazole, which was registered in 2015. Its pharmacodynamic and pharmacokinetic profile (similarly to the other most recent antipsychotics, i.e., lurasidone or cariprazine) shows promise of increasing the effectiveness of schizophrenia treatment in the dimensions in which the previous antipsychotics were not sufficiently effective, including negative, depressive, or cognitive symptoms. Like other new antipsychotics, it can also be useful in the treatment of mood disorders, for instance drug-resistant depression. Previous reviews focused on the use of brexpiprazole in specific diagnostic groups. The aim of this article is to provide the readers with an overview of data on the mechanism of action, clinical effectiveness in all studied diagnostic groups, as well as potential drug–food interactions, and the safety of brexpiprazole.

Pharmacological strategies for sexual recovery in men undergoing antipsychotic treatment

INTRODUCTION

: First- and second-generation antipsychotics are highly accountable for causing a plethora of medical side effects, ranging from metabolic imbalances to sexual dysfunction (SD), that frequently undermine patient-doctor relationships. Nevertheless, to date antipsychotics are one of the best treatment options for dealing with numerous either acute or chronic conditions like agitation, suicidality, depression, dementia, and of course psychosis. For these reasons, clinicians need to handle them wisely to preserve patients' sexual health, avoid poor therapeutic adherence and prevent high rates of therapy drop-out.

AREAS COVERED

: This article reviews the literature on pharmacologic approaches for management strategies in men who are administered with antipsychotics and developed SD. The etiology of antipsychotic-induced SD is also discussed.

EXPERT OPINION

: Clinicians must consider sexual life as a major health domain. To do so, a first step would be to measure and monitor sexual function by means of psychometric tools. Secondly, primary prevention should be conducted when choosing antipsychotics, i.e., picking sex-sparing compounds like aripiprazole or brexpiprazole. Thirdly, if sexolytic compounds cannot be dismissed, such as first-generation antipsychotics, risperidone, paliperidone, or amisulpride, then aripiprazole 5-20 mg/day adjunctive therapy has proven to be most effective in normalizing prolactin levels and consequently treating antipsychotic-induced SD.

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.

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.

Discovery research and development history of the dopamine D2 receptor partial agonists, aripiprazole and brexpiprazole

Otsuka Pharmaceutical Co., Ltd. successfully developed the first dopamine D₂ receptor partial agonist approved for schizophrenia, the antipsychotic aripiprazole (Abilify^®). The drug was approved for this indication in the United States in 2002 and has received approval in the United States, Europe, Japan, and many other countries for several indications including schizophrenia, acute mania, adjunctive treatment of major depressive disorder (MDD), irritability associated with autistic disorder, and Tourette's disorder. Otsuka next developed brexpiprazole (Rexulti^®), another D₂ receptor partial agonist, which was granted marketing approval in the United States in 2015 as adjunctive therapy in major depressive disorder and for the treatment of schizophrenia. In Japan, brexpiprazole also received approval as a treatment for schizophrenia in 2018. In this review, we describe Otsuka's research history and achievements over the preceding 40 years in the area of antipsychotic drug discovery for dopamine D₂ receptor partial agonists.

“Dopamine‐system stabilizer” activity of aripiprazole.

Guidance on the treatment of antipsychotic-induced hyperprolactinemia when switching the antipsychotic is not an option

Disclaimer

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Purpose

This article aims to evaluate management options for antipsychotic-induced hyperprolactinemia and associated treatment considerations such as efficacy, tolerability, drug interactions, contraindications, and dosing regimens.

Summary

Hyperprolactinemia is a common adverse effect of antipsychotics. First-line management includes reducing the dose of the offending antipsychotic, discontinuing the antipsychotic, or switching to another antipsychotic associated with a lower risk of hyperprolactinemia. However, these options are not always practical and are associated with a risk of relapse of the psychiatric illness. Other management options include adjunctive aripiprazole, dopamine agonists (cabergoline and bromocriptine), metformin, and herbal supplements. A search of Embase, PubMed, and Google Scholar using key terms such as hyperprolactinemia, prolactin, antipsychotic, treatment guidelines, aripiprazole, dopamine agonist, cabergoline, bromocriptine, metformin, herbals, supplements, and medications was conducted for literature retrieval. Upon evaluation of the available literature we found the following: (1) aripiprazole is safe and effective in lowering prolactin levels within normal limits; (2) adjunctive cabergoline and bromocriptine decrease elevated prolactin levels, while cabergoline may be more effective in reducing prolactin but can also be associated with a more serious adverse effect of cardiac valvular abnormalities; (3) metformin causes a mild reduction of prolactin levels; and (4) there are limited data to support use of herbal medications (chamomile, Peony-Glycyrrhiza decoction, and shakuyaku-kanzo-to) in antipsychotic-induced hyperprolactinemia

Conclusion

There are treatments available for antipsychotic-induced hyperprolactinemia in patients who are unable to alter their current antipsychotic regimen. However, there remains a need for additional short- and long-term studies to determine the efficacy and safety of these treatment strategies, given that patients taking antipsychotics typically require chronic, life-long treatment for their illnesses.

