The management of schizophrenia: focus on extended-release quetiapine fumarate

The dilemma of polypharmacy in psychosis: is it worth combining partial and full dopamine modulation?

Antipsychotic polypharmacy in psychotic disorders is widespread despite international guidelines favoring monotherapy. Previous evidence indicates the utility of low-dose partial dopamine agonist (PDAs) add-ons to mitigate antipsychotic-induced metabolic adverse effects or hyperprolactinemia. However, clinicians are often concerned about using PDAs combined with high-potency, full dopaminergic antagonists (FDAs) due to the risk of psychosis relapse. We, therefore, conducted a literature review to find studies investigating the effects of combined treatment with PDAs (i.e. aripiprazole, cariprazine and brexpiprazole) and FDAs having a strong D 2 receptor binding affinity. Twenty studies examining the combination aripiprazole - high-potency FDAs were included, while no study was available on combinations with cariprazine or brexpiprazole. Studies reporting clinical improvement suggested that this may require a relatively long time (~11 weeks), while studies that found symptom worsening observed this happening in a shorter timeframe (~3 weeks). Patients with longer illness duration who received add-on aripiprazole on ongoing FDA monotherapy may be at greater risk for symptomatologic worsening. Especially in these cases, close clinical monitoring is therefore recommended during the first few weeks of combined treatment. These indications may be beneficial to psychiatrists who consider using this treatment strategy. Well-powered randomized clinical trials are needed to derive more solid clinical recommendations.

Real-World Economic Outcomes of Brexpiprazole and Extended-Release Quetiapine Adjunctive Use in Major Depressive Disorder

Purpose

Major depressive disorder (MDD) is a chronic mental disorder with a substantial clinical and economic burden. Despite the efficacy of adjunctive atypical antipsychotics (AAP) for augmentation in patients with major depressive disorder (MDD) who failed first-line antidepressant therapy (ADT), little is known of the impact of AAP choices on healthcare resource use and costs in real-world practice. Therefore, this study compared real-world healthcare utilization and costs in patients with MDD treated with brexpiprazole or extended-release (XR) quetiapine as adjunctive treatment to ADT.

Patients and methods

Adults with MDD starting adjunctive treatment with brexpiprazole (n=844) or extended-release (XR) quetiapine (n=688) were identified in the adjudicated health plan claims data (07/2014 – 09/2016). Resource use and healthcare costs in the 6 months following treatment initiation were compared between non-matched populations, and between propensity score-matched groups, and by multivariable regression analyses.

Results

During follow-up, unadjusted all-cause hospitalization (6.6% vs 12.5%) and ED visits (17.0% vs 27.5%) were lower with brexpiprazole compared to quetiapine XR (both p<0.001). Brexpiprazole-treated patients had significantly lower mean medical costs (US$6,421 vs US$8,545, p=0.0123) but higher mean pharmacy costs (US$7,401 vs US$4,691, p<0.0001) than quetiapine XR-treated patients did. Total healthcare costs were not significantly different between the two cohorts. Propensity score-matched comparisons of 397 patients in each cohort showed no statistically significant difference in all-cause hospitalization, ED visits, and total healthcare costs; and significantly lower medical costs (US$5,719 vs US$8,602, p=0.0092) but higher pharmacy costs (US$7,091 vs US$5,091, p=0.0007) in brexpiprazole compared to quetiapine XR. In multivariable regressions, brexpiprazole was associated with 16.1% lower medical costs (p=0.0186) and 9.4% higher total healthcare costs (p=0.0463) as compared to quetiapine XR.

Conclusion

Significantly lower medical costs were observed in patients with MDD treated with brexpiprazole vs quetiapine XR.

Bioequivalence of two quetiapine extended release tablets in Chinese healthy volunteers under fasting and fed conditions and effects of food on pharmacokinetic profiles

Objective

The objectives of this study were to evaluate the bioequivalence of Quesero extended release (Quesero XR) tablets and Seroquel extended release (Seroquel XR) tablets under fasting and fed conditions and to determine the effect of food on the pharmacokinetic (PK) properties of Quesero XR or Seroquel XR in Chinese healthy volunteers.

Methods

A single-site, randomized, open-label, two-period crossover design with a 10-day washout period was conducted in 20 subjects under the fed and fasting studies. A single oral dose of 200 mg Quesero XR or Seroquel XR was given to the subjects after an overnight fast of 10 hours. Blood samples were taken at scheduled time spots from 0 hour pre dose to 36 hours post dose. Plasma concentrations of quetiapine were measured by a validated ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The PK parameters were calculated by non-compartment analysis using Phoenix WinNonlin software.