Management Strategies for Antipsychotic-Related Sexual Dysfunction: A Clinical Approach

Antipsychotic medication can be often associated with sexual dysfunction (SD). Given its intimate nature, treatment emergent sexual dysfunction (TESD) remains underestimated in clinical practice. However, psychotic patients consider sexual issues as important as first rank psychotic symptoms, and their disenchantment with TESD can lead to important patient distress and treatment drop-out. In this paper, we detail some management strategies for TESD from a clinical perspective, ranging from prevention (carefully choosing an antipsychotic with a low rate of TESD) to possible pharmacological interventions aimed at improving patients' tolerability when TESD is present. The suggested recommendations include the following: prescribing either aripiprazole or another dopaminergic agonist as a first option antipsychotic or switching to it whenever possible. Whenever this is not possible, adjunctive treatment with aripiprazole seems to also be beneficial for reducing TESD. Some antipsychotics, like olanzapine, quetiapine, or ziprasidone, have less impact on sexual function than others, so they are an optimal second choice. Finally, a variety of useful strategies (such as the addition of sildenafil) are also described where the previous ones cannot be applied, although they may not yield as optimal results.

Sexuality in Ultra-High Risk for Psychosis and First-Episode Psychosis. A Systematic Review of Literature

A considerable body of literature reports that individuals with psychotic disorders often suffer from sexual dysfunctions (SDs), with these representing a major unmet need. Long-term antipsychotic drug treatment may be the main cause for SDs in psychotic patients, through a plethora of different mechanisms, including prolactin dyscrasia, histamine-mediated sedation, and serotonin-induced sexual demotivation. However, a few pieces of evidence treat sexuality in patients at risk or the onset of psychosis. For this purpose, we systematically reviewed literature of the last 10 years in order to investigate sexuality in ultra-high risk (UHR) for psychosis and first-episode psychosis (FEP). We included in our review 34 articles fitting our research criteria on SDs in UHR and FEP. Evidence of SDs in the transition from UHR to FEP emerges through the selected studies. In FEP, sexuality is affected by the severity of the psychotic symptoms and, in some cases, by the iatrogenic effects of psychopharmacological treatment. Further experimental and clinical studies should systematically investigate the role of sexual functioning in the transition from UHR to FEP and, consequently, clarify whether or not SDs could be considered a possible marker for the onset of psychosis in at-risk populations. Moreover, psychiatrists and clinical psychologists should take into consideration the role of sexual life in young people with prodromal mental symptoms or at the onset of psychosis. Focusing on a thorough sexual evaluation might be a major challenge that could break down barriers of mental health promotion among young people with schizophrenia-spectrum disorders and therefore achieve better clinical outcomes.

Brexpiprazole for the Treatment of Schizophrenia in Adults: An Overview of Its Clinical Efficacy and Safety and a Psychiatrist's Perspective

While the prognosis of patients with schizophrenia has dramatically improved after the advent of chlorpromazine, the antipsychotics currently available are so numerous that it has become a challenge for psychiatrists to choose from among these drugs for each patient presenting for care. In addition, while numerous studies show that an effective antipsychotic should be continued indefinitely to prevent relapses or worsening, many patients appear to have difficulty remaining on any drug thus initiated. Brexpiprazole, a dopamine D₂ receptor partial agonist, appears to provide a unique profile that has much to offer in this light. Specifically, this novel drug is potentially better suited for long-term use, with decreased risk of extrapyramidal side effects, hyperprolactinemia, weight gain, psychosis, insomnia, akathisia, nausea/vomiting or restlessness, thus potentially facilitating patients' reintegration into society. Indeed, brexpiprazole has been shown in randomized, double-blind, placebo-controlled trials to have proven efficacy not only in improving the symptoms of schizophrenia but in preventing relapses. It is also suggested in both short- and long-term studies that brexpiprazole offers a favorable safety and tolerability profile. This review also includes a proposed treatment algorithm incorporating brexpiprazole, based on the clinical trial results available, as well as on the authors' clinical experience, where brexpiprazole may be best used as a drug of first choice for the treatment of schizophrenia. Thus, overall, brexpiprazole appears to play a more significant role in the treatment of schizophrenia than other antipsychotics.

Up-to-date expert opinion on the safety of recently developed antipsychotics

Introduction There are several new and emerging antipsychotic medication strategies recently marketed or under clinical development for the treatment of several mental disorders. There is the need to provide an up-to-date overview on the safety of this new generation of antipsychotic medications, which includes also the third-generation antipsychotics (TGA). Areas covered The authors aimed at providing a synthesis of the most current evidence about the safety profile of the recently developed and/or marketed antipsychotics. Qualitative synthesis followed an electronic search made inquiring of the following databases: MEDLINE, Embase, PsycINFO, and the Cochrane Library from inception until March 2020, combining free terms and MESH headings for the topics of TGA and recently developed and/or marketed antipsychotics as following: ((safety OR adverse events OR side effects) AND ((brexpiprazole OR cariprazine OR inhaled loxapine OR lumateperone (ITI-007) OR lurasidone OR pimavanserin OR roluperidone (MIN-101) OR transdermal patch asenapine)). Expert opinion Overall, newer antipsychotics display a good safety profile, with a well-demonstrated lower metabolic liability compared to second-generation antipsychotics. Furthermore, TGA appear to specifically target negative symptomatology and improving cognitive domains. Abbreviations Aps=Antipsychotic Drugs; AEs = Adverse Effects; EPS = Extrapyramidal Symptoms; NMS = Neuroleptic malignant syndrome; D = Dopamine; K_i = Inhibitory Constant; 5-HT = Serotonin; ECG = Electrocardiogram; H = Histamine; M = Muscarinic; BMI = Body Mass Index.

Brexpiprazole in the treatment of schizophrenia and agitation in Alzheimer's disease

Schizophrenia is a disabling psychiatric disorder marked by progressive loss of functionality in activities of daily living with each relapse. Antipsychotics, the mainstay of therapy for schizophrenia, treat hallucinations and delusions but may have intolerable side effects, including metabolic disturbances and extrapyramidal symptoms. Brexpiprazole, a second-generation antipsychotic with dopamine partial agonist properties, was approved by the US FDA in 2015 for the treatment of schizophrenia and adjunctive treatment of major depressive disorder and by the EU in 2018 for adults with schizophrenia. Additionally, brexpiprazole has recently been studied for the treatment of agitation in Alzheimer's dementia, an area of largely unmet need. Overall, well-tolerated brexpiprazole expands the armamentarium of treatment options available for these conditions.

Comparative Tolerability of Dopamine D2/3 Receptor Partial Agonists for Schizophrenia

Aripiprazole, brexpiprazole and cariprazine differ from all other second-generation antipsychotics due to partial agonism at the dopamine D2 and D3 receptors. In contrast to aripiprazole, brexpiprazole has lower intrinsic dopamine D2 activity and higher affinity for the serotonin 5-HT1A and 5-HT2A receptors, while cariprazine has the highest affinity for the dopamine D3 receptor, and the longest half-life. The main adverse effect of dopamine receptor partial agonists (DRPAs) is akathisia of low-to-moderate severity, which occurs in a small proportion of patients, usually in the first few weeks of treatment. While definitive conclusions concerning differences between the DRPAs require head-to-head comparison studies, on the available evidence, akathisia is probably least likely to occur with brexpiprazole and most likely with cariprazine; the risk of akathisia with aripiprazole lies in between. Weight-gain risk is low with aripiprazole and cariprazine, but moderate with brexpiprazole. Risk of sedation is low with DRPAs, as is risk of insomnia and nausea. Partial dopamine agonism leads to a low risk for hyperprolactinaemia (and probably a low risk of sexual dysfunction). Prolactin concentrations fall in some patients (particularly those with elevated levels prior to initiating the drugs). Rates of discontinuation due to adverse effects in pivotal studies were low, and on the whole, DRPAs are well tolerated. Aripiprazole has been implicated in pathological gambling and other impulse control behaviours, likely due to partial dopamine agonist activity (there have been no reports with brexpiprazole and cariprazine). The risks for diabetes and tardive dyskinesia with DRPAs are unknown, but are likely to be low. On the basis of tolerability, DRPAs should be considered as first-line treatment options, particularly in patients with early schizophrenia.

Effect of Brexpiprazole on Prolactin and Sexual Functioning: An Analysis of Short- and Long-Term Study Data in Major Depressive Disorder

PURPOSE/BACKGROUND

Evidence supports use of adjunctive atypical antipsychotics in major depressive disorder (MDD). Impaired sexual functioning is common in MDD and may be worsened by antipsychotic adverse effects. We evaluated the effect of brexpiprazole on prolactin and sexual functioning in patients with MDD.

METHODS/PROCEDURES

In short-term studies, patients received adjunctive brexpiprazole 1, 2, or 3 mg or placebo. The long-term study was a flexible-dose (0.5-3 mg/d) open-label extension (OLE). Change from baseline and shifts in prolactin status and prolactin-related treatment-emergent adverse events (TEAEs) were assessed. Sexual functioning was assessed by the Massachusetts General Hospital Sexual Functioning Questionnaire.