Results

On both conditions, no significant differences were found among the main PK parameters of the two preparations by analysis of variance (P>0.05); the Wilcoxon test of maximum peak plasma concentration (T_max) showed no significant differences (P>0.05); the 90% confidence limit (CL) of lnC_max, lnAUC_0→36, and lnAUC_0→∞ fell within the acceptable range of 80%–125%. As compared with the fasting state, the T_max was advanced and the mean maximum plasma concentration (C_max), AUC_0→36, and AUC_0→∞ were also increased in the fed state; the geometric mean ratio and 90% CI of the main PK parameters fell outside the range of the CIs; analysis of variance showed significant differences in the other PK parameters except for apparent total clearance after oral administration (clearance rate; P<0.05).

Conclusion

The two formulations of Quesero XR and Seroquel XR are bioequivalent under both fasting and fed conditions, and food may affect the PK profiles by increasing the rate and extent of absorption of Quesero XR or Seroquel XR in Chinese healthy volunteers.

Schizophrenia: synthetic strategies and recent advances in drug design

Schizophrenia is a complex and unpredictable mental disorder which affects several domains of cognition and behaviour. It is a heterogeneous illness characterised by positive, negative, and cognitive symptoms, often accompanied by signs of depression. In this tutorial review, we discuss recent progress in understanding the target sites and mechanisms of action of second-generation antipsychotic drugs. Progress in identifying and defining target sites has been accelerated recently by advances in neuroscience, and newly developed agents that regulate signalling by the main excitatory neurotransmitters in the brain are surveyed. Examples of novel molecules for the treatment of schizophrenia in preclinical and clinical development and their industrial sponsors are highlighted.

Efficacy and safety of quetiapine extended release monotherapy in bipolar depression: a multi-center, randomized, double-blind, placebo-controlled trial

RATIONALE

Quetiapine extended release (XR) has been used to treat various psychiatric disorders, including depressive episodes associated with bipolar I and II disorders. Quetiapine XR is the first approved drug in China for the treatment of bipolar disorder.

OBJECTIVES

The study evaluated the efficacy and safety of short-term quetiapine XR monotherapy in the treatment of depressive episodes of bipolar I and II disorders.

METHODS

This was an 8-week multi-center, randomized, double-blind, placebo-controlled, fixed-dose phase 3 study. The primary endpoint was the mean change of the Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Secondary endpoints included Clinical Global Impressions-Bipolar (CGI-BP) and remission rates.

RESULTS

The study recruited 279 adult bipolar I or II patients currently experiencing depression from 11 Chinese provinces. Of these, 139 received quetiapine XR (300 mg/day) and 140 received placebo for 8 weeks. The mean change in the MADRS total score was significantly greater in the quetiapine XR group than in the placebo group (-19.00 ± 7.88 vs. -16.20 ± 9.32; p = 0.004). Adverse events occurred in 96 patients (65.3 %) in the quetiapine XR group and 72 (49.0 %) in the placebo group. The incidence of serious adverse events did not differ significantly between the groups (p = 0.247).

CONCLUSIONS

This study, which is the first to evaluate 300 mg/day quetiapine XR monotherapy for depression in Chinese patients with bipolar disorders, found that this drug was superior to the placebo. Quetiapine XR was generally safe and well tolerated (ClinicalTrials.gov number, NCT01256177).

Drug-induced gastrointestinal disorders

Drug-induced gastrointestinal disorders can mimic conditions, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) and, hence, recognition can prevent unnecessary investigations and treatment. While the knowledge and awareness relating to the adverse gastrointestinal effects of some medications, such as non-steroidal anti-inflammatory drugs are well established, other commonly prescribed drugs, such as antipsychotics, antidepressants and metformin are less well understood and warrant further study. This review attempts to integrate recent information regarding adverse drug reactions and place this in a useful clinical context.

Comparison of the effects of quetiapine extended-release and quetiapine immediate-release on cognitive performance, sedation and patient satisfaction in patients with schizophrenia: a randomised, double-blind, crossover study (eXtRa)

OBJECTIVES

To assess daytime cognitive performance, sedation and treatment satisfaction in patients with schizophrenia receiving quetiapine extended release (XR) versus quetiapine immediate release (IR).

METHODS

Phase IV prospective, double-blind, crossover study (NCT01213836). Patients (N=66) with stable schizophrenia, treated with XR or IR before study start, were randomised (1:1) to treatment with XR followed by IR, or IR followed by XR, at the dose received before enrolment (400-750mg). After 10-16days on formulation 1, patients switched to formulation 2. Assessments from three post-dose visits (≥5days following treatment on each formulation) were analysed. Cognitive performance was measured by CogState Cognition testing. Sedation, treatment satisfaction and safety were also assessed.

RESULTS

65 patients received treatment (69.2% male; mean age 37.8years). Daytime cognitive functioning was similar for both groups; adjusted mean difference in Attentional Composite Score in XR and IR patients was 0.005 (p=0.907). Patients receiving XR were less sedated than those receiving IR, (Bond-Lader visual analogue scale score, mean [SD]: 23.5 [19.0] vs 28.6 [21.4]); estimated overall treatment difference: 5.2 (95% CI: 2.3, 8.2; p<0.0009). Patients receiving XR reported feeling less sedated than those on IR (Stanford Sleepiness Scale, mean [SD]: 2.4 [0.9] vs 2.6 [1.0]); estimated overall treatment difference: 0.28 (95% CI: 0.12, 0.43; p<0.0008). Patients reported improved overall treatment satisfaction (p=0.0417) and milder side effects (p=0.0035) with XR. Safety profile was similar in both groups.

CONCLUSION

Daytime cognitive performance was similar for both groups. XR was associated with less daytime sedation and improved patient satisfaction than IR.

The efficacy and safety of once-daily quetiapine extended release in patients with schizophrenia switched from other antipsychotics: an open-label study in Chinese population

BACKGROUND

Non-adherence to antipsychotic medication in schizophrenic patients is common and associated with symptom relapse and poorer long-term outcomes. The risk factors for treatment non-adherence include dosing frequency and complexity. Besides, slower dose titration in an acute schizophrenic episode may lead to attenuated efficacy. Therefore, the convenient dosage regimen and rapid initiation scheme of quetiapine extended release (XR) were expected to provide better effectiveness and promote adherence in patients with schizophrenia. This study was implemented to assess the efficacy and safety of once-daily quetiapine XR in schizophrenic patients with switched from other antipsychotics which were suboptimal due to insufficient efficacy or tolerability.

METHODS

This was a 12-week, open-label study conducted in the Chinese population in Taiwan. Patients who had a score of 4 (moderate) or greater on any of the 7 items of the Positive and Negative Syndrome Scale (PANSS) Positive Symptom Subscale and needed to switch from previous antipsychotics were recruited. Quetiapine XR was administered at 300 mg on day 1, 600 mg on day 2 and up to 800 mg after day 2. From day 8 until the end of the study, the dose of quetiapine XR was adjusted within 400-800 mg per day, depending on the clinical response and tolerance of the patients. The variable of the primary outcome was the change from baseline to Week 12 in PANSS total and subscale scores. Secondary outcome was the baseline-to-endpoint difference in the Clinical Global Impression-Severity (CGI-S) scores of the participants.

RESULTS

Sixty-one patients were recruited and 55.7% of them completed the study. The mean changes in the PANSS total score and CGI-S score showed significant improvement (-18.4, p < .001 and -1.0, p < .001, respectively). Four patients (6.7%) experienced adverse events including headache, exacerbation of psychosis and dysuria. The use of concomitant anticholinergics decreased from 15.0% to 8.3%.

CONCLUSIONS

The results of our investigation implicated that quetiapine XR was an effective and well tolerated alternative for Chinese schizophrenic patients with previous suboptimal treatment. Future large-scale studies are warranted to validate our results.

TRIAL REGISTRATION

ClinicalTrials.gov ID NCT02142556 . Registered 15 May 2014.

Drug-induced gastrointestinal disorders

Drug-induced gastrointestinal disorders can mimic conditions, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) and, hence, recognition can prevent unnecessary investigations and treatment. While the knowledge and awareness relating to the adverse gastrointestinal effects of some medications, such as non-steroidal anti-inflammatory drugs are well established, other commonly prescribed drugs, such as antipsychotics, antidepressants and metformin are less well understood and warrant further study. This review attempts to integrate recent information regarding adverse drug reactions and place this in a useful clinical context.