FINDINGS/RESULTS

Median changes in prolactin levels from baseline to week 6 in short-term studies were as follows: brexpiprazole, 5.99 ng/mL (females) and 1.61 ng/mL (males); placebo, -0.15 ng/mL (females) and -0.08 ng/mL (males).Median changes from baseline to week 52 in the OLE were as follows: 0.27 ng/mL (females) and 0.27 ng/mL (males). Prolactin levels in patients with baseline prolactin greater than 1× upper limit of normal values tended to decrease over time.The proportion of brexpiprazole-treated patients with greater than 3× upper limit of normal postbaseline prolactin values in short-term studies for both sexes was low (0%-0.3%) and did not differ from placebo: OLE, 0.5% (females) and 0.8% (males).In short-term studies, the incidence of prolactin-related TEAEs was 3.1% for brexpiprazole and 0.7% for placebo (OLE, 3.1%). There were overall numerical improvements from baseline in sexual functioning for females and males after short- and long-term brexpiprazole treatment, with statistically significant improvements for brexpiprazole versus placebo in females on the items 'interest in sex' (-0.19; 95% confidence interval [CI], -0.33 to -0.05; P = 0.0074), 'sexually aroused' (-0.17; 95% CI, -0.30 to -0.03; P = 0.0154), and 'overall sexual satisfaction' (-0.16; 95% CI, -0.30 to -0.03; P = 0.0184).

IMPLICATIONS/CONCLUSIONS

There were small changes in prolactin levels, low proportions of patients with postbaseline elevated prolactin values, low incidences of prolactin-related TEAEs, and modest improvements in sexual functioning with adjunctive brexpiprazole in MDD.

Brexpiprazole: A Review in Schizophrenia

Brexpiprazole (Rxulti^®, Rexulti^®) is an oral atypical antipsychotic agent approved for the treatment of schizophrenia in the EU (in adult patients) and the USA, as well as in some other countries, including Japan. Like aripiprazole, it is a partial agonist at dopamine D₂ and serotonin 5-HT_1A receptors and an antagonist at serotonin 5-HT_2A receptors. However, brexpiprazole displays less intrinsic activity at D₂ receptors and, coupled with actions at 5HT_1A, 5HT_2A and noradrenaline α_1B receptors that are at least as potent as its action at D₂ receptors, is predicted to demonstrate a lower propensity for activating adverse events and extrapyramidal symptoms than aripiprazole. Brexpiprazole 2-4 mg/day produced statistically significant and clinically meaningful improvements in overall symptomatology and psychosocial functioning compared with placebo in adults with acute exacerbation of schizophrenia. As maintenance treatment, brexpiprazole 1-4 mg/day significantly delayed the time to relapse compared with placebo in patients who were already stabilized on the drug and was associated with stabilization or continued improvement in patients' symptoms and functioning. Brexpiprazole was generally well tolerated, exhibiting an adverse event profile characterized by a relatively low incidence of activating and sedating adverse effects, small changes in QT interval and metabolic parameters that were not clinically significant, and moderate weight gain. Clinical evidence to date suggests it usefully extends the range of therapeutic options for schizophrenia.

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

The purpose of this review is to describe the available data for brexpiprazole in the maintenance treatment of schizophrenia. This objective was completed by searching the databases PubMed, Embase, and ClinicalTrials.gov to identify relevant study results presented as papers or abstracts. In summary, brexpiprazole is a new agent in the D₂ partial agonist class that has a unique receptor-binding profile, based in part on high affinity for serotonin 5HT_1A and 5HT_2A receptors, paired with lower intrinsic activity at dopamine D₂ receptors. The average dose used in efficacy and safety studies for the maintenance treatment of schizophrenia ranged from 3.0 and 3.1 mg in the open-label safety studies to 3.6 mg in the double-blind randomized relapse-prevention study. Highlights from the 52-week double-blind placebo-controlled relapse-prevention trial evidenced rates of relapse in the brexpiprazole group of 13.5% vs 38.5% in the placebo group (number needed to treat 4, 95% CI 3-8; P<0.0001). Safety data indicate that brexpiprazole is tolerated well, with rates of discontinuation due to treatment-emergent adverse events that ranged from 5.2% of those taking brexpiprazole in the double-blind maintenance phase of the relapse-prevention trial to 15.3% in a 52-week open-label safety study. In the available trials, there were relatively low rates of akathisia, and the degree of weight gain was similar to that seen in studies with aripiprazole for the treatment of schizophrenia. Positive and Negative Syndrome Scale scores also remained relatively stable in the open-label safety studies. Available data indicate that brexpiprazole is an effective agent for the maintenance treatment of schizophrenia that is overall well tolerated.