Active metabolites as antidepressant drugs: the role of norquetiapine in the mechanism of action of quetiapine in the treatment of mood disorders

Active metabolites of some antipsychotic drugs exhibit pharmacodynamic and pharmacokinetic properties that may be similar to or differ from the original compound and that can be translated by a different profile of responses and interactions to clinical level. Some of these antipsychotics' active metabolites might participate in mechanisms of antidepressant activity, as m-chlorophenylpiperazine (aripiprazole), 9-OH-risperidone and norquetiapine. Norquetiapine exhibits distinct pharmacological activity from quetiapine and plays a fundamental role in its antidepressant efficacy. In this review, we analyze the differential pharmacological aspects between quetiapine and norquetiapine, both from the pharmacokinetic and pharmacodynamic perspectives (affinity for dopaminergic, noradrenegic, and/or serotonergic receptors, etc.), as well as differential neuroprotective role. The pharmacological differences between the two drugs could explain the differential clinical effect, as well as some differences in tolerability profile and drug interactions. The available data are sufficient to arrive at the conclusion that antidepressant activity of quetiapine is mediated, at least in part, by the active metabolite norquetiapine, which selectively inhibits noradrenaline reuptake, is a partial 5-HT1A receptor agonist, and acts as an antagonist at presynaptic α2, 5-HT2C, and 5-HT7 receptors.

Impact of antipsychotics and anticholinergics on autonomic modulation in patients with schizophrenia

Antipsychotics are associated with cardiovascular risk, but the relationship between their anticholinergic properties and cardiac function is not clear. We hypothesize that antipsychotics with a high muscarinic affinity (HMA) may reduce parasympathetic modulation, which should be observable by means of heart rate variability (HRV) measurement. We also assume that anticholinergics, which are commonly used in patients with schizophrenia to treat drug-induced parkinsonism, interact with antipsychotics, and this may also affect HRV. Fifty-five patients with schizophrenia were recruited into this study. Twenty-eight subjects used antipsychotics with an HMA and 27 subjects used antipsychotics with a low muscarinic affinity (LMA). Heart rate variability values between the patients on antipsychotics with HMA and those on antipsychotics with LMA were compared. Correlation and regression analysis were then performed to clarify the relationship between HMA, LMA, and HRV. The influence of anticholinergics was also assessed by correlation analysis. The HMA group showed significantly reduced low-frequency (LF) power, high-frequency (HF) power, total power (TP), and normalized LF (LF%) than the LMA group. Regression analysis supported the hypothesis that muscarinic affinity was related to LF (β = -0.447; P < 0.001), HF (β = -0.390; P = 0.002), and TP (β = -0.399; P = 0.001). The interaction between LMA and anticholinergic use also influenced LF% (β = 0.326; P = 0.006). In the LMA group, the use of anticholinergics was positively correlated with LF% and LF/HF. In the HMA group, after exclusion of the patients using anticholinergics, the equivalent dose of antipsychotics showed a negative correlation with HF. Our results suggest that the muscarinic affinity of antipsychotics affects both sympathetic and parasympathetic modulation and that anticholinergics interact with antipsychotics to influence HRV.

Flexible dosing with paliperidone ER in the treatment of patients with acutely exacerbated schizophrenia: results from a single-arm, open-label study

OBJECTIVE

To extend findings from fixed-dose, double-blind, placebo-controlled clinical trials in selected patient populations by using flexibly-dosed oral paliperidone extended-release (ER) in a more naturalistic setting.

METHODS

Adults hospitalized with an acute exacerbation of schizophrenia were prospectively treated with open-label flexibly-dosed paliperidone ER 3-12 mg/day for 6 weeks.

RESULTS

Overall, 294 patients were treated. The primary endpoint, defined as ≥30% improvement in Positive and Negative Syndrome Scale total scores from baseline to endpoint, was achieved by 66.3% of patients. The percentage of patients rated as at least 'markedly ill' in Clinical Global Impression of Severity scale decreased from baseline (74.1%) to endpoint (20.0%). Patient functioning, assessed by the Personal and Social Performance scale, improved significantly from 50.0 ± 14.3 at baseline to 63.6 ± 14.9 at endpoint (p < 0.0001). Concomitant benzodiazepines were newly initiated in 191 patients (65.0%), and new concomitant medications other than benzodiazepines were started after baseline for 133 patients (45.2%), most frequently paracetamol, zolpidem, and zopiclone. No unexpected adverse events were identified.

CONCLUSIONS

These data support findings in more selected patient populations treated with fixed-dose paliperidone ER. Flexibly-dosed paliperidone ER administered in a naturalistic hospital setting to a more representative patient population experiencing an acute episode of schizophrenia, was associated with clinically meaningful treatment response. Strength of conclusions is limited by the open-label design and lack of a comparator group. Furthermore, some of the improvements observed may in part be associated with increased attention provided to patients and concomitant use of psychotropic medications, such as benzodiazepines, during this study